MVME5100 Single Board Computer Programmer's Reference Guide

Exceptions
Sources of Reset
Soft Reset
CPU Reset
Exceptions
There are five potential reset sources on the MVME5100 series. They are
as follows:
1. Power-On Reset
2. RESET Switch
3. Watchdog Timer Reset
4. Software generated Module Reset using MODRST Bit Register.
5. Reset generated from system bus
Each source of reset will result in a reset of the processor, Hawk ASIC, and
all other on-board logic. The PMC RESETOUT_L pin will also be
activated by all reset sources except for the PMC PCI RST# input.
Software can assert the SRESET# pin of the processor by appropriately
programming the P0 bit in the Processor Init Register of the Hawk MPIC.
The Hawk SRST1_L output is connected to the CPU reset logic. Setting
the P1 bit in the Hawk Processor Init register will result in the local
processor being held in reset. Clearing the P1 bit will release the reset. This
feature can be used by a processor on the host board to disable the local
processor while the host processor programs the Bank A on-board
FLASH.
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