CA1228144A - Radar velocity sensor - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A tracking, variable Q band pass filtering method and apparatus are provided for processing an IF
signal from a radar transceiver or the like. The method comprises developing a digital period signal corresponding to the period of each of selected cycles of the IF signal; subjecting the digital period signal to low pass filtering; and controlling the effective corner frequency of the low pass filtering in accordance with the amount of variation in the digital period signal from one selected cycle to a successive selected cycle for producing a filtered signal which substantially follows the digital period signal, thereby substantially simultaneously tracking and filtering the IF signal. The apparatus comprises apparatus for carrying out the foregoing method.
Preferably, the apparatus also includes an output switching control for selectively delivering or withholding the filtered signal from an output utilization device. This control is responsive to a predetermined control signal for withholding the filtered signal from the output utilization device. Preferably, the apparatus also includes a switchable power supply for the radar transceiver and a control circuit responsive to a predetermined control signal for switching the switchable power supply means to an inactive condition, thereby removing power from the radar transceiver.

Description

RADAR VELOCITY SENSOR

BACKGROUND OF THE INVENTION

The present invention is directed generally to the signal processing arts and more particularly to a novel and improved signal processing method and apparatus for use with a radar transceiver and associated circuitry for determining the velocity of a vehicle.

it The prior art has proposed a number of radar-based systems for determining the velocity of a vehicle.
Such systems are generally directed to the problem of monitoring the horizontal velocity of a vehicle traveling along a ground surface. Such radar speed monitors may be suitable for use from a fixed location in monitoring the speed of passing vehicles or alternatively, mounted upon the vehicle itself for monitoring of the speed thereof by an operator or driver of the vehicle.
The latter type of velocity monitor is particularly useful with respect to off-road vehicles, or farm implements, such as tractors or the like. In such vehicles, axle-mounted or other traditional velocity I

monitoring devices may become unreliable and/or inaccurate due to frequently encountered wheel slippage conditions in off road operation. Also, uneven ground conditions may add substantial vertical velocity components which tend to interfere with accurate speed measurement. Additionally, compaction of the wheels during operation, or changing of wheel sizes due to wear, or replacement thereof over a period of time will result in a change in the effective diameter of the wheel, whereby conventional wheel-shaft or drive-train based rotation responsive speed monitoring apparatus may prove inaccurate in operation. Radar based velocity monitoring apparatus has been heretofore proposed for overcoming these problems.

One such radar-based velocity monitoring system for a tractor is shown for example in Feather et at US.
Patent 3,895,384. While this monitoring apparatus has found widespread acceptance, there is room for further improvement.

In particular, such a radar system generally uses a radar frequency transceiver comprising a radar oscillator, an antenna, local oscillator and mixer to transmit and receive radar signals. The mixer operates to mix or multiply the received radar signal with the focal oscillator signal so as to provide at least one difference component signal in an intermediate frequency (IF) range, preferably in the kilohertz range, suitable for further processing by conventional electronic circuit components. In this ~Z2~

regard, the operation is analogous to that of conventional radio transmission involving a carrier wave similar to the transmitted radar signal and a signal component carried upon the carrier wave which is analogous generally to the Doppler shift or frequency variation in the received radar signal.
pence, only this difference is of interest in determining the corresponding horizontal velocity component of the vehicle.
As in all such radar Andre radio apparatus, various harmonic signal components spurious signals and/or noise signals in general can interfere with proper operation of the circuit and ultimately with the correct determination of the speed of the vehicle.
Accordingly, filtering is often utilized to limit the following processing circuits to substantially only the frequencies of interest, that is, the range of frequency variations expected in response to the expected range of vehicle velocities. In this regard, such off-road vehicles may be operated in a range of speeds from on the order of fractional miles per hour to on the order of tens of miles per hour.

Additionally, it is often desirable to shut off the radar antenna portion of the system when the vehicle is not in actual use in the field, or under other conditions. For example, when the vehicle is not in use, it may be considered desirable to minimize production of microwave radiation from the radar antenna. This may be true in the event of replacement, repair or repositioning of the antenna or other parts of the radar apparatus or of components of the vehicle which are located near the antenna.

Additionally, it is often desirable to cut off -the velocity monitoring function of such a system at relatively low vehicle speeds or when the vehicle is standing still. This avoids possible false response of the system to spurious horizontal velocity signals lo which may be generated when standing still, for example, by other moving objects within the range of the radar antenna. It will be understood that when the vehicle is in motion, the present invention is such that other such velocity components will be substantially rejected in arriving at the correct velocity indication. However, with the vehicle standing still, such relative movement in the field of the radar may under some circumstances be indistinguishable from movement of the vehicle.
Accordingly, it is desirable to a-t least prevent a velocity signal so generated from reaching the display components of the system, and moreover from reaching any further control apparatus which may operate a further implement in response to the velocity signal output of the monitor.

In order to substantially limit the response of the processing circuits to the signals of interest corresponding to the expected range of speeds, a band pass filtering circuit is generally utilized.
Moreover, in order to further limit the response of the system and reject a maximum amount of spurious, I

harmonic or noise signals, it is often the practice to operate this band pass filter in a band considerably narrower than the expected range of speed variations. This is facilitated by utilizing tracking control which varies the center frequency of the relatively narrow band pass to generally follow the frequency of interest in the incoming signal.
This further requires circuitry to accurately detect and identify this frequency of interest or fundamental frequency of the incoming signal.

additionally, some control over the bandwidth of the band pass filter is generally considered desirable in order to continue to accurately track changing incoming velocity signals, over a range of frequencies which may vary with changing velocity of the vehicle. That is, the bandwidth should be broad enough, when required, to follow relatively rapid vehicle acceleration or deceleration and the attendant relatively rapidly changing Doppler frequencies resulting therefrom. On the other hand, during periods of relatively stable or constant velocity operation, the bandwidth should preferably be kept relatively narrow to maximize spurious and noise signal rejection. However, conventional prior art analog band pass filtering, tracking and variable bandwidth or Q control circuits are relatively complex and expensive.

The prior art has proposed replacing such complex and expensive analog circuits with equivalent digital circuits, which perform essentially equivalent 8~4~

band pass filtering, tracking and Q control functions in a digital form, generally utilizing digital computer or processor components. Briefly, the computer model for a digital band pass filter including variable tracking and Q control involves selecting a sampling rate at least as great as the highest frequency expected to be encountered in the signal of interest. This computer implementation also involves the computation of a plurality of mathematical transformation functions which becomes relatively complex.

As a result, operating at a sufficiently high rate of speed to accurately sample and filter a sinusoidal signal of a frequency of on the order of even one or two kilohertz requires a surprisingly large amount of computing power. This is true because of the large number of computations which must be performed with respect to each sample and the relatively high sampling rate at which such samples must be processed in order to adequately follow the incoming signal.
Accordingly, relatively inexpensive single-chip microcomputer or microprocessor components which are generally available fall far short in terms of computing power of the requirements for such implementation of tracking band pass filtering.
Accordingly, it was heretofore believed that implementation of adequate band pass filtering including tracking and Q control in such a system would require relatively complex and expensive analog components, or alternatively, a digital computer system much too complex and expensive to be economically utilized in a typical off road vehicle - or farm tractor application.

OBJECTS OF THE INVENTION

Accordingly, it is a general object of the invention to provide a novel and improved radar-based velocity sensor for a vehicle.

A more particular object is to provide such a velocity sensor which utilizes a tracking and Q-controlled band pass filter, which may surprisingly be constructed from relatively simple and inexpensive electronic circuit eomponentsr thus avoiding the excessive expense of prior art circuits of this type.

A related object is to provide a signal processing circuit for a velocity monitor of the foregoing type which may readily be coupled with existing apparatus to accommodate display or other utilization of the monitored vehicle velocity information.

A further object is to provide a monitoring system which is capable of interrupting the power supply to the radar transceiver whenever desired.

A related object is to provide a velocity monitoring system of the foregoing type which is further capable of cutting off the velocity output signal to the display or other utilization apparatus whenever desired.

~228~

A related object is to provide a radar based velocity monitoring apparatus in accordance with the foregoing objects which is relatively simple and inexpensive in its design and manufacture and yet highly reliable in operation.
Thus, in accordance with a broad aspect of the invention, there is provided a tracking, variable Q band pass filter apparatus for processing an IF signal from a radar transceiver or the like and comprising: period counter means responsive to said IF
signal for developing a digital period signal corresponding to the period of each of selected cycles of said IF signal, and low pass filter means coupled for response to said digital period signal for producing a filtered signal which substantially follows said digital period signal thereby substantially simultaneously tracking and filtering said IF signal.
In accordance with another broad aspect of the invention -there is provided a Doppler radar apparatus mountable to a vehicle for determining the horizontal velocity thereof, and comprising radar transceiver means for transmitting and receiving respectively Doppler shifted radar signals, said radar transceiver means including a local oscillator for producing a local oscillator signal, and mixer means for mixing said received signals with said local oscillator signal to produce a predetermined IF signal; tracking band pass filter means responsive to said IF signal for producing a filtered signal I
-pa-corresponding substantially only to that portion of the received Doppler shifted signal corresponding to said horizontal velocity; sociably power supply means for said radar transceiver means and control circuit means responsive to a first predetermined control signal for switching said switcnable power supply means -to an inactive condition, thereby removing power from said radar transceiver means.
In accordance with another broad aspect of the invention, -there is provided a tracking, variable Q band pass filtering method for processing an IF signal from a radar transceiver or the like and comprising: developing a digital period signal corresponding to the period of each of selected cycles of said IF signal; subjecting said digital period signal to low pass filtering; con-trolling the effective corner frequency of said low pass filtering in accordance with the amount of variation in said digital period signal from one selected cycle 'LO
a successive selected cycle for producing a filtered signal which substantially follows said digital period signal, -thereby substantially simultaneously tracking and filtering said IF
signal.
BRIEF DESCRIPTION OF Tile DRAWINGS
The foregoing, as well as other objects, features and advantages of the invention will become more apparent upon consideration of the following detailed description of the -8b-illustrated embodiment, -together with the accompanying drawings, wherein:
FIGURE 1 is a block diagram of a radar-based velocity monitoring system utilizing signal processing components in accordance wit conventional theory;
FIGURE 2 is a block diagram of a second radar-based velocity monitoring system utilizing a second form of signal processing components in accordance with conventional theory;
FIGURE 3 is a block diagram of a radar-based velocity monitoring system constructed in accordance with the principles of the present invention;
FIGURE 4 is a block schematic diagram, partially in functional form, illustrating the operation of a radar-based velocity monitoring system in accordance I

with the invention; and FIG. 5 is a schematic circuit diagram illustrating a radar-based velocity monitoring system in accordance with the invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

The present invention is directed to a novel signal processing system for achieving a tracking, variable Q band pass filtering function, useful in many applications. The disclosed system is particularly useful in applications where a relatively limited and preferably primarily sinusoidal signal variation comprises the signal of interest to be followed.
That is, the system of the invention is particularly effective in providing an equivalent function to a tracking, variable Q band pass filter for non-complex signals in the kilocycle range. One such application is in tracking and filtering the Doppler shift frequencies of a Doppler radar transceiver. Hence, while the invention is not limited thereto, the following discussion will be directed to such a Doppler transceiver system.
Referring now to the drawings and initially to FIG.
l, a typical prior art radar velocity system includes a radar frequency (RF) front end 10. Generally speaking, such a "front end" includes suitable radar transceiver and antenna for both generating and receiving back radar signals The received radar signals will then be Doppler shifted in accordance with well-known theory, as compared with the originally transmitted radar signals.

To this end a further suitable local oscillator and mixer (not shown) also comprising a part of the RF
front end 10 are utilized to produce a suitable intermediate frequency IFFY for further processing by conventional circuit components. In this regard, the IF frequency produced by the local oscillator and mixer is preferably in the kilocycle range. Hence, an IF or Doppler amplifier 12 is provided for receiving this IF signal.

Further in accordance with prior art practice, a suitable tracking, variable Q band pass filter I may be provided for tracking and filtering the output of the IF amplifier 12. Here, various spurious signals, noise, harmonics or signals due to vertical velocity components or "bumps" may be eliminated from the signal of interest corresponding to horizontal velocity by proper filter design.

In this regard, it is desirable to provide a band pass filter which has a variable Q or bandwidth so as to reject signals outside of a relatively narrow band of frequencies expected from the IF amplifier in response to the expected range of vehicle velocities.
However, the Q or bandwidth of the filter must also be sufficiently broad to accommodate the maximum frequency changes or variations produced in response to maximum expected vehicle accelerations. In this regard, tracking and Q control circuits 16 are ~22~

provided for the filter 14. The resulting filter output signals from the filter 14 may then be fed by way of a suitable output circuit or buffer 18 as a signal Fox to a suitable display or other utilization device (not shown) as desired. As previously indicated, the realization of such tracking, variable Q band pass filters, and suitable tracking and Q
control components in analog form requires relatively complex and expensive circuits.
Referring to FIG. 2, the band pass filter and tracking and Q control may also be realized in digital form, utilizing suitable computer or processor components.
In this regard, the circuit of FIG.

2 includes a similar OF front end 10 and IF or Doppler amplifier 12. Departing from the circuit of FIG. 1, the filter 14 is replaced by an equivalent digital filter 22. Accordingly, a suitable sampler circuit 20 is interposed between the IF amplifier and the digital tracking variable Q band pass filter 22.
In accordance with conventional digital filter theory, the sampling rate or the sampler circuit 20 must be greater than the maximum frequency expected from the IF amplifier 12. That is, the rate of sampling of the sampler 20 must be sufficient to provide a reasonably accurate representation of all changes in this frequency 12, and hence must be sufficiently rapid to accommodate the maximum rate of change expected in response to maximum vehicle acceleration.

A suitable digital tracking and Q control circuitry 24 is similarly provided for the digital filter 22, . and is generally interposed intermediate the sampler 20 and an appropriate control input of the digital filter 22. Additionally, some suitable digital-to-analog or digital-to-frequency (D to F) output converting circuit 26 is also preferably interposed ahead of the conventional output buffer 18 for converting the digital output of the digital filter 22 to a frequency signal Fox suitable for use by the following display or other utilization circuits (not shown.

As previously mentioned, the computer model for a digital band pass filter including tracking and Q
control involves the computation of a plurality of mathematical transformation functions which become relatively complex. With the addition of a relatively high sampling rate at the sampler 20 and the requirement of correspondingly relatively rapid and frequent computations to accommodate both the band pass filter 22 and the tracking and Q control 24, the computing power requirements of such a computer model becomes surprisingly great In this regard, the requirements of computing power to achieve the digital filter circuits of FIG. 2 are considerably greater than that available on relatively inexpensive single-chip microcomputer or microprocessor components.

