摘要 |
IN-PLACE DIAGNOSABLE ELECTRONIC CIRCUIT BOARD An on-board self diagnostic capability is realized in a circuit board with a microprocessor which is located on the circuit board and which interacts for diagnostic purposes with the functional circuitry on the board. The microprocessor interacts with an electrically erasable read-only-memory (EEROM) that is also located on the circuit board. Diagnostic signals occurring during the circuit board's normal operation are automatically detected and stored in the EEROM. Additionally, a control port at the circuit board permits activation in the microprocessor of diagnostic routines that accept input test data, apply test sequences to the functional circuitry and store the diagnostic results in the EEROM. Also, through control of the microprocessor, the EEROM is accessed to retrieve previously stored diagnostic results. |