Motorola MVME172 - Manual (Page 230)

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MC2 Chip
3
RESET Switch Control Register
The RESET switch on the MVME172 front panel and several status and
control bits are defined by this register.
RSWE The RESET switch enable bit is used with the ‘‘no
VMEbus interface’’ option. This bit is duplicated at the
same bit position in the VMEchip2 at location
$FFF40060. When this bit is high, or the duplicate bit in
the VMEchip2 is high, the
RESET switch is enabled.
When both bits are low, the RESET switch is disabled.
BDFLO When this bit is high, the MC2 chip asserts the BRDFAIL
signal pin. This signal is wired-or to the VMEchip