Referring now to FIG. 3, in accordance with the invention, it has been found that the equivalent functions of the relatively expensive circuitry of FIGS. 1 and 2, may be performed by an alternative arrangement of relatively simple and inexpensive digital circuit components in accordance with the principles of the invention.

In this regard, the radar system of FIG. 3 comprises a similar RF front end 10 and IF amplifier 12 to those already described with reference to FIGS. 1 and 2. Departing from convention, a period counter 30 is provided for producing a digital period signal corresponding to the period of at least selected cycles of the output signal of the IF amplifier 12.
The output digital period signal of this period counter is fed to a digital low pass filter 32 which has a variable corner frequency. The output of the period counter 30 is also fed to a suitable corner frequency control circuit I for selectively controllable varying the variable corner frequency of the digital low pass filter 32.
As will become more apparent upon reading the ensuing description, the foregoing circuitry comprising the period counter, digital variable corner frequency low pass filter 32 and the corner frequency control circuits I may surprisingly be realized in the form of relatively simple and inexpensive digital circuits and microcomputer or microprocessor components, contrary to the prior art systems illustrated and described above with reference to FIG. 1 and FIG. 2.
The resultant output of the digital low pass filter 32 is fed to a similar D to F converter circuit 26 and a suitable output buffer 18 for producing a 2Z~

suitable frequency signal Fox for driving a conventional display or other utilization apparatus (not shown).

Briefly, it has been found that for use with a limited range of IF frequencies, for example as expected in Doppler radar-velocity monitoring of off-road type vehicles, the system of FIG. 3 may be inexpensively realized in conventional single-chip microcomputer or microprocessor components without exceeding the limited computing power currently available in such components. In operation, it is believed that the period counter 30 operates upon the IF signal to essentially eliminate or convert the frequency components thereof to a series of relatively simpler discrete digital signals. Hence, filtering can proceed on a relatively simplified basis with attention only to variations between discrete digital signals, rather than the more demanding functions of following and digital reconstruction of a continuous frequency signal.
These variations will correspond to variations in the incoming IF signal about its nominal center frequency or fundamental frequency due to the vehicle velocity.

Moreover, in view of the relatively limited range of velocities as well as limited maximum acceleration expected with such an off-road or farm tractor type of vehicle, the sampling rate of the period counter 30 and of the digital low pass filter 32 need not be particularly great to accurately track or follow the ~22~

signals of interest.

Additionally, as will presently be seen, it has been found that a relatively simple and yet effective corner frequency control can be further simplified, so as to require the selection of only two or three different effective corner frequencies for the digital low pass filter 32. Hence, one relatively low corner frequency may be selected to effectively limit the effective filter bandwidth when the vehicle is being operated at a relatively steady or constant velocity. On the other hand, a relatively greater corner frequency may be selected for use when the vehicle velocity is changing due to vehicle acceleration or deceleration.

Moreover, it will be seen that the utilization of the period counter 30, digital low pass filter with variable corner frequency 32 and the corner frequency control 34 automatically achieve the tracking function of the band pass filtering components of the prior art in accordance with figures 1 and 2 as described above. This occurs due to the sampling of discrete digital period samples and to the selection of a suitable effective low pass corner in accordance with variations from sample to sample.

Stated another way, by comparison to conventional radio receiver apparatus, the period counter 30 functions in the manner of a mixer tuned to the IF
frequency. That is, the IF frequency component from the IF or Doppler amplifier 12 is thereby multiplied substantially by itself and hence canceled from the difference component. Accordingly, all that remains is the signal component of interest, that is, the Doppler shift or variation or frequency signals. As frequency signals, these can clearly have only positive values, thus existing only to one side of the nominal zero or IF frequency. Moreover, in view of the limited range of velocities of the vehicle being monitored, these Doppler shift variations are all within a relatively small range of frequencies above the now effectively "zero" IF frequency.
Accordingly, a low pass filter may now be utilized to effectively filter these remaining variation frequency components, which have essentially been converted from the frequency domain to the time domain by use of the period counter 30.

From the foregoing, it will now be appreciated that control of the corner frequency by circuit 34 together with the function of the period counter 30 effectively provides tracking of the IF signal and variations therein without the need for any separate tracking components or apparatus.

Referring now to FIG. 4, the operation of the system in accordance with the invention will be described in further detail. Reference is also invited to FIG. 5 which comprises a schematic circuit diagram of a preferred embodiment of a monitoring system which operates in accordance with the proceeding discussion and in accordance with the functional aspects of FIG.
4 to be next discussed.

As previously mentioned, a suitable radar frequency (RF) front end comprises a suitable antenna 40 for both transmitting and receiving the radar frequency signals. To this end a suitable oscillator 42 and mixer 44, for example in the form of Gun oscillator and mixer diodes are utilized. The incoming signals from the mixer are Ted to a suitable IF amplifying circuitry 12 which preferably includes a suitable preamplifier 46 having a gain factor Go, and second amplifier 48 having a gain Go and a final Doppler amplifier 50 having a gain factor Go.

In accordance with a preferred form of the invention, the amplifier 48 may be provided with a variable gain control input, illustrated in phantom line at 52.
Hence amplifier 48 is often referred hereinafter as a controlled gain amplifier. This variable gain control of amplifier 48 will be discussed later herein.

Further in accordance with a preferred form of the invention, the circuit 12 includes a DC restore circuit 54 interposed between respective amplifiers 48 and 50 which as will later be described, functions essentially as a high pass tracking filter.
Following the final Doppler amplifier 50 a suitable zero crossing detector 56 signals the period counter 30 at each zero crossing of the IF or Doppler amplified signal from amplifier 50 so as to produce a digital period signal corresponding to the period of this IF or Doppler signal. In this regard, a suitable high frequency clock, which in the illustrated embodiment provides a clock frequency of substantially 666.67 kilohertz is provided for the period counter 30.

In operation, the period counter functions to count the pulses from the clock 58 which occur between the zero crossings of the IF or Doppler frequency signal as detected by the zero crossing detector 56.
Accordingly, a period signal To is produced by the period counter 30 for substantially each cycle of the IF or Doppler signal.

Referring briefly to Fig. 5, the foregoing circuitry is indicated in circuit schematic form. In this regard, it will be noted that the DC restore circuit I comprises a pair of bipolar transistors 60, 62 of opposite polarity which are coupled in an essentially "back-to-back" configuration intermediate suitable DC
levels (plus 5, plus 12 and ground in the illustrated embodiment), and one input of an operational amplifier top amp) 62 which comprises the active component of the Doppler amplifier 50. The other input of this ox amp 62 receives the signal from the controlled gain amplifier 48. The transistors 60 and 62 will be seen to function essentially in the fashion of the back-to-back diodes illustrated and described in the previously mentioned US. patent to Feather and Beckman, No. 3,895,384. In this regard, this circuit configuration also effectively provides a tracking high pass filtering function, as it tends to limit the swing of the relatively low frequency variations of interest about the desired zero crossings thereof required for operation of the zero crossing detector 56. Such swings may occur due to high frequency components in the signal acting as a "carrier" for the low frequency components. Such high frequency signals might occur as "ringing" in response to rapid vertical velocity components, for example due to uneven ground surfaces, "bumps" or the like, or from other spurious or noise sources.

The remaining function of digital low pass variable corner frequency filter 32 and corner frequency control 34 are carried out in the present embodiment by a suitable microcomputer or microprocessor component 70. In accordance with the invention, it has been found that contrary to prior expectation, the required computing functions may be readily carried out by a relatively widely available and inexpensive single chip integrated circuit form of microprocessor 70. Accordingly, in the illustrated embodiment a microprocessor chip of the type generally designated 8049 is utilized.

Additional counting and clocking functions in conjunction with operation of microprocessor or processor 70 are carried out by a suitable integrated circuit multiple counter component 72. In the illustrated embodiment a counter component of the type generally designated 8Z53, which is a three-counter, processor-compatible integrated circuit chip, is utilized.

Referring now again to Fig. 4, the function of the -20~

processor and associated circuit components thus Ear described in achieving the novel digital filtering and tracking function in accordance with the present invention will next be discussed.

Initially, as a practical matter, some upper limit must be set upon the value of the output To of the -period counter 30. Accordingly, a maximum period (To Max) detector is coupled to a suitable overflow (OVA) output of the counter 30 for outputting a suitable maximum digital period count (To Max) in response to 'overflow" of the counter. It will be appreciated that a particularly low frequency input signal to the zero crossing detector 56 may result in such an 'overflow" and hence maximum period count and the resultant production of a To Max signal The To Andre To Max counter 74 signals are then functionally processed by an equivalent OR circuit 76. Additionally a minimum To value to define a maximum frequency input to the zero crossing detector 56 is detected at a functional block OWE In the illustrated embodiment, this block essentially provides a reset in the event the period count To is - 25 less than or equal to 256.

It should be recognized that the function of OR gate 76 and minimum period detect and reset clock 78 are carried out by the microprocessor 70. In the same fashion the microprocessor 70 and/or counting circuit 72 carry out the functions of the period counter 30 clock 58, To Max detector 74 and the remaining 2 2~L4~

functions of Fig. 4 to be described hereinafter.

The output of equivalent or block 76 is fed to a temporary storage register 80, which in turn feeds a working storage register 82. This working storage register 82 is in turn periodically sampled or clocked by a suitable sample clock 84 which in the illustrated embodiment is provided by one of the counting circuits of the integrated circuit 72 as lo indicated. In the illustrated embodiment, the frequency or rate of sampling of the sampling clock 84 is substantially 512 hertz.

Surprisingly, it has been found that this 512 hertz sampling rate is adequate to accurately follow or track the signals of interest in the illustrated embodiment. In this regard, the expected range of frequencies of the IF or Doppler signals produced in response to a typical off road vehicle or farm tractor are from on the order of 10 hertz to on the order of 2600 hertz. Below the lo hertz limit, the tractor or other vehicle is assumed to be essentially in a stationary condition, while such vehicles are generally not capable of speeds which would result in IF or Doppler frequencies above the 2600 hertz level, with the Doppler radar front end 10 utilized in the illustrated embodiment. In this regard, a suitable radar front end is more fully described, for example, in the above-referenced US. patent No. 3,895,384 and moreover, many suitable such radar devices are generally known in the art.

Moreover, since the acceleration capacity of such off road vehicles generally decreases with increasing velocity, the variations in IF signal to be followed due to acceleration of the vehicle will generally become smaller as the frequency of the signal increases with velocity. Additionally, since a discreet, digital period count signal is now being sampled by the clock 84, it has been found that the 512 hertz sampling rate is more than adequate to accurately reflect any changes in the value of this period count from cycle to cycle. This is true even though the sampling rate may in fact be shorter than the period counter cycling ravel or zero crossing rate at some higher frequencies.
The foregoing will be more fully appreciated upon considering operation of the digital filtering function to be next discussed. A digital low pass filter functional block is indicated generally at reference numeral 86. This digital low pass filter generally functions to calculate and store a sample value of the incoming digital signal in accordance with a given transfer function. This transfer function sets the sample value equal to the sum of a first proportion of the previously stored sample value and a second proportion of the incoming digital signal value. This relationship may be stated as follows:

v = mu yoke), where ,~? =: ( 1 -Go) From the foregoing, it will be seen that the effective "corner frequency" of such a digital low pass filter may be set by varying the foregoing "alpha" factor or proportion to change the "weighting" of the incoming digital signal in calculating the sample value. The output of the digital low pass filter 86 then comprises the digital sample values "y" computed in this fashion. Hence, it will be seen that tracking of the input signal is accomplished at a greater or lesser rate, depending upon the value of the alpha factor or proportion.
Moreover, the effective corner frequency, that is the ability of the filter 86 to "follow" variations in the incoming digital signal of more than a predetermined amount is also dependent upon this alpha factor or proportion. Accordingly, a suitable corner frequency or "alpha" factor selecting or control means is provided as indicated generally at functional block 88, which will be described next.
Surprisingly, it has been found that as few as two selectable effective corner frequencies or alpha factors for the digital low pass filter 86, are sufficient for adequate tracking and filtering in accordance with the present invention. However, we prefer to provide three such choices or selections of corner frequency or alpha factor. In order to select a given one of these corner frequencies or alpha factors at any given time, a set of reference filters functionally indicated at blocks 90, 92 and 94 are utilized. In the illustrated embodiment, reference filters 90, 92 and 94 comprise digital low pass I

filters. Additionally, the sampled period signals from working storage 82 is inverted or converted to frequency-like or frequency-related digital signals by a functional block 96D This inversion or conversion takes place prior to the feeding of a digital signal to the inputs of the respective digital low pass filter 86 and reference low pass filters 90, 92 and 94 which comprise the inputs to the corner frequency or alpha proportion or factor selection block 88.

This digital frequency-related signal (f) will be recognized to be a second digital value or signal provided at preselected periods in accordance with the sampling of the clock 84, which is also provided to suitable inputs of the reference low pass filters 90, 92 and 94. In operation, these reference low pass filters also comprise digital low pass filters as mentioned, and hence, also operate in accordance with the same transfer function given above. Hence, outputs of these filters comprise periodic sample values of the same form described above with reference to the digital low pass filter 86.
However, the alpha factors or effective corner frequencies of each of these reference low pass filters 90, 92 and 94 is preselected rather than variable.

In the illustrated embodiment, reference filter 90 is designated as the slow filter and has an effective corner frequency (Us) of on the order of .644 hertz.
Similarly, the reference filter 94 has been Lo designated as the fast filter and has a corner frequency (Of) of on the order of 2.59 hertz. The third reference filter 92 is designated as the "super fast" filter and has a corner frequency (Fsf) of on the order of 10.4 hertz. In this regard, the alpha factor of the slow reference filter 90 which corresponds to the effective corner frequency of .6~4 hertz is on the order of .0078. Similarly, the alpha factor associated with reference filter 94 is on the order of .03125r while the alpha factor selected for filter 92 is on the order of .125. These effective corner frequencies and alpha factors were empirically selected.

In operation, an additional selection of a "processing mode" may be provided by a selection block 96 which provides a suitable control input to the corner frequency selection block 88. This selection control is in the form of a two-bit signal Pi, Pi, and the notations inside corner frequency selection block 88 indicate the response thereof to the possible values of this two bit signal.

