Abort Switch (S1) - Motorola MVME1603 Installation And Use Manual

Functional Description

ABORT Switch (S1)

The switch is located on the LED mezzanine. When activated by
ABORT
software, the switch can generate an interrupt signal from the base
ABORT
3
board to the processor at a user-programmable level. The interrupt is
normally used to abort program execution and return control to the
PPCBug debugger firmware located in the MVME1603/1604 EPROM
and Flash memory. The interrupt signal reaches the processor module via
∗
ISA bus interrupt line IRQ8 . The signal is also available at pin PB7 of the
Z8536 CIO device, which handles various status signals, serial I/O lines,
and counters.
The interrupter connected to the switch is an edge-sensitive circuit,
ABORT
filtered to remove switch bounce.
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