METHOD AND APPARATUS FOR POWDER MANAGEMENT IN A MULTIFUNCTION CONTROLLER WITH AN EMBEDDED MICROPROCESSOR
 Inventors: Kenneth George Smalley, 10 Sandra
Dr., Hauppauge, N.Y. 11788; Ian
Fraser Harris, 5 Geoffrey La., Kings
Park, N.Y. 11754
 Appl. No.: 685,378
 Filed: Jul. 23, 1996
 Int. CI. G06F 1/32
 U.S. CI 395/750.04; 364/707; 395/556
 Field of Search 395/750, 750.04,
395/750.05, 556, 559; 364/707; 327/142
 References Cited
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5,222,239 6/1993 Rosch 395/750
5,339,446 8/1994 Yamasaki et al 395/750
5,369,771 11/1994 Gettel .
5,386,552 1/1995 Garney 395/575
5,446,906 8/1995 Kardach et al. .
5,560,020 9/1996 Nakatani et al 395/750
FOREIGN PATENT DOCUMENTS
0 419 908 A2 4/1991 European Pat. Off. . 0 446 958 A2 9/1991 European Pat. Off. . 0 474 963 A2 3/1992 European Pat. Off. .
0 499 178 Al 8/1992 European Pat. Off. .
0 708 398 A2 4/1996 European Pat. Off. .
Primary Examiner—Meng-Ai T. An
Assistant Examiner—Rupal D. Dharia
Attorney, Agent, or Firm—Proskauer Rose LLP
A method and apparatus for providing power management functions in a multifunction controller having an embedded microprocessor. An enter sleep mode indication is received in the microprocessor in the form of, for example, a command generated by a host central processing unit or an interrupt indicating a lack of system activity for a predetermined period of time. The clock input to the microprocessor is switched from a first clock source to a second clock source in response to the enter sleep mode indication. The main system supply may then be powered down by the microprocessor. The first clock source is then turned off after expiration of a first predetermined delay. The second clock is subsequently turned off after a second predetermined delay, to thereby place the system and the microprocessor into a sleep mode. While the system and microprocessor are in the sleep mode, an interrupt-handling portion of the microprocessor and a power control logic circuit remain powered off a low-current standby supply. Upon detection of a wake-up event, the second clock source is automatically started and applied to the microprocessor after a predetermined delay. The microprocessor can then process the wake-up event indicator, and if necessary power up the system and re-connect itself to the first clock source.
14 Claims, 6 Drawing Sheets