In this regard, with Pi, Pi selected as 0, 0, the control block 88 acts to compare the output of the slow reference filter 90 with the output of the fast reference filter 94. If the deviation between the values of these outputs is less than a given percentage (plus or minus H%) of the output of the fast reference filter 94 7 the selection or control block 88 selects the alpha factor .0078 of the slow reference filter as the alpha factor of the digital low pass filter 86. On the other hand, if the deviation between the outputs of the slow reference filter and of the fast reference filter 94 are greater than or equal to the same percentage (plus or minus H%), the control or selection block 88 selects the alpha factor .03125 of the fast reference filter I as the alpha factor for the digital low pass filter 86.

It will be appreciated with respect to the foregoing that with a relatively stable or slowly changing vehicle velocity, the sample values f at the output of block 96 will not be changing very rapidly.
Accordingly, all three reference filters 90, 92 and 94 will tend to follow these values f, without much variation between their sample value outputs. Hence, a relatively narrow or low corner frequency, corresponding to a relatively "slow" filter (such as filter 90) will be adequate to follow the digital signal f under these circumstances. Accordingly, the effective corner frequency or alpha factor for digital low pass filter 86 is so selected under these circumstances.

On the other hand, when the velocity of the vehicle is changing fairly rapidly, the successive values of the digital signal f will also change at a somewhat greater rate. Accordingly, in view of the foregoing sampling and transfer function of the three reference filters 90, 92 and 94 it will be appreciated that their outputs will begin to diverge or deviate as the variations in the successive samples f at their ~;22~

inputs begins to vary more greatly. Accordingly to more closely follow this now greater variation in the digital signal f, the digital low pass filter 86 must be a somewhat "faster" filter having a somewhat broader or higher corner frequency and hence larger alpha factor. Hence the selection of so-called "slow" and "fast" filter characteristics for digital low pass filter 86 is accomplished by the corner frequency control means provided by block 88 and reference filters 90, 92 and I

In accordance with a preferred form of the invention an additional "signal frequency window" functional block 98 is also provided. This block 98 functions essentially to eliminate or reject any signals f which vary by more than a predetermined amount from previous signals f. Briefly, such variations would be indicative of velocity changes, and therefore accelerations greater than possible with the off-road vehicle or farm tractor being monitored. Hence, such signals would be indicative of spurious signal generation, noise, or vertical velocity components due to uneven ground surfaces, bumps, "ringing" of the circuits or the like. Additionally, elimination of digital signals which vary by more than a predetermined amount from previous signals help to eliminate the effects of the phenomenum of "aliasing"
which is encountered in digital filtering theory.
Briefly, this phenomenum refers to the tendency of digital filters operating in accordance with the above noted transfer function to pass not only frequencies within their nominal or equivalent pass ~23~

band but also integral multiples or harmonics thereof. Hence, variations in the digital signal f which might result in any of the foregoing spurious or undesirable inputs to the digital low pass filter 86 are effectively eliminated by signal frequency window 98.

briefly, the signal frequency window 98 operates to reject any signal f and thereby deliver as input f' to the digital filter 86 those signals which vary by less than a predetermined amount from a center frequency value of based upon previous signals in the "train" of samples f. In this regard, a center frequency (of) for this determination is also selected by the control and selection block 88. As indicated in block 88, this center frequency (of) is selected as the output signal of one of the reference filters 90, 92 and 94 in accordance with generally the same criteria as discussed above for the selection of the alpha value for digital low pass filter 86. Accordingly, both of these selections or control functions are accomplished simultaneously in accordance with the results of the reference filtering described above. A suitable "halt" control line feeds an equivalent AND gate together with sample clock 84 to prevent operation of digital low pass filter 86 in response to any signal rejected by the window 98.

The output of the digital low pass filter 86 is designated as f'' and is fed through suitable output D to F conversion 26 comprising blocks 100, 102 and I

104 for conversion back to an equivalent frequency signal F0 suitable for use with existing display and other utilization circuits. As previously mentioned, the f'' signal may also be utilized to control the gain factor Go of amplifier 48 by way of control line 52. In this regard, if the resultant output signal f'' is less than a given percentage R of the minimum frequency (fin) of the system, which will be remembered to be on the order of 10.17 hertz, a first gain factor Go is selected for the amplifier 48. In the illustrated embodiment the percentage R is 737 and the gain factor Go selected when f'' is less than this percentage of fin is 8.8 volts per volt.
Otherwise, a gain -factor Go of 23 volts per volt is selected. At the same time, the output f0 is also preferably disabled by a block 108 if f'' is less than a second percentage P of fin. In the illustrated embodiment, P is selected as 147.

The 666.67 KHz, clock 58 feeds the last "frequency conversion" or output counter block 104. An additional output buffer 116 is inserted after this block 104 and receives a suitable control signal from block 108 by way of an OR function indicated at 114.
A suitable "power-up" delay or control circuit 112 also feeds into this OR functional block 114.

Other constants selected in the illustrated embodiment are as follows:
K' is selected as 2 , N is selected as .25, Go is selected as 40 volts per volt, Go is selected as 10 I

volts per volt.

Referring again to Fig. 5, additional circuitry is added in accordance with a preferred form of the invention to accommodate two further preferred features. As previously indicated, under some circumstances it is desirable to disable either the radar unit 10 itself or at least to disable the output thereof to prevent response thereto by a display or other utilization devices.

In the former regard, a suitable positive voltage supply of on the order of plus 5 volts DC is provided to the radar apparatus including oscillator 42 as indicated generally at reference numeral 120. This positive 5 volt supply is preferably provided by a power supply circuit designated generally by reference numeral 122 and including a 5 volt integrated circuit voltage regulator component which provides the positive 5 volts DC to input 120 at a corresponding output 126 thereof. This and a further similar 5 volt regulator 128 are coupled to a suitable power source such as a positive 12 volt vehicle battery by way of a switching circuit comprising a pair of switching transistors 130 and 132. A suitable "sense and inhibit" control input 134 is provided for receiving a suitable control input signal for controlling the switching of these transistors 130, 132 and thereby controlling powering up ox the regulators 124 and 128 from the 12 volt battery at input terminal 135. In the illustrated embodiment, it will be seen that a suitable zoner I

reference level is provided by a zoner diode 138 and the sense and inhibit input signal at 134 feeds the base electrode of switching transistor 132 which, like transistor 130, is a PUP transistor in the illustrated embodiment.

The appropriate "sense and inhibit" control signal for switching transistors 130 and 132 so as to effectively disable the power supply to the radar apparatus 10 may be provided in response to any selected condition, for example by sensing this condition through a suitable sensor and providing a suitable control signal. Such may be a function of the microprocessor 70 if desired, or of a further control circuit or even a second processor or the like associated with another piece of equipment, for example, some implement or machinery being pulled by the tractor.

As previously indicated, it is often desirable to effectively disable or turn off the radar components 10 when the vehicle is not in motion to generally prevent response thereof to spurious signals due to movement of objects within the range of the antenna 40. Additionally, it may be desirable to eliminate microwave radiations from the area about radar antenna 40 while various repairs or other activities are taking place in this area. Accordingly, a suitable simple go/no go axle rotation sensor might be utilized at the "sense and inhibit" input 134.
Additionally, the "f minimum" value discussed above, when detected by the processor 70, might be utilized for this function.

similarly, such minimum velocity determined by way of a simple axle rotation sensor or alternatively by the processor 70 may be utilized as a control signal at an "axle RPM in" input 140 to inhibit the velocity output signal frequency F0. In this regard, it is noted that this output signal is produced at an output terminal OUT 1 of a portion of counter 72 designated generally by reference numeral 104. This output is fed to a analog level control and conversion circuit 142. The axle RPM or other minimum velocity control signal at input 140 is fed through a suitable level conversion circuit 144 to a suitable control port (at pin 38) of the processor 70. Responsively the processor 70 in turn controls operation of the counter 72 to inhibit the output of portion 104 in response to the minimum velocity control at input terminal 140.
us previously mentioned, this avoids possible incorrect response of a display or other utilization circuitry to spurious signals which might be generated while the vehicle is essentially standing still. As mentioned, under normal operation, the Doppler radar signals representing horizontal velocity of the vehicle are readily separated from such spurious or noise signals. However, this is not always reliably accomplished when the vehicle is essentially standing still, as the only signals remaining to work upon may be such spurious or noise input signals.

I

Additional circuitry comprises a suitable power up delay or sequencing circuit 112 mentioned above for the microprocessor 70. This circuit is tied to the power supply circuits 122 to accomplish suitable memory protection and the like upon powering up and/or powering down of the circuits of Fig. 5.
Additionally, the gain control line 52 feeds a suitable inverting input of an operational amplifier comprising the amplifier 48 by way of suitable intervening circuitry.

In order to fully describe the specific embodiment of the invention, the following pages contain a reproduction of a suitable software or programming for the microprocessor 70 in accordance with the foregoing description.

While the invention has been illustrated and described herein with reference to a particular embodiment, the invention is not limited thereto.
Those skilled in the art may devise various changes, alternatives and modifications upon reading the foregoing description. The invention includes such changes, alternatives, and modifications insofar as they fall within the spirit and scope of the appended claims ASSUME flyer MACRQFILE
_ I 2B~
ISIS-II MC~-48/UPI-41 MACRO ASSEMBLER. V3.0 F -THIS FILE ON DISK (WRITHER STEVEN Stone LOO o'er LINE SOURCE STATEMENT
I TITLE THIS FILE ON DISK IR2010)-AUTHOR STEVEN STONE') 2 ;

3 ;

4 THIS FILE HAS Counters OF THE 8253 GETTING A NEW

5 MODE FORD IN ruse THEIR Own ONE JOT MESSED UP BY NOISE.
b ;
7 ;
it statewide US SCRSP.OOI 11-11-82 9 ;

If ;R2000 3--15-83 DOUBLE RECIPROCAL OF FILTER So 12 ;R~VOI 4-18-~ add STOP ROUTINE TO Help AGONY
13 ; false START UP'S
14 ;R2002 4--20-83 ADD POTION SENSOR INPlll 15 :R2003 4--21-83 MAKE CITRON I/- 12'~
16 ;R2004 4--21-83 MAKE CONTROL I/- 6X
17 ;R2005 5-13-83 USE LID INSTEAD OF HOLD FOR STARTUP
18 ;R200b 5--13-83 C15H2 LO CAIN >15HZ HIGH GAIN
19 ;R2007 5--20-83 RESET Moles ON 82~3 20 ; LYE Playboy FOR 8253 CHIP SELECT
21 ;R2008 6-1- 83 MAKE STARTUP Positive RANGE Burger22 ; HAKE GUNWALE C 75HZ GUNK
23 ;R2009 6- 23-~3 REWOVE LEVEL DETECT CODE
24 ; MAKE SUPE~FAST FILTER OLDEN
25 ;R2010 7-20-83 KIWI Output TO COURTERS RIGHT AFTER
oh ; 512HZ WAIT ROUTINE.
21 ;
2g SAMPLE RATE 51~HZ
29 ;
30 SCORNER Furnishes ~.~ U) FOR OUTPUT SLOW
31 ; (2.59) FOR OUTPUT FAST
32 ; (.332) FOR INPUT slur 33 ; 12.5~) FOR INPUT FAST
34 ;SUPRFAST FILTER (10.4) FOR INPUT AND GUlPUT
35 ;
36 ;
37 ;*~ *~*~*~ *I

39 ;~**~ *I
40 ;00 ROW UNDEDICATED EMORY POINTER USED ONLY IN MAIN
41 owe Al SAMPLE CCl~TER USED TO INlTlATE Control L WE ~32HZ) 42 ;02 R2 UNDEDICATED SCRATCH REGISTER USED ONLY IN CAIN
43 ;03 R3 n u 45 ;05 R5 u I I I "
47 ;07 R7 U
48 ;08 THRUM 17 SYSTEIl STACK DEEP

50 ;19 Al' TEMPORARY ACCUMULATOR PURRING INTERRUPT PROCESSING
51 ; lo R2' 52 RID R3' : 53 TIC R4' PERIOD count LOB TEMPORARY REG.
I RID R5' PERIOD COUNT MOB EMPEROR REG.

ISIS-II MCS-4S/UPI-41 MICRO ~SSE~IBLER. ~3.0 THIS FILE ON DISK IR2010)-AUTHOR STEVEN STONE
LOO OBJLINE SOURCE STATEMENT
55 VIE Rub PERIOD COUNT LOB HOLDING REG.
56 IF R7 PERIOD CHUM MOB HOLING PEG.
57 ;20 FIST REF. FILTER LOB 30 LOB OLD PERIOD
58 ;21 FIST REF. FILTER By I MOB OLD PERIOD
59 ;22 FAST REF. FILTER SUB 32 ho ;23 SLOW REF. FILTER LOB 33 61 ;24 SLICK REF. FILTER MD 34 $ OF PUS Sills CNTR
ho ;25 SLICK REF. Fuller By I # OF TOTAL SUMS CNTR
63 ;26 OUTPUT FILTER LOB 3b LOB OUTPUT Fluter FOR SCALING
by ;27 Output Filler MY 37 MY OUTPUT FILTER FOR SCALING
65 US OUTPUT FILTER SUB US MOB Output FILTER FUR SKYLINE
6b ;29 RECIPE PERIQB CUT. LOB 3q 67 I RECIPE PRY curt. MS PA
68 ;2B RECIPE PERIOD CUT. MOB 3B
69 ;2C 3C NEW PERIOD FLUKY
70 ED ED STY W FLAG (I $ TQPPEDI

72 OF OF LAST Slate FOX

I I **I *~*~
7b FLAGS
77 Jo ***~*~*~ *~**~
78 FOE WTPUT FILTER SELECT (FOCI INDICATES FAST FILTER SELECTED) 7q FOE USED TO INITIATE OVERFLOW SWEENEY IN INTERRUPT
**I ~*~ *I
81 ;1/0 MAP
I lo *I
83 TINT/ SAMPLE RATE CLUCK INPUT (NOT USE US INTERRUPT) 84 TAO RADAR SOGGILY INPUT TO lNTERN~L COUNTER TO PRESET TO (OFF) SO TO
85; IJENRA~E AN INTERRUPT EARN RISING ERIE
8b TO PERIOD COUNTER OVERFLOW FL (TORI INDlCATtS OVERFLOW) 87 flus DATE BUS TO 8253 TIMER WUNTEF. CHIP

