miniPCI POST Code Display
post5a - PC Engines Gmbh (PC Engines)
miniPCI format to fit WRAP boards and most modern notebook PCs. During power on self-test (POST), most PC BIOSes will write diagnostic codes to port 80h or port 84h (auto select, whichever is written first). Use post5a to display these codes on a dual digit LED display. Additional LEDs indicate the status of the power supply rails.