The optoelectronic transceiver includes first and second controller ICs. Each controller IC includes logic, a memory, an interface, and at least one input port. Each memory is configured to store digital diagnostic data and has a unique serial device address to allow a host access to each of these controller...http://www.google.com/patents/US7149430?utm_source=gb-gplus-sharePatent US7149430 - Optoelectronic transceiver having dual access to onboard diagnostics