89 POW R R n it i R r 90 SPORT 1 BIT Bit FUNCTION
91; O O COMBINATION
92; 1 0 REF. FAST
93; 0 1 REF. SLY
q4 ;P12 I OF 4 OUTPUT SCALE FACTORS Dwight 95 ; p 13 n u n Y
96 ;P14 WINDOW REJECT SELECT (ISSUE/. 0-+25X) 97 ;P15 ~JINDOil REJECT SELECT IS OX 0=-;25X) 98 ;P16 CHIP SELECT FOR 8253 99 ;P17 256HZ fOliGLE FOR ITCH Luke 100 ;~*~*~**~*~**~*~*~ *
101 ;P20 END P21 DORIS SELECT FOR 8253 TIMER CENTER CHIP
102; P20 P21 103: 0 0 COUNTER O

105; 1 0 Counter 2 106 ; I I CONTROL
107 ;P22 RESET LEVEL DETECTOR
108 ;P23 SIGNAL OUTPUT DISABLE (OUTPUT Ho then DISABLED) 109 ;P24 LOW LEVEL DETECT IPIPUT (I= OX O-BAD) ISIS-II Mcs-4slupl-4l MACRO ASSEMBLER, V3.0 THIS FILE ON DISK (WRITHER STEVEN STONE
LOO orology LINE Solace STATEMENT
Pus CAIN CONTROL OUTPUT
111 ;P26 HIGH LEVEL reticula INPUT ll=GOOD OBEYED) 112 ;P27 MOTION solacer INPUT landlady AND HICIH=DlSABLED
I to ~15; --fib; GO TO INITIALIZE RolrTlNE
117;
OX o 0000 040~ 119 ZIP INITRL
120;
1; GO TO Timer INTERRUPT SERVICE RouTlNr In ;
0007 123 Fig 7 0007 self 124 JUMP PERIOD
:
l26; THIS THE INITIALIZE WRITENOW WHICH DlsAr~LEs SIGNAL OuTpllT~
127; SET PUTS TO sTMrlNG LEVEL CLERK ROLL REGISTERS AND Flywheels ; AND INITIALIZES THE S253 cl!uNTr-R CHIP.
;
130; SET UP PORT 2 FOR Output SET DEFAULT LEVELS
131;
zoos D4sB l32 INllAL: CULL COON
o'er 23F7 133 MOW A7~F7H clitoral REG.-ON ~53 ADDRESSED
OKAYED PA 134 OllTL FOE Walt 3 LO DISABLES S253 OUTPUT
;
l36; SETUP PUNTER O FOR ODE O OUTPUT HIGH ON TERMINAL CUT
137; THIS colJNrER USED FOR SAMPLE RAZE lNpur CLOCK
lug;
OBOE 2330 13~ MOW AYE
Oslo Jo 140 VEX ROY
141;
142; SETUP COUNTER I FOR MODE 3 squire DAVE GENERATOR
143; THIS COUNTER USED FOR OUTPUT SIGNAL
14q;
Toll 2376 145 110V AYE

;
143; SETUP COUNTER 3 FOR MODE O OUTPUT HIGH ON TERMINAL COUNT) ; THIS COUNTER us TO Syria PERIOD QUINT ROD SIGNAL
150; OVERFLOW cr~DllloN owl TO INPUT).
151;
0014 23~Q lo MOW ABACK
0016 go 153 MOVE ROY
1517;
155; SET up Coupler O FOR sluice OUTPUT HIGH ON TERMINAL CENT
lob;
0017 safe 15Z AWL Pi, tOFCH;ADI)RESS CUTER O
0019 eye 158 110V AHAB PRY LOAD DO COUNTER WITH 125q ~OlEBH) OBOE Jo 155' MECCA ROY TO F~VIUE A SAMPLE RATE CLOCK OF sluice OKAY 2304 160 ova 04H
OOZE JO Ill MOVE ROY
162;
163; RELOAD Kilter 2 Al rho offset I INTERRUPT SERVICE DELAY TIME
;

I

ISIS-II MCS-48/UPI-~1 MYRA ASSEM~LER1 V3.0 Thus FILE ON DISK IR2010)-AUTHOR STERN STONE
LOO OBJ LINE SIRIUS SlATEPlENT
OFF AYE 165 OWL P2.~02 ADDRESS COUNTER 2 0021 2301 I MOW AYE PROOF LOWE Dun ColJNTER WITH 1 0023 90 Ih7 MOVE QRO.A SO IT WILL tlVERFLOW ON POWER UP

0025 90 169 OX pro 171;
172; SETUP INTERNAL TIME AS LATCHED EXlERl`lAL INTERRUPT
173; THIS Interrupt IS USED SIGNAL THE EON OF A PERIOD
174;
0028 23FF 175 MOW A.#OF~H
002r 62 176 MOW TEA SET W INTERNAL UP COUNTER TO OVERFLOW ON lye 177 IT Falling EDGE OF rye WRIER SIGNAL WHICH INTERN
1/8 generals AN INltRRWT INDICATING A STAT OF r 180;
1~^1; NOW CLEAR ALL REGISTERS Ann FLAGS
182;
002B 85 18~ a FOX awry REGISTERS lorry AND FLAGS
002C A 184 a Fly 002F 1~000 186 BKUPI: MOW ROY
0031 E82F 187 DJNZ RO.BKUPI
188;
189; SET FILTER VALUES TO ~EFAULI values 190; THE VALUES ARE FOR THE SLOWEST ' OUTPUT FREQUENCIES
lgl;
0083 B81C 192 OVA Relish (\035 OF i93 110V A,~OFFH

00'~ 18 195 IN ROW
0039 A 196 ilOV ROY

003C 18 i5/^J IN ROW

00~ I 201 MQV ROY
0040 ~01 ~02 TV AYE

0043 B~25 204 Levi ROY
0045 A 205 MOW Rowley 004$~ B328 206 IVY ROY

208;
209; SET STOPPED FLAG
210;

004~ BOO 212 TV Rowley 213;
214; SET Us PORT I FOR Input 215;
004D OF 216 MOW A,#OFFH
Oq4F 39 217 QUIETLY Plea 218;
219; Al IS USED AS A DOWN Coupler WHICH Al 0 Connors INITIATES

ISIS-II McCauley Mr7CRO ASSEMBLER V3.0 They'll FILE ON DISK (R2010)-AUTHdR STEVEN STONE
LOO OX LINE SOURCE SrATE~ENT
220 ; THE CONTROL ALGORITHM.
~21;
Ode Elude 222 MOW Rl.7~10H
22? ;
224 ; ENABLE TIMER INTERRUPTS BUT Leave EXTENUATE. DISABLED
:2~5: ,, 0052 25 22b EN SHUT
Ode 45 227 STRUT CUT
22~;
22~;7~*~***~*~7~#**~#~**~*#~#*~***~#7~#~*~*~**~*~*#*~~#**~*~**~#**~****#~#
230 ;
~31 ; THIS IS THE MAIN LOOP STARTING Point.
~32 ;
233;#~*~*#~#~*#~.#~#*~#~* ~*#~*#~*~*~7~*~7~*~#7~#**##~#~#~*~#
234 ;
Ode B460 235 MAIN: CALL SCALE SCALE and RECIPE Outfit FLIER
005b 8656 ` 23b MANIC NOAH MINI WAIT FOR EXTENUATE. TO GO HIGH
237 ;
238 ; NO CUT READY TO OUlPllT NEW PERIOD INFO
SUE :
0058 35 24d Owlet: DISK TCNTI
0059 Do 241 SOL RIB
242 ;
24~ ; PUT PERIOD INFO IN OLD REG. BEFORE REPLACING IT
24~ ;
AYE ~30 245 Rd,~30H
005C FE 2~b MOW Aruba doze 18 248 IN ROW
doss OF 24S' MOW AWRY
Hobo A 250 MOW QRO,A
251 ;
~52 ;
OObl FC 253 OVA AWRY
Oboe AH 254 OW Bra Odb3 FED 255 OVA AWRY
ddb4 A 25b MY ROY
Oboe C5 257 SOL REDO
258 ;
25q ; NO heck FOX RESET Made FOR CNTR I
26Q ;
Cobb 9aFC blue COUNT: AWL P2,#0FCH
Oboe Boyle 2b2 OWL F2,~1 Oboe FE 2b3 MY ~,R6 906B D48S 2b4 Call Showdown Dodd 90 2b5 OX ROY
Ooze OF ebb MOW AIR/
OObF 90 2b7 OX ROY
0010 D471 268 Call SEPTIC
Ode EYE 2b9 CALL CHECKOFF

Dow Ox 271 NO
0~76 Ib7A 272 JTF CLIP
~18 047C 273 JUMP FILTER
AYE 941F 274 CLAP: CULL PERIOD

ISIS-II MCS-48/UPI-41 MICRO Assembler. V3.0 THIS FILE ON FISK (Roarer STEVEN STONE
LQC OPT LINE SOURCE STATEMENT
275 ;
276 ;*~**~***~ *I ***~*~*****~**~*****~***~**~**~**~**~*~**~***~*~*~~
'27'~ ;
278 ; THIS IS TOE Fist REFERENT Of FILTER
27~ ;
280 ;~*~*~***~**~*~*~*~
281 ;
007C 09 282 Filler: IN Apple FLIP Ply FOR WATCH DOG CIRCA

00~/~ 437F 284 QRL A,$7FH
ox I ~85 our Plea 286 ;
287 ; SOT STACK FAINTER Buck TO NERO HERE INCISE OF NOISE-~8 ;
00~2 C7 2~9 MY APSE
0083 ~F8 290 AWL A,~OF~H
~0~5 Do 291 M W SUE
I ;
293 ; CHECK FOR PERIOD OVERFLOW
2q4 ;
00 268F 295 UNTO Grouter 29b ;
297 ; IF PERlQD OVERFLOW THEN PERIOD = FFFF
2~8 ;
00~8 23FF 299 MOW A,#OFFH
AYE BYWAY 300 M W Rowley 00~ A 301 MOW OWE
008rl 18 302 IN M
PUB A 303 MY Roy 304 ;
305 ; NOW Gel RECIPROCAL OF THE PERIOD courier Data 306 ;
008F 9473 307 GET: CALL REEQUIP GET RECIPROCAL Of Person jog;
309 ;
0091 l8r~CJ 310 MOW ROY SAVE IN Cobb O'er FED 311 MOW AWRY
0094 A 31~ M W ROY

00% FE 314 us Aruba 0~97 A 315 MY ROY
00~8 18 316 IN ROW

OWE A 318 MY Moe 319;
320; NOAH CHECK FOR SUPER FAST FILTER
321;
00~ 09 322 IN APE
~qC .~v3 323 AWL A.
EYE 03FD 324 ADD Aye OWE Eye 326 JUMP SUPER lo TO SUPER FAST FILTER
327;
328; N014 VAST FILTER
3r~9;

o I
ISIS-II MC~-48/UPI-41 MACRO ASSEMBLER, ~3.0 this FILE ON DISK (R2dlO)-QUTHOR STE~t1N STONE
LOO OLD LINE SOURCE STAlEMrNT
Owe ~22 330 FROST: MY ROY JUNIOR (PROVE FIT FLUTTER OUTPOURED CNT/32 Owe An 33~ MOW R6.h Ode FOX 334 MOW hero Ode ho 335 OVA R51h Oboe C8 33b DEW ROW
OKAY FOX 337 MdV AWRY
338 ;
339 ; INN GETTING FAST FILTER INFO-NOW SHIFT RIGHT
340 ; 5 TIMES no GET (FIT FLUTTER) 341 ;
ODE ~8d5 342 MdV ROY

OdBO 47 344 SWOOP A
OBOE AC 345 OVA ROY ;LS~116 00~2 FED 34b MY AWRY
~QB3 18 347 IN ROW
OOB'l 30 343 XCHD AWRY

Cobb AD 350 MOW ROY ;~8/lb OBOE YE 352 XCH awry 35b ;
357 ; NOW ROTATE i TIME RIGHT
358 ;
OOBC FE 359 MOW Rub OBEYED 67 byway ARC R

OdBF AH 362 n W Roy FOCI by 364 ARC A
f~GC2 37 3~5 CAL A
OKAY ROD ~66 MOW ROY
OKAY FC 3b7 UOV AWRY

OOCb 37 369 CAL A
370 ;
371 ; NOW ADD FSI FLYER COMPLEMENTED TO FIT FLUTTER
372 ;
OKAY B820 373 SKIP: MOW ROY ADD 3 MOST SDNIF ROTA 0 BYTES TO PREY FIT FLUTTER own OKAY 70 377 ADD ho OKAY YE 376 OH Aruba 00 Of 18 379 ICKY ROW
OOCF 70 380 ~DDC AWRY
ODE A ~81 OVA Roy 382 ;
3$3 ; NO GUT 1/32 OF NEW Ann ADD TO 31/32 own 384 ;

LIZ
ISIS-II MCS-48/UPI-41 MACRO ASSUMER V3.0 THIS FILE ON FISK roarer STEVEN STONE
LOO Oral LINE SOURCE STATEMENT
ODE ~32D By MOW RUDY PURRED SHIFT RlGHr 5 TIMES

ODE AC 3~7 MOW ROY

OODb FOX 389 MOW AWRY

O'er FOX 392 MOW AWRY

394 ;
395 ; NO SHIFT RIGHT 4 TIMES
39~ ;

w DUD 41 398 SWAP A
CODE AA 399 MOW ROY ;LSB/16 00~3 A 404 MOW ROY ;MB/i6 OWE or 406 XCH AWRY

409 ;
410 ; NO ROTATE I TIME RIGHT
41~ ;

OWE FC 413 OW ~.R4 OWE 67 414 M C h OBOE AC 415 Mow R4.

fly ~æ20 421 SKIP: OVA RYAN ADD 3 ROTATED BYTES TO PREVIOUS 3 BYTE SUM

OFF 2400 424 JUMP Panel 4~5 ;
426 ;
0100 427 OR loo 428 ;
I ;
0100 18 430 Panel: ICKY ROW

0102 YE 432 ADD Awry 0103 I 433 MOW QRO.A

0105 FC 43~ MOW AWRY
910b OF 436 ADD AWRY
0107 ho 437 COVE QRO.A
4~3 ;
439 ; CF~K FOR OVER FLOW. IF CARRY SET MAKE FILTER FFFFFF

ISIS-II HC'S-48/UPI-41 MYRA ASSEMBLER. V3.0 -42-THIS FILE ON DISK lR2010)-AUTHOR STEVEN STONE
LOO I LINESOllRCE S'rAl`EMEPIT
440;
01~ EKE 441 JNC SLOFLT

I
/144; NOW DO SLOW filter FOR CONTROL
445;
OKAY B325 44b SLOFLT: MOW ROY general (PROVE SO FLUTTER OllT/25b)tPERIO~ CNl/25b OBOE FOX 447 MCiV AWRY
Olaf' 37 448 CAL A
OHIO A 449 MOW R5.

