| 摘要 |
<p>PURPOSE:To output a fixed signal when abnormality occurs in a system by providing a control circuit to output the content of a latch when the latch which sets the output state of a port and a counter overflow when the abnormality occurs in the system. CONSTITUTION:When a terminal 16 is used as an output port, an output level when the abnormality is detected in the system is set on the terminal, and the output level when the abnormality occurs is written on the latch 19. When the system is operated abnormally, an interruption signal 8 becomes active by the overflow of the counter 1, and simultaneously, a control signal 15 becomes inactive and a control signal 20 becomes active, then, the content of the latch 19 is outputted from the terminal 16. Thereby, it is possible to output an arbitrary level from hardware by setting the output level when the abnormality occurs in the system on the latch 19 when a microprocessor is initialized.</p> |
