Self-Test for a Keyboard/Display Unit
Original Publication Date: 1986-Jul-01
Included in the Prior Art Database: 2005-Mar-09
A detached keyboard/display unit has a self-test sequence in which keys on the keyboard are each tested separately, display commands on the display are tested, an audible feedback is tested, and an Intel 8051 microprocessor, which controls the keyboard/display unit, is tested. In a self-test mode, the Intel 8051 microprocessor polls the keyboard with key breaks being discarded as can be observed from the flow chart. The test uses all of the hardware (keyboard, display, and beeper) in the same fashion as in normal system operation. If the test works at all, this provides verification that the microprocessor is functioning normally. If the "pip" (beeper) is heard, this verifies that the audible feedback is functioning normally. This is found in the first portion on the left side of the flow chart prior to the self-test mode.