0l12 FOX 451 Levi AWRY
Olin C8 452 BECK ROW

OILS 60 454 ADD Awry ROD 2 MOST SGIIIF WRIGHT) BYTES TO PREY SO FLY OUT
Ollb ED 455 XCH AWRY ;EFI:ECTlVaY l~lERATlNC PRY FLY OUT/25b 0117 It 45b lNC ROW

OBOE FOX 460 MOW Awry OllC 13FF blue ABDC A,#OFFH
OWE A 4b2 OVA ROY
4b3;
~64; NOW GET NOAH
4b5;
OFF B82B ebb HO ROY To FREQUENCY COUNT
0121 FOX ~67 TV AYE
0122 AA 46~3 MOW ROY

0124 FOX 470 Tao AWRY
0125 B823 OX ROY Rudy Laredo TO PREVIOUS 3 ~YTf sir 0127 ED 472 Alleged AWRY

012g FAX 474 PEEVE AWRY
AYE YE 475 ADD Aruba 012B 18 476 It`tC ROW

EYE 1300 479 ADD Aye 0131 A 481 no ROY
482;
48;~; NOW CHECK FOR OVERFLOW. IF CARRY SET MAKE FILTER FFFfFF
~84;
0132 Eye 485 JNC CNTRL

487 ;~**~*~*~*~ ~***~*~.~*** lo 48i3 489; THIS IS THE Control PORCH OF THE PROGRAM
4S~0;
491; Control SWITCIIES In FAST inlay PHASE FILTER
492; IS IRE THAN I/- by AWAY FROM SLOW. fluter 4~3;
494; I *~**~ I to **-so lo ISIS-II MCS-48/UPI-41 MACRO AS8EM9LER, V3.0 I' Thus FILE ON DISK Ir~O10~-AJTHbR STEVEN STONE
LOO Orgy LINE SOURCE STATEML~T
4q5 ;
0136 EKE 496 CURL r~NZ Rl7WIN90~ SQUIRE CONTROL hLGQRlTHM 15 OUT by It SOMALI TIMES
0188 B~10 497 MOW Rl.#lOH RUSS Shirley C WINTER
498 ;
499 ; NO DO M~71'ROL hLGORII~
500 ;
AYE 9825 501 MY ROY IF (.9375 SO } FIT 1.0625 SLOW THEN FAST
013C go 5~2 CUR C SHIFT RIGHT SO FLUTTER 3 BYTES I BIT RIGHT
013D FOX 503 MOW AWRY TO Gel LOWE

Old AC 505 MOW R4.h 0140 C,`3 50b DEW ROW

0144 C8 510 wreck ROW

014b 67 512 ARC

0148 97 51~ CUR C SHIFT RlGHr ANN TO GET Slot 014C FOB 518 M W Aye 014Q by 519 ARC A
EYE A 520 OVA R37~

0150 67 522 ARC h 0154 67 52b ARC A

0157 67 52g ARC A

0159 FAX 531 MOW awry AYE by 532 ARC

015C I 534 Clue C ;SHlFr RIGHT Again TO Get SLY

EYE by 536 ARC A

0161 67 53~ ARC A
9162 A Tao OVA R37 0166 Eye 544 MY RUDY RESULT TO SO Flyer 10 Gel 1.0625 SO

Olb9 PA 54b ADD AWRY

OlbC FOX 549 MOW AWRY

ISIS-II MCS-48/UPI-41 MACRO ASSEMBLER- V3.0 THIS FILE ON DISK WRITHER STEVEN STONE

0160 78 55Q hDDC h.R3 0173 EYE S56 J~lC AWOKE JUMP IF No ~VERFL0 0175 23FF 557 MOW A7~0FFH

AYE Byway ~61 BASK: MOW R01~20H;SUBTRhCT FIT FLUTTER TO KIWI 1.0b~5 SLY - FIT
017C F0 5b2 MOW AWRY

Olaf 18 565 IN R0 0IB0 F0 ebb MOW AWRY
OOZE 37 5~7 CAL A

0Ig3 18 565' IN R0 018b OF 572 ADD AWRY
0IB7 85 573 a R F0 0188 95 574 CAL F0 SET F0=1 To SELECT FAST OUTPUT FILTER
01~9 EBB 575 JNC MARK IF FAST OUTPUT IS REQUIRED Go To OUTPUT FILTER

018B FAX 577 MOW AWRY ;C~MF~EM~NT SLY

0190 A 5~2 MOW ROY

01~2 37 5~4 CAL A

0154 E32f~ 586 M0V R0,~2~H ADD RESULTS To SLY FLUTTER To GET .9375 SLY

0198 37 589 CAL A THEN C0HPLE~ENT

AYE 18 ~91 IN R0 019C 7B S93 ADD Aye idea 37 594 CAL A

015~ 18 55'6 IN R0 AYE 7C 59~ ADD AWRY
AYE 37 5~9 CAL A
01h3 AC 600 Levi ROY
OWE B820 601 MOW R0.#20H;SUBTRAC~ FROM FIT FLUTTER TO Gel FIT - .5'375 SLY
AYE FOX ~02 HO AWRY

I
I
ISIS-II MCS-48/lPI-41 ~lhCRtl ASSE11BLER, V3.0 TESS FILE ON IJ18K (WRITHER Seven S101~ 1 LOO Owl LINE SOUSE STATEMENT
Olaf FOX 605 MOW AWRY
OIL Ed 606 ADD AWRY

ol~r~-/c TV ADrJC q OWE EBB 610 JNC MARK IF FAST Quietly IS REQUlREQ M TO OlllPUT Flyer OlBO 85 611 Of R FOX ELSE Stat FOE TO SELECT SO-. Output Flowerier 612;
613: NOW SCHICK FOR EXTERNAL FILTER SELECT
blue .
Old 09 615 IRK: IN hi OBOE 5303 616 AWL Aye Old CODA 617 JO MCKEE

011~ B83F 621 1~AltK2: MOW ROUGH
OIBC 2301 622 MOW to JIBE Equal 623 JO CKShME

OOZE DO 625 CKShME: XRL Art 011;2 C6C4 626 JO elf UP IF Some 627;
628; TOGGLE PORT FOR FhSl SLY SWITCH
629;
OKAY 2301 630 SETFO: Levi AWOKE
OlC6 B~C9 631 JO so Al OKAY 2-/ 632 Clue A
ICKY A 633 SET: OVA ROY
634;
635; NOW DO WINDOW RouTlNE~t Wit - 25/.) ~36;
PICA ~21 637 WINDOW: MOW 21H ROUGH. FAST FILTER
OIIX BbDO 633 JO SITUP
ONCE 23'24 639 MOW A.. #24H ROY'. SLICK FILTER
ODE A 640 SITUP: MOW ROTA
641;
642; NO RUT APPROPftlATL Filler IN R3-4 AN R~6 643;
ODE FOX 644 TV A.. PRO
OILY By 645 ItOV ROY

0111'5 FOX 648 MY AWRY
OKAY AC 64q YE R4.~
ODE A 650 11tlV ROY
~'51;
652; NQ~J DO 25X I~INOO~J

6~3;
01Ii8 9'7 65~ CUR C
ODE FC ~55 It h.R4 ' OIDC FOB 658 MQV AWRY

ISIS-II NCS-48/UPI-41 IIACRO assembler. V3.0 THIS FILE ON 111~ IR~O10)-AUTHOR STEVE STONE
LQC OBJ LINE SOURCE STATEMENT
OXIDE By byway MQV ROY
Olaf 97 661 PLUS: CUR C

Opel by 663 ARC A
OWE AC b64 MOW ROY
Oily FOB 6b5 IVY AWRY
OWE 67 bob ARC A
b67;
by NOW ADD 25X lo SELECTEE Fluter ANN CUMPLFMENT RESULT
669;

OlEb 37 671 CAL A
Oily Aye b72 MOW ROY
Oily FC 673 MQV AWRY
OWE OF b74 ADD AWRY
OWE 37 $75 CAL A
OBOE AC 67b MOW ROY
OKAY Fbf9 b77 JO CLUE IT IF OVERFLOW
678;
679; NOW Tut (kelp. - selected FILTER + 25%)) b80;
OWE Bra b81 MOW ROY
OFF FOB 6~2 MY AWRY
Olfl 60 683 AD AQUARIA
OlF2 18 684 lNC ROW
OFF FC 6~35 IIW AWRY
Olf4 70 68b ADD try OFF E6f9 b87 JNC CKLO~J JUMP IF thou OFF 4423 I JUMP REJECT Pi IF BAD
bS9;
b90; NOW CHECK FOR RECIPE Lower loan WINWIJ
b91;
6q~; NOW PUT SELECTEE FILTER IN R3-4 6~3:
OFF 4400 b94 SUCKLE: UP Puff 695:
69b;
0200 697 OR Thea 69~;
699;
0200 FE 700 POW: MOW AWRY
0201 A 701 MOW R3.
020~ OF 702 MOW AWRY
0203 AC 703 It R4.
704;
70~ -25X
70b;

' AYE A 713 TV ROY
020B 97 714 MOONEY: CUR C

I -ISIS SHOP Mutt A~SEMf3LER, V3.0 THIS FILE ON DISK (R2010)-~UTR~IR STEVEN Stone LOO OBOE LINE SWISS Statement 020F I 71~ MY ROY

021~ 67 720 ARC A
02~2 37 721 CAL
722 ;
723 ; OX ADD -I TO SELECTED FlLTf'R ANfJ COUP RESULT
124 ;

~214 37 726 CAL a 0215 AC 72~ MOW ROY

0217 OF 7~9 ADD AWRY

13~ ;
733 ; NOW Gel lf~ClP. - (.75 (SELECTED f-lLTUtJ) 73~. ;
AYE B82~ 735 MOW ROY

Or/20 70 740 ADD AWRY
0221 F6~5 741 JO Fast JUMP IF PYRE GOOD
0~23 4'.CF 742 REJECT: JUMP Output I Ox 743 FAST: IN Apple 0226 5303 744 AWL Aye 0~28 03FD 745 AD Aye AYE EYE 14b JNZ COO JUMP If IT EQUAL 3 022C Eye 747 JPU' Swallowtail

7~g ;
749 ; NOW CHECK FOR FAST OR SLOW Output FILTERS
150 ;
O he B~32 751 CKFO: JO FAST
0~30 4491 752 JUMP SLOW
0232 ~32S 753 Fuzzier: MOW ROY GENERATE PROVE OUT FLUTTER /32)+PfJtlOD CNT/32u234 FOX 754 OW hero THIS IS ACCOMPLISHED BY TOE FOLLOWING
755 ;
75b ; Foxily PUT Output Flutter IN Rb,R5.ACCU~
757 ;
0~35 AH 75S OVA Bra 02'3b C8 759 DEW ROW

023g AD blue COVE HA
0239 C3 7~2 wreck ROW

76~ ;
76S ; NO Shill RIGHT 5 TIMES
766 ;

023D 30 7b8 XCHD AWRY
EYE 47 7b9 SWAP A

-~18- ~;~Z8~
ISIS-II MCCOY MACRO ASSEMBLER ~3.0 lHlS FILE ON DISK (R2010)-P(UTI~ Steven STONE
LZ~C ODE LINE SDURI;E STA~EME~lr 023F AC 770 MY ROY ;LSD/16 0240; D 771 MOW AIRS
0241 18 772 lot ROW
02~ 0 ?73 XI~ID no O
0243 47 774 So 0244 A 775 MY ROY ;MB/16 0245 27 776 CUR A '' 0247 47 Tf8 SWAP A
~)248 30 779 XCHD AFRO ;~lSB/lb 780;
781; NO Royalty 1 IIPIE RIGHT ANTI COMPLIANT
I

024C 37 786 l.PL I

024F by 789 ARC A

0251 AD 791 MY US. A
V'252 FC 7~2 MOW AWRY
0253 by 793 RKC A
025~, 37 794 CAL I
02$ ~32b 795 SKIP: MOW ROY ADD 3 M081 SIN IF ROTATED EIGHTS TO PREY FIT FLUTTER CUT
0251 60 796 AUDI AFRO EFFECTIVELY 6~ERAl'lNC PROVE WIT FLYWEIGHT
0258 ED 7g7 XCH AWRY
02$9 18 IY8 IN ROW
AYE 70 79g A'JDC rural) 025B YE 800 XCH Aruba EYE IF 803 TV R7.1`
804;
805; NOW or 1/32 I NEW AND ADD TO 31/32 OLD
80b;
()25F B82B 807 MOW RUDY FRY SHIFT R16HT 5 TIMES

0265 Ad 812 Levi ROY
02b6 C8 8l8 ICKY ROW
0'267 FOX 814 MOW AWRY
02b8 P8()3 815 OW ROY
816;
817; No SWOOP RIGHT 4 Lucy 818;

026B 47 ~20 SWAP A, 026C AA 821 MY ROY ;LSB/16 0'26D Fly 822 MOW AWRY

u2~F 30 824 XCHD AWRY

I
lSlS-Il MCS-48/UPI-41 MICRO hSStMBLLR~ V3.0 THIS flue 0~1 FISK IR2010)-AUTHOR STEVEN STONE
LOO OX LINT SW ROE Statement 0270 47 8~5 SWAP A
0271 A 826 MOW R3,R MCKEE
0272 I B27 CUR r 0/78 2C 828 XCH ~,R4 02?4 47 ~29 Slop r OOZE 30 880 XCHD awry ~31 ;
832 : NOAH hotel I TIME RIGHT
;

02 n FC ~85 MOW AWRY
0278 by 836 ARC
0279 I ~37 OVA ROY
027h FE ~38 MOW AWRY

0~7C A 840 MOW ROY
027D FUR B41 HO ~,R2 OF ~326 848 SKIP: MOW Howe ROD 2 YOST SGNIF RUTTED Owls TO PREVIOUS BYTE SUM

0286 A 849 MrUV ROY
0~37 18 850 IN ROW
0~3 FC 851 MOW AWRY

AYE A 858 MOW owe 85~7 ;
X55 ; CHECK Fox OVERFULL. IF Carry SKI TONY ffhKE Flutter FFFFFF
85b ;
02B0 EbCF ~57 JUG Output 028D B~58 858 CLUE MAKFF
028F 44CF ~59 JUMP OUTPUT
~60 ;
blue ; THIS IS SLOW OUTPUT FILTER
8b~ ;
8b3 ; THIS R WINE IS A .b64HZ CORNER FILTER FUR
8b4 ; TOE OUTPUT SLOW Flowerier 865 ;
~6b ; FIRST GET 12/~OU~PUI/128 8b7 ;
clue S826 868 LOWE: M W ROY
0~3 F7 by RLC A
0294 lo 870 IN ROW

02~6 Fly B72 RLC A
0~7 37 8~3 CAL Q
02~g AD S74 tlOV ROY
0299 18 8~5 ICKY 1~0 - 02?B F7 877 RLC
029C 37 878 CAL h 02~ 879 TV ROY

-50_ I
ISIS-II MCS-48/UPI-41 MACRO ASSEMBLER, V3.0 N
this FILE ON DISK AUTHOR Seven Steinway LOO (18~.1 LINE Swallower STATEMWI
02~ 27 go CUR A
029F F7 8~1 RLC A
AYE 37 13~2 WE ,.
AYE A ~83 MY ROY
884;
go; HOW SUBTRAtl 1/127DUTPlll Fruit OUTRUN
I
QUEUE B82~ 887 Levi ROY LO OUTPUT FILTER
AYE FOX ~38 MOW AWRY
AYE by 8~9 ADD AIRS
AYE AD 890 MY R5,~

AYE FE YO-YO MY OR
awoke 70 8q3 ADD Atari urea, AH 8q4 MY ROY
02~ 18 8q5 IN ROW
AWOKE FOX 89~ MY Atari AUDI OF 8q7 ADD AWRY
KIWI A 8qg MY ROY
~qq;
900; NO, GET 1/128 OF NEW DATA AND ADD TO 12//12~0LD
queue;
02AF By go MY ROY

02B2 F7 queue RLC A, )2~3 18 905 IN ROW
02~ FOX 906 MOW AWRY

02~6 RAY 903 IVY ROY
02117 18 okay IN ROW
02BC FOX 910 MY Atari 028q F7 911 RLC AYE
OVA AL 91~ KtlY ROY
02Sû 2/ 913 LO A
021~ F7 914 RLC A

glue;
917; NOW ADD DATA
91g;
BYWAY Ebb 919 Ivy ROY

SUE ED ~21 ADD AWRY
02C2 A 9~2 HO ROY

02i;5 YE I ADIEUX Aruba 02Cb A 92~. HO ROY
02C7 I 9~7 IN ROW
02cg FC $23 MtlY AWRY

Allah no 930 IVY ROY
931;
932; CHUCK FOR OVERFLOW. IF CAY SET THEN fluter =FFFFFF
02CB E6CF 9'~4 JNC OUTPUT

- 5 1 - ~L22 ISIS Swahili MACRO ~SEMBLER, Yo-yo THIS FILE Disk RIO ATARI STEVEN STONE
LOO l)BJLINE USE Statement by 937; ho DO RECK OR OUTPUT FILTER EYING SLOW trough I row LUCILLE OUTPUT SO SIGNAL STOPS
q39;
q40 . Flh~ST CHECK I NO MOTION SIGNAL ON P2-7 DOZILY) 941;
02CF do 942 WTPUT: IN APE
02~0 FOE q43 J97 ALE Pi IF NO MOTIF
OILY q44 TV m,P23H Gut MOB OUTPUT FILTER

02L~ Gel 946 JO DSR9LE :J11P IF MOB JO
0~1~7 FOE 947 AWL AYE

02DC. FOX q50 MOW Amy ODD 0~7 q51 ADD APE
O2L1F FOE 952 .1C Craig IMP IF GREATER
95~;
954; OUTPUT FILTER <15HZ SO DISABLE orrPuT AND SET LOWE GAIN
955;
EYE AUDI 95b DSRBL~: AN P2.tOD7H

02t5 g410 958 CRAG: JUMP CAGE
9~9;
~60;
0400 ~61 OR Us 962;
963;
0400 9~33tl 964 POW: MtlY ROWLEY ETA STOPPED FLAG

q66;
967; ALSO Rest IDEA FLAG AND SET
960; OLD FAST FILTH TO POOH 256D
~69;
0~4 18 ~70 ICKY rho 040LJ BOO 971 pry ought Rosetta FLAG
0407 Sue 9/2 OVA ROY

0409 It 974 IN ROW

040~ 0454 976 JUMP HAIR
977 ;
978 ; IS OUTFIT FILTER > OH IF SO Enable OllPUT
9~9 ;
0410 BUD 98~ CK~Gl~ RUDY CHECK FOX STOPPETJ FLAG
0412 FOX 981 MY awry 0413 C619 ~82 JO annul ;JNP IF NOT STOPPED
9~3 ;
984 ; No Do Slopped fi~luTINE
I
0415 D400 986 CALL STPOJl go 0419 AYE 989 ANNUL: AL P'27~0BH TENABLE WTPUI THIN Ho ISIS SHOP MACRO ASSEMBLER. V3.0 THIS FILE ON FISK ~R2010~-AUTHCR STEVE STONE
LOO OBOE LINE Of STATEMENT
So 991; CK75 IS A R0UTlNt' THAT Stats COIN HIGH lo tlnPUT
~92 ; FILTER VALUE IS >75HZ ELSE GAIN IS SET LOW
041~ D491 994 CALL CK,75 I
q97 ;
9~g ;~*~ I I
qqq;
1000 ; NOW DO SU~RnUTINES
1001;
1002 ;~**~*~*~*~ **~*~ *~*~*~*~*~*~ **~**~*~*~*~ **
1003 ;
Q41F Do 10C4 PYRE: SOL RIB SUE REClSlER5 ~4~0 A 1005 OW Rl7A SUE ACT MOLTER
10~;
1007 ; IF OVERFLOW CUR Fly 100%;
0421 2624 10~9 Juno LATCH
04~ A 1010 CUR Fly 1011;
1012 ; NOW LATH END I IN NEW PERIOD COUNT
1013 ;
0424 9AFC 1014 LATCH: RNL P2~C~'CH
0426 BYWAY 1015 OWL ~2.~03H AIDERS CCNR1~L
04~S 23%0 1016 M0V AYE
AYE D48S lilacs CULL CON
042C 91 1018 HOAX it'll LATCH PERIOD CENTER
042D 9RFE 1019 AIL P2,1tOFEH;~ODRESS Colorer 2 042F 81 1020 MOVE Plower TREAD CONNER 2 LYE
0430 37 1021 CAL A ;SUUTRhCr Frill OFF
0431 AC 1022 MOW ROY Stewart Period Clint 04~ 81 10~3 tweaks AWRY ROARED COURIER 2 MY
0433 37 1024 CAL A Saddlers FROM OFF
0434 AD 1025 MOW ROY STY PERlrJD Count 102b:
1027; NOW LOUD MODE INTO C~liJNTER
10-~ .

1030;
1031; NfJ~I RELOAD Queller WITH DELAY FOR INTERRUPT
1032; SERYlCE'rlME
10~3;

0439 EDDY 1035 MOW AUDI ;RELOALI LS8 COUNT LESS Delay 043g 91 1036 IIOYX ROY
043~ 23FF 1037 MY A.~OFFH RELOAD ISSUE CENT
EYE I IWB PUCKS ~Rl.h 043F YE 103q CALL SCOFF
1040;
1041; IF PROGrtA~I Salk IS Paneling A CALL PERIOD
1042; Instruction THEN YE STACK VALISE
104~;
0441 1)809 1044 CKSrAC: no ROY

ISIS SHOP MACRO ASS~DLER. V3.0 lHlS FILE ON DISK (WRITHER STEINWAY STONE
LOO OX LINE SWRlt STATEMENT

0444 5307 1046 AWL Allah 0448 9~2 104~ JNZ CKSM
044~ C8 1049 BE ROW

044C AYE 1051 Zoo h,~LOM CLAP

10~3 ;
1054 ; Chant ADIPOSE IN Slack 1055 ;
0450 B07C 1056 JOY PULL. KELP
10~7 ;
1058 ; NOAH CHECK FOR PERIOD 'fox SMALL Lowe 256) 1059 ; IF LESS TON LOAD R3-4 FROM Rb-7 10~0;
0452 fed 1061 CKSM: MY AWRY
0453 ~659 1062 JO CLOVE

0456 I Lou MOW ROY
04~1 of 1065 OVA Allure 1067 ;
1068 ; FlRSl RUSS TIMER ELAN
1069 ;
045~ 00 1070 CLOVE: NO
04~ 00 1071 045~ 00 1072 NO
045C EYE 1073 JrF NIX
1074 ;
1075 ; SET NOAH PERIOD FLAG
1076 ;
EYE B~3C 107'1 NEXT OVA RUSSIA
0460 BOO 1078 MOW QRO.~I
107~ ;
loo ; IF I IS CUR THEN OVERFLOW ON COUNTER MAKE FRIED OFF
10~1;
0462 766g 1082 GO: JFl MD
0464 23FF 1083 COVE A,.#OFFH

0468 85 1036 CAL Fly 0469 quaff 1087 ART: NO P27#0F8H;kESET LEVEL DETECT PI COURIER Address 046B OF 10~ OVA A.~OFFH
046D 62 1089 OVA TEA RESET INnLRRUPT C W MAR
EYE F9 1090 HO hi fryer Accumulator 046F C5 1091 SOL ROB reseller REGISTERS
0470 8~0~ 1092 OWL R2,10511 04~2 93 Luke RET RETURN
Ivy Jo HUH *I *~***~*~*~*~*~*~*~**
1095;
1096 ; THIS hOUTlNE RESORTS THE PYRE AN FILTER So Luke ;
04/3 U81E 10~9 REEQUIPPED: MOW ROY err Frown INFO

I
I
ISIS-II MCS-48/UPI-41 MICRO SOMMELIER. V3.0 Thus FILE I DISK WRITHER SEVEN soon LOO OX LINE SOURCE Statement Q4/5 BOO 1100 OVA R3~0 CLARA LOW BYTE
0477 FOX 1101 MOW AWRY gel MY
0478 I llQ2 MOW ROY

try fox 11~1 MOW AWRY Gin MOB

047C BOO 1106 RfCOF: MOW R27~0 CLARA POWER REG.
1~07 ;
1108 ; IF NUDER TO BE CXNV~RTED IS C 256 THEN MAKE 2~6 1109 ;

047F 9686 1 ill LIZ CK4 0481 27 ill CUR A
04~2 A 1113 OVA ROY
04~3 AC 1114 COVE R4,~

111/;
~118 ; NO CHECK FOR BEING AXLE TO SHIRT 4 TIMES
1119 ;
0486 53FG 1120 CK4: AWL A.#OFOH
0488 By 1121 JNZ SHOWOFF MY IF 4 Shifts 1122 ;
1123 ; NOW Shill 4 TO lye LET
1124 ;

048D 47 1127 Syria A
joy AD 1128 MOW ROY
048f FC 112~ MOW AWRY
0~90 47 1130 SUP
04~1 30 1131 XCHD AWRY
04~2 AC 1132 OVA ROY
04~3 Lo 1133 be ROW

04~6 30 1136 XCHD AWRY
04~7 A 1137 MOW ROY
YO-YO BYWAY 11~8 MOW R2,~4 Q4gA FED 113q MOW AWRY
1140 ;
1141 ; NOW Shift I Al A TIME TILL BY
1142 ;
~49B FOE 1143 SHOWOFF: JC7 DONE ;JMF IF L~FI JUSllFlED
Q4~D IA 1144 IN R2 04~F FOB 114b MOW AWRY
owe F7 1147 RLC

04~2 FC 114~ COVE AWRY

04~ F7 1153 RLC A
O My ED 1154 Jo R5,~

lSlS~ SWOOP MACRO ASSEMBLER V3.0 ` - -THIS FILE ON DISK l~cO10)-~UT~DR STEVEN INN
LOO OX LINE I E Statement M A 849B llS5 JUMP SHOWOFF
115~;
1157 ; NO Gel READY TO OUT # We OF TALL
11~8 .
AYE C~7 1159 DONE: CUR C

04hC F/ 1161 hLC A MULTIFOIL BY 2 FOR
AUDI AD 1162 JOY ROY no Byte TABLE
AYE 0300 11~3 Do ho RTBL
04B0 I lob MYOPIA Q-Q~

04~2 ~301 1166 MOW ALLAH RTBL~I
04B~ by 1167 ODD hers 04~ I 1168 M~V~3 AYE
W AH 11~9 MOW ROY
Okayed ~31F 11/0 NO A~#IFH SAVE Walt BIER

BYWAY Aye 11/2 JUMP ROY
1173 ;
1174 ;

1176 ;
1177 ;
1178 ; Jo DtClDE HO MANY TIMES To ADD THE ADDER
117~ ;
0500 I 1180 Regatta: MY AWRY

0~09 LEO 118/ Hal Await CLARA ADDER sirs sob AH 1188 MOW R6.h EYE 27 11`70 hDDLR: CUR A
050F 6B 1191 AUDREY: ADD AWRY
0510 LCUF 1192 Owls Redrill 0516 EYE 1197 FNL Aye CLARA ADDER DOTS

AYE 23FF 120(J Levi A.#OFFH

Oslo A 1202 MY ROY
EYE Dry 1203 ADO: TV R5.~0 CLARA LOW BYTE
1204;
1~05 . NO ADJUST R~ÆR REG. R2 FUR FINAL SHlFr 12~6;
0520 FAX 1207 tlOV h.R2 0~21 37 120'd CAL A
~5~2 0307 1209 ADD Q.47 ;7-~6 If 2'S Clip SUE SHEA Wylie AWRY Assailer. V3.0 - -IRIS FILE ON DISK (WRITHER Seven Stone LO OBJ LINE SOURCE Strom 0525 C64C 1211 JO DOW elf O NO 8HIFlS
0527 E U D 1212 JNC SLY IF NC THEN I- SHIFT Left 1 1~13 ;
1214 : NO CHECK FUR OUZEL SHIFT OX 4 121~ ;
052i Or~FC 1216 A W Aye 052B Eye 1217 JNC fly 121~ ;
121~ ; No SHIFT MY 4 1220 :

EYE B$06 1222 OW ROY
0530 FOX 17~3 MOW I
0~31 30 1~4 XCHD ROY

05~4 FE 1227 MOW AWRY
05~ 18 1~28 ICKY ROW
0536 30 12~ XCHD lo 05~8 AH 1231 OW ROY
05~ 27 1-~32 CUR A

053~ 4/ 1234 SWAP A
05~C 30 1~5 XCHD CRY
05~D Fax 1236 MOW AWRY
EYE C64C 17~/ JO DONE
0540 I 1238 Shuffle: CUR C
0541 OF 17~9 OVA Art 0543 A 12~1 OVA ROY

054b YE 1244 OVA ROY

0548 by 124b ARC a 054~ AD 1247 ilOV USA
aye EYE 1248 DJNZ R2,SIIFl 054C 83 124~ Dowel: Fret 1250;
054D 97 1~51 SLY: Cut C
EYE fed 1252 HO AWRY

0550 AD 1254 MOW R5.f`

0552 F7 12~ RLC A

0555 F7 12.5g RLC A
055b A 1260 IVY ROY
05S1 %3 blue REV
12b);
1263; Isle IS USED To KEEP FlLTElt VALUES BEEN POOH and FFF~H
12U;

% I
Icily MCS-48/UPI-41 MACRO ASSEMBLER. V3.0 5 7 Thus Flyer ON DISK (Roarer STEVEN STONE
LOO OX LINE URSA STATEMENT
0558 23FF 12~5 ~AKFf: OVA A,~OF~I
AYE A 12b6 OVA QRO.Q
055B C8 12b7 EKE ROW
O~SC A 12b8 MOW ROY
055D C8 12b9 EKE ROW
05~5t A 1270 TV ROY
055F 83 In I DUN: RET
1~72 ;

1274 ; Shalt IS USE TO SCALE OWN THE omit FREQUENCY
1~/5 ; no I OF 4 VALUES lTOI-lTO.75-lTO.~68-lTO.231 127b ;
Oboe 88r~b 1277 STALL: MOW Rob GET OuTpllT FILTER
0~b2 FOX 1278 HO AWRY
0~6~ A I n g MY ROY
OSb4 18 1280 IN ROW
OSb5 FOX 1281 MOW AWRY
05bb AC 1~32 OVA R4.r7 OSb7 18 12~3 lNC ROW
Oboe FOX 1~84 OVA AXE
056g AD 1285 RS7A
128b ;
1~87 ; ALSO PUT Output FILIAL VALUE IN R36-33 12~3 ; THIS IS USED US SCM ITCH REGfS-rERS
12~;
OSbA Bæ36 guy MOW Rob 056C F8 1~91 HO AWRY
056rl A 1292 MOW QR07A
byway 18 12g~ IN ROW
05bf FC 1294 OVA AWRY
05/0 A 1~5 M4V EVA
u571 18 12~b fNC ROW

05/-3 A 12~8 MOW ROY
lug ;
1300 ; NO CHECK FOR WHICH SCALY FACTOR IS SELECTtlU
1301 ; Ply Ply SCALE FAKER
13~ ; O O l 10 1 303 ; O I 1 no ./5 1304 ; I O I 10 .4~3 1305 ; I I I TO .~81 130b ;
v574 Ox 1307 ON Apple v57~ ~30C 1308 Hal ASIA
0~77 CbD2 130~ JO Corey JUMP IF I TO I
~579 52gg 1310 Jo P75 JO IF 1 10 .75 1311 ;
1312 ; BIT 3 SET DO .468 SCALE FACTOR
1313 .
1314 ; FIRS to 1/32 IN R36-3S
131~ ;
057B B338 131b P4b3: MOW ROY
057rJ B4D4 1317 CALL SHlFRI
057F ~36 1318 OVA R~7#36H
0581 BYWAY 1319 Grill SHAFER

-58- ~22~
ISIS-I I MCS-48/UPI-41 M~CRCI Salk. V3.0 rHlS Lowe Len DISK (li2010~-AUT~JR SIEVE STONE
LQC OBJ LINE SOURCE STATEllENT
1320;
1321; NOAH Mel .5 I R3-4-5 13~2;
0~3 ~05 13~ MOW ROY
0585 Do 1324 CULL SHAFER
13~5;
1326; NUDGE And .5 TO COMPLEMENTED 1/32 1327;
~587 by 132~ TV ROY
)5~9 FOX 1329 MOW AWRY

058B by 1331 ODD h.R3 05~ A 1~3~ MOW ROY

sty FOX 1334 HCIV aye 058f 37 13:~ CAL a D5gl AC 1-337 TV ROY
0592 18 13~ IN ROW
O~g3 fax 13~ TV AYE
OOZE 37 1~4~ CAL Pi 05~5 ED 1341 And AWRY
059b AD 1342 MY ROY
059/ AUDI 1343 UP QFr2 1344;
1345; NCIIJ DO .75 SCALE FACTOR UNWELL Blue 3 IS IT
THIN 00 .231 1347;
05~ ~2~15 1-348 P/5: Jo ~31 059B By 1349 MY RUSS
OOZED D4D4 1350 CULL SHIFRl 05~r I 1351 11~ ROY
AYE ~4D4 1-352 CULL SHIFRl 1353;
13S4; COY .25 NOW COMPLEMENT Ann add TO Output 1355; FILTER TO JET .75 13~b;
05f~3 r~2~ 13~7 IVY ROY

Ahab 3/ 1359 CAL A
05h7 by byway ADD Aye OOZE I 13b2 IN ROW
AYE FC 13b3 MOW AWRY
AYE 37 13b4 CAL A
AWOKE 70 13b5 ADD AWRY
osnD a 13b6 MOW ROY
I 18 13b7 IN ROW
05aF FED 13b3 ivy AWRY
05B0 37 13bg CAL A
05~1 70 1370 ADD A, PRO
051]2 AD 13/1 HO ROY

1373;
1374; NOAH DO .281 Solute Factor BY GElTlNO .25~(1/32) I
ISIS SHOP AQUARIA ASSEMBLER. ~3.0 - 5 9 -lHlS FILE I DISK (Ann STLYLN STONE
LOO OX LINE S~RCE Sr~TE~r~NT
1375 ;
05U5 8$~3 137b P~81: MOW ROY
05~7 'Dow 1377 CALL SHAFER
Ode 'd836 13/~ TV ROY
05~8 'EYE 1'37~ CALL SHAFER
1:~0; '' 1~1 ; GOT 1/32 IN ~6-38 1382 ; NOW JET I IN R3-5 13~3 ;
05~ aye 1'384 MY ~07~5 05~F B4D4 1~$5 CALL SHIFX1 ox l ~305 13~6 TV ~0.~5 I
1~39 ; NO f4DU .25 fun 1/32 1390 ;
OSC5 ~36 1391 TV ROY

05~8 I 13~3 QDU AWRY
~5~9 fob 1~94 OVA of AYE it 1~95 IN ROW
05CB FOX 1396 MY Awry 05~C 7C 1397 ADD AWRY

OF FOX 1400 OVA f'.. PRO
ODE MU 1401 ADUC Aye DOW All 1402 OVA ROY
05~2 847C 1403 kt-T2: JUMP REEF
1~0~;
14~5 ;
1406 ; Shirk} IS A ROUTINE what SHIRTS 3 REGlSTt'RS
1407 ; TIGHT I PLACE. ROW JUST BE pol~rlNG Sod.
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05D4 91 1409 SHAFER: CUR C

05rR3 1413 DISC ROW

DOW by 1415 I A
DUB All 141b MY Roy 031)C C8 1417 I ROW
05DD FOX 141~ V AWRY
OOZED I 141~ C f`.
05'0F A 1420 MY Roy 1ll22;
14Z~; SHOWOFF IS A ROUTINE what SHIFTS 3 Wrigglers 1~24; RIGHT 4 PLOPS. ROW KlJsT POINT An LOB.
1425;
EYE FOX 1426 SHAFER: Levi pharaoh . EYE 1$ 1427 IN ROW
EYE 30 14Z3 XChU AWRY
EYE 41 142~ S.`~f~ A

ISIS-II MCS-48/UPI-41 AYE ASSEMBLER. ~3.0 lHlS FILE ON DISK (AUTHOR Sloven STONE
LOO OX LO SEIKO S'r~rr-'~ENr EYE 30 1435 XCHD ho EYE 47 143b STAR A

05~D A 1438 MOW QRd7A
EYE 18 14~9 ICKY ROW
Obey FOX 1440 OVA AWRY
05F0 47 i441 SWAP A
OSfl 530F 1442 AWL A7#0FH
0~'3 A 1443 OVA ~R0 05r-4 83 1444 REV
1445 ;
1446 ;
ObQO 144/ OR both 1448 ;
144~ ;
145~ ; STOP IS A RO~nlNE USED 10 TRY hod STOP
1451 ; FALSE Snarls DO no VI~RA'I'ION fed UTTER
1~52 ; ERRONEOUS SIGNALS
1453 ;
0600 queued 14S4 Slot: AWL P2.~0D7N;DISA8LE OUTPUT GAIN LOW
143b ;
Shea ; NO SKI wrpuT FILTER TO ~E~AULl (15H~I
issue ;
~602 Eye 14S8 M W ROY

Oboe 13 1460 IN ROW
0607 ~08f~ 1461 OVA fdR~7#080H
0609 18 14b~ IN ROW
AYE ~fJOI 14b3 MOW fry 1464 ;
1465 ; So Phrasal MODE
t46~ ;
060C I 14b7 CUR FOX
060D 95 14b8 CAL FOX
1469 ;
1470 ; IF Surfer FIST FILTER IS SELEClLD lien Rightful 1471 ;
fDbOE 09 1472 IN Apple OtOF ~303 1473 RNL Aye 0611 03FD 1474 ROD Aye Q618 9617 14'15 JNl OVA JO IF NOT SELECTED
Obl5 C4b4 1476 IMP CLRSTP
lo 3 1478 ; IS Purl Oval Sty 1479 ;
0617 3b6~ 148~ Ott: JOT CL~CTR JUMP IF SET
14~1 7 1482 ; IS NEW PERIOD Flog SET
1453;
Obl9 3$3C 1484 MOW REWAKEN

Isles MCCOY/ WI-41 MACRO ASSEMBLER. ~3.0 THIS Flue I FISK (k2010)-AUTHbR STEVEN STONE
LQC QriJ LINESU`lRCE STArE~ENT

Obloquy C670 143b JO RETURN Jump IF NUT SET
Ogle BOO 1487 MOW ROY CLARA NEW Period Lug 14g~ ;
1489 ; NEW Pickled Flog per sup DO Slopped ROUTINE
1490 ;
1491 ; NOW GET 7/~3 OLD PERIOD TO ADD TO CAMP NEW
14j~ ;
Obeyer IFFY 1493 MOW ROUGH FIRST JET 1/8 NEW
0~22 97 1~9~ Cur C
Oboe FOX i495 MOW AWRY
Oboe 67 14q6 F~C A
Oboe AD 1497 MOW AYE
062b C8 14~3 DEW ROW
Oboe FOX 14~9 MOW AWRY
Oboe by 1500 ARC A
u62~ AC 1501 MQV ROY Noel 15g2 ;

06iB FED 1504 OVA AWRY
Ob2C 67 1505 ARC A
Obeyed A Ion MOW R5.
byway FC 1507 MOW AWRY
Ob2f 67 1508 F~C A

1510 ;
06~1 97 1511 CLUE C
Oboe FED 1512 MCV Awful Oboe 6-/ 1513 ARC A
0634 37 1~14 CAL A

Oboe 67 1517 ARC A
06~3 37 1518 WE A EYE AND COMPLEMENTED
151~ ;
063q 60 1520 ADD AWRY
Oboe AC 15~1 OW R4.h Obeyed 70 1524 ADD AFRO
Oboe A 1525 OVA AYE NEWMAN
1526 ;
1527 ; NOW US 2'S COUP ON 7/8 NEW
1~3 ;
063F I 15~ OVA AWRY
Oboe 3/ 1530 CAL A
Oboe glue 1531 ODD Allah 0643 AC 15~2 OVA R4.
Oboe FED 1533 MY AWRY
Oboe 37 1534 CAL A
0~46 1300 1535 ADD QUEUE
0648 All 1536 OVA ROY
1~37 ;
15~ ; NOW TAKE OL~-7/8NEW AND CHECK OR P~SlTlVE RESULT
1539 ;

- 6 2 - ~L2;~7 ISIS-II I~S-1)8/UPI-41 MACRO AS~MEILER, 'i3.0 THIS FILE ON DISK (WRITHER STEVEN TUNE
LO OBJ LINE SIRIUS STATEllENI
0649 ~30 1540 Levi ROY
064B FOX 151l'71 MOW Allah 064D 18 15~773 IN ROW
EYE 1:0 1544 ItOV AYE
064F ED 1545 ADbC AWRY
1~46;
1S47; IS RESULT POSllIVE
I
lo Eye YO-YO JNC INCH IT I NEGATIVE
15~0;
1551; it'll IN USE SUPS CNlR
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(~652 Lucy 1553 TV ROY
06~4 10 1~4 IN PRO
1555;
ISSUE; No IN TOTAL Suits ANTI
~57;
I 7d~5 15iB INCH: MOW ROY
0657 10 1559 IN QflO
15~0;
1561; Cheek FOR loyal > 32 1562;
0658 1:0 1563 MOW AWRY
I OWE l~b4 AUDI Aye 06513 L67() 1565 JNC flatiron Alp IF C 32 1~66;
1S67; No Shylock IF hull Ctl~DITlONS I
1568; SrMTUP HAZE OCCI!RED
1569;
1570; NOW CHECK OF SO POST RESULTS
1571;
(165D Do 1572 IVY ROY
065F hi 1573 IVY Awoke byway 0~7 1574 ADD Aye 066~ EYE 1~75 JNC CLRCTR Jo If L~SSC80X PUS
1576;
157/; NO, CUR Slop FLAG AND LNAE;LE Output IS/3;
06~4 ~33D 157q CLRSIP: JO RUDY CLEAR Stopped FLOG
0666 ~000 1~80 HO RHO
06b8 AYE JOY OWL POW TENABLE OlJrPUT COUNl~R
1582;
15~ J a PULL CENTERS
1~84;
066~ 27 15J5 CLRC~R: CUR A
066B ~34 1586 PEEVE ROY
066D A 15~7 HO QRO,A CLARA PUS SUMS CNTR

Oboe A 1589 I QllO,~ CLARA TOrPL SUMS CNTR
I
1S91; I, WRITER Frill Subroutine Ij92;
0670 I 15q3 RL1URN: FIT
15~4;

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LOO OOZE LINE SUP Stamina 15~5; sETcolsr-Tcl AND Syria ARE ROIJTlNES THAT syrup 1596 ; OR INITIALIZE THE COU~TEkS OF THE 82s3 1S97;
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1610 ; SKI W Queenlier I
1611 ;
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oboes 83 Ibl5 or 1616 ;
1617; STY COUNTER 2 1618 ;
068s Sue Ibl9 SLOT OWL P2,K3H
0687 ~3~0 1620 ova AYE
068~ 90 1621 ox I
oboes I 16~22 or 1623 ;
Ib24 ; CON ENNUI s 82s3 l62~ ;
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Ib29 ; CHECKOFF ~lsAr~LEs 82s3 1630 ;
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1637 ;
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06~3 FOX 1639 ova AWRY
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AYE 9AIJF 1649 LUG: AWL P2,tOl)rH

ISIS SHOP MACRO Assembler. V3.0 ' - 6 4 -THIS FILE ON BOYCE t22010)-AlnHOR Seven Soon LOO o'er LINE Surety STATEMENT
ObAb 8'8 1bSO JET
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0700 85 1662 SUPER: CUR FOX
0/01 I Ibb3 CAL it l bb4;
lb65 ; NO JET 7/3 OLrl 1/8 NEW AND PUT IN rust Flutter I bob;
lbb7; FIRST GET 718 OLD
lbb8 ;
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0708 FOX Ib74 M W AYE
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IBM ;
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lb81 ;
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0715 B8~4 1686 MOW ROY
0717 B4D4 Ib81 CALL SHAFER
lb88 ;
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07~0 FOB 169/ OVA R.R3 0722 70 16~ ADD Q.~RU

0724 I 1701 MOW R8.h 0725 FC 17V2 OVA Q.R4 072b 37 1703 CAL
0721 /0 1704 ARC ho ISIS-II Sly 41 Macro ASSEMBLER VOW
THIS FILL ON DISK (Roarer BTEVE'Il Stove LOO OBJ LINE URSA Statement v/28 I 1705 OVA ROY
170~ ;
1707 ; NO GET I NEW. TO drywall TUG 7/$ OLD
l/v~3 ;
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1715 ;
171b ; Null ADD
1717 ;
0735 '~32v 1718 Lowe ROY
0737 Fax 171? MOW awry 0738 by 1720 add AWRY

073B fob 17~3 MOW ~.R3 073C YE 1724 Audrey AWRY
v73D I Ire OW ROY
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173v ;
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074S d82~ 1740 SUPER: MOW ROY

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1751 ;
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ISSUE MCS-98/URI-41 Myra Assembler. V3.0 THIS FILE ON DISK IR'2010)-AUTHOR STEVEN STONE
LOO OBJ LIVE 501l~CE Statement 0/5B FOX 176~ Levi r.... pro 17~2 ;
1763 ; OLD IN REV. 2.3.4 NOAH OUT 1/8 OLD
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0765 ~804 176q MY ROY
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Irl3 ;
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07~F A 1779 TV I
07~0 I 1780 TV I
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1789 ;
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0/79 d807 179~ MOW ROY
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077U d~V7 1794 OVA ROY
017f BYWAY 179~ CALL SHAFER
0-/81 B807 179~ MY ROY
0/~3 D401l. 17~7 CALL SHlfRl 1798 ;
1799 ; NOW AD
1800 ;

0787 Fry 1802 PEEVE ANN
v788 by 1803 Aye AWRY
07~9 M 1804 OVA ROY

G788 fob 180~ MOW AWRY

0/~0 A 1808 OVA ROY

078f fC 1810 OVA AWRY
0-/'~0 OF 1811 ID AWRY
-1~1 P10 1812 Levi I
1813 ;
181~ ; CHUCK FUR OVL~FLOW (MAKE FFFFFF) ISIS Icily 1-41 MACRO DORIA V3.0 Lowe FILE ON IJISK lh2010)-llUTHOR STEVE Rune LOO Owl LONE SOUR 8TATr-11ENr 1815;
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0310 787C 1834 row 30344 0312 7798 183S OW blob 0314 7b~ 1836 Dull 304:2 031b 75FC 1837 DO 30204 0318 751C Ig~8 DO 29980 ;140 AYE 7438 Ig3~ Do 29752 031C 7~7C 1840 OW 29564 EYE 72~ 1841 DO 2~b ~20 711~3 1842 OW I 4 0322 71~8 1843 Us 28~52 03~24 7u5C 1844 DO 287b4 0326 bF78 1845 I 28536 0328 b~88 184b I 28344 AYE 6DF4 1847 0~1 28148 OKAY byway 1848 DO 2/992 ;150 I 6C98 18~ 0~1 27800 0330 blued 1850 Dull byway 0332 b814 1851 Dull 27412 0334 b~78 1852 DO 2725b Ahab 69r~4 1853 Do 27060 03~8 byway 1854 Do 26900 033h b878 1855 DO 26/44 033C byway 185i5 . OW 2~48 OWE b714 18S7 OW 2b388 0'340 b614 1858 DIP 2bh8 IBM
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THIS FILE ON DISK ~R201d)--AUT~R SIEVE STONE
LUG ODE LINT SUE STAT~MENr 03~ 5F54 18/0 DO 24404 035~ 0 1~71 242 O~SC EYE IS/2 row 24112 EYE 5DB4 18/3 OW 'f39gS3 0360 5D10 1874 Do 2~824 0362 5C90 1875 OW 23b9b 0~64 5~1~ 1876 DO 2356~3 03b6 5S30 1877 DO 23440 03b8 5B10 1878 DO 23312 Lowe AYE AYE 1879 OW 231g4 036C ~10 188V DO 23056 0~6~ 5990 1~31 Do 229~B
03/~ 5~1~ 1882 OW 22800 u3/2 ~90 1~83 22672 03~4 580C 188~ flu 22540 V376 EYE 1885 OW 2244~
0378 573U 1886 Do 2232U
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038C 5~C 18~6 DO 21196 OWE 5270 1897 Do 21104 0390 ILK 1898 DIP 20~72 ;200 Om~1s3C It OW 2~376 03~4 512C 1900 Do 207)~0 0~36 50D0 1901 DO 20688 0198 504C lqV2 DO 20~

03~C 4F8C 1904 DO 20364 EYE 41:2C l905 DlJ 20268 03~0 4~CC lg()6 low 20172 (AYE EYE 1907 Dull 20076 03M 4t0C 19U8 DU 19980 ;210 AYE 4D~C Icky DO issue 03~8 4D~C 1910 Do 19785~
03M OKAY 1911 DlJ 1~692 AWOKE 4~8 1912 [11~1 19592 AYE 4C4C 1913 Dull 19532 l~38;2 icky DO 1~?:340 03B6 Allah 17 DO 19144 03B8 4h8C 1918 Dull 19084 ;220 BYWAY 4P~C 191~ DO 189gg EYE 49~C Isle DO 18~28 . KIWI 492C ln2 DO 18732 0~f~2 4&C8 I 186;3~
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03~6 ~14g~g4q Do 16712 0~8 410~ 1~50 DO 1664 U3EC 4U~3i~52 DO 16520 FOE 4043l9'J3 Do 1645 195~ ;
lqS5 END
USER S`fM~OLS
AD W edit 050t AUDREY OSSIFY A 04~q JACK AYE KEEP 002R CLAP AYE CK4 043 CK'/5 KEG OWE CAGE 0410 CKfO Utah- CLUE OlFq CLAUS 06~f CLUE 045~ CKSNKE Owls CKS~ 045~CKSlAC 0441 CLr~Cl'R U66A CUtSlP Oboe CNTltL 013b Cohn 0066 Cuff EYE SHEA 068S
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WINDOW PICA
QSSL~I~L~ COMPLETE. NO EGRESS

Claims (29)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A tracking, variable Q bandpass filter apparatus for processing an IF signal from a radar transceiver or the like and comprising: period counter means responsive to said IF signal for developing a digital period signal corresponding to the period of each of selected cycles of said IF signal, and low pass filter means coupled for response to said digital period signal for producing a filtered signal which substantially follows said digital period signal thereby substantially simultaneously tracking and filtering said IF signal.

2. Apparatus according to claim 1 and further including conversion means for converting said filtered signal into a display signal having a value corresponding to the frequency of said IF signal.

3. Apparatus according to claim 2 wherein said radar transceiver comprises a doppler radar for determining the speed of a moving body and wherein said converting means further comprises calculating means responsive to said filtered signal for producing a display signal corresponding to the speed of said moving body in accordance with the value of the IF doppler signal produced by said radar transceiver in response thereto.

4. Apparatus according to claim 1 wherein said low pass filter means comprises a digital low pass filter having a controllable effective corner frequency and further including corner frequency control means coupled with said period counter means and with said digital low pass filter for controllably varying said effective corner frequency in a predetermined fashion in accordance with the amount of variation in said digital period signal from one selected cycle to a successive selected cycle, thereby substantially tracking said digital period signal.

5. Apparatus according to claim 4 wherein said corner frequency control means comprises sampling means interposed between said period counter means and said digital low pass filter for periodically sampling said digital period signals.

6. Apparatus according to claim 5 and further comprising inverting means interposed between said sampling means and said digital low pass filter for converting each sampled digital period signal into a digital frequency-related signal.

7. Apparatus according to claim 6 wherein said digital low pass filter comprises filtering means responsive substantially only to ones of said digital frequency-related signals which are within said effective corner frequency for producing said filtered signals comprising signals substantially the same as said digital frequency-related signals which are within said selected corner frequency thereby simultaneously tracking and filtering said digital frequency-related digital signals.

8. Apparatus according to claim 4 wherein said digital low pass filter further operates in accordance with a preselected transfer function which defines the effective corner frequency thereof and wherein said corner frequency control means is operative for varying said transfer function in a predetermined fashion.

9. Apparatus according to claim 6 wherein said corner frequency control means further comprises at least two reference low pass filters coupled to receive said digital frequency-related signals and each having a predetermined, but different effective corner frequency and comparing means responsive to the variation between the outputs of said reference low pass filters for controlling the variations in the effective corner frequency of said digital low pass filter.

10. Apparatus according to claim 9 wherein each of said reference low pass filters comprises a digital filter.

11. Apparatus according to claim 9 and further including window means interposed between said digital low pass filter and said inverting means for rejecting signals from said inverting means which vary by more than a predetermined amount from the output produced in response thereto by a selected one of said reference low pass filters.

12. Apparatus according to claim 9 wherein said comparing means further includes selecting means for selecting the output of one of said reference low pass filters for use by said window means.

13. Apparatus according to claim 12 wherein said selecting means is further operative for selecting the effective corner frequency of one of said reference low pass filters as the effective corner frequency of said digital low pass filter.

14. Apparatus according to claim 13 wherein said selecting means is responsive to said comparing means for selecting the output and the effective corner frequency of the one of said reference filters having the lower effective corner frequency when the variation between the output signals produced by said reference low pass filters is less than a predetermined amount and for selecting the output and effective corner frequency of the one of said reference low pass filters having the higher effective corner frequency when said variation is greater than or equal to said predetermined amount.

15. Apparatus according to claim 1 wherein said low pass filter comprises a digital filter including register means for storing a sample value of a digital input signal; and calculating means for producing said sample value in accordance with a predetermined transfer function comprising the sum of a first proportion of a previously stored sample value added to a second proportion of the present value of said digital input signal, and selecting means responsive to predetermined control signals for selecting said first and second proportions; said sample value comprising said filtered signal.

16. Apparatus according to claim 15 and further including transfer function control means responsive to said digital input signal for producing said predetermined control signals.

17. Apparatus according to claim 16 wherein said transfer function control means comprises at least two reference filters each comprising a digital filter operating upon a digital input signal in accordance with substantially the same form of transfer function to said first digital filter and each waving different preselected first and second proportions associated with said transfer function;
and comparing means for comparing the stored sample values of said reference filters and for producing said predetermined control signals for causing selection of the preselected proportions of one of said reference filters by said digital filter selecting means in accordance with the variation between said reference filter sample values.

18. Apparatus according to claim 17 and further including inverting means interposed between said period counter means and both said digital filter means and said transfer function control means for converting said digital period signals to digital frequency-related signals to comprise the digital input signal to both of said digital filter and said transfer function control means.

19. Apparatus according to claim 18 and further including window means for rejecting any digital frequency-related signal which varies from the output produced in response thereto by a selected one of said reference filters by more than a predetermined amount.

20. Apparatus according to claim 19 wherein said selecting means is responsive to said comparing means for selecting the preselected proportions of the one of said reference filters having a lower effective corner frequency when the variation between the output signals produced by said reference low pass filters is less than a predetermined amount and for selecting the output and the preselected proportions of the one of said reference low pass filters having a higher effective corner frequency when said variation is greater than or equal to said predetermined amount.

21. Apparatus according to claim 20 wherein said comparing means includes means for delivering the output signals of the one of said reference filters whose preselected proportions are selected for use to said window means.

22. A doppler radar apparatus mountable to a vehicle for determining the horizontal velocity thereof, and comprising radar transceiver means for transmitting and receiving respectively doppler-shifted radar signals, said radar transceiver means including a local oscillator for producing a local oscillator signal, and mixer means for mixing said received signals with said local oscillator signal to produce a predetermined IF signal; tracking bandpass filter means responsive to said IF signal for producing a filtered signal corresponding substantially only to that portion of the received doppler-shifted signal corresponding to said horizontal velocity;
switchable power supply means for said radar transceiver means and control circuit means responsive to a first predetermined control signal for switching said switchable power supply means to an inactive condition, thereby removing power from said radar transceiver means.

23. Apparatus according to claim 22 wherein said bandpass filter means further includes output switching means for selectively delivering or withholding said filtered signal from an output utilization means; and control means responsive to a second predetermined control signal for activating said switching means to withhold said filtered signal from said output utilization means.

24. Apparatus according to claim 22 and further including minimum velocity sensor means responsive to the velocity of said vehicle falling below a predetermined minimum velocity for producing said first predetermined control signal.

25. Apparatus according to claim 23 and further including minimum velocity sensor means responsive to the velocity of said vehicle falling below a predetermined minimum velocity for producing said second predetermined control signal.

26. A tracking, variable Q band pass filtering method for processing an IF signal from a radar transceiver or the like and comprising: developing a digital period signal corresponding to the period of each of selected cycles of said IF signal; subjecting said digital period signal to low pass filtering; controlling the effective corner frequency of said low pass filtering in accordance with the amount of variation in said digital period signal from one selected cycle to a successive selected cycle for producing a filtered signal which substantially follows said digital period signal, thereby substantially simultaneously tracking and filtering said IF signal.

27. A method according to claim 26 wherein the step of low pass filtering comprises digitally filtering, including storing a sample value of a given digital signal, and calculating said sample value in accordance with a predetermined transfer function comprising the sum of a first proportion of a previously stored sample value added to a second proportion of the present value of said digital signal.

28. A method according to claim 27 wherein the step of low pass filtering comprises the further step of periodically sampling said digital period signals, and converting each sampled digital period signal into a digital frequency-related signal to comprise said given digital signal prior to said calculating and storing.

29. A method according to claim 28 wherein the step of controlling the effective corner frequency comprises selecting said first and second proportions in accordance with variations in said digital frequency-related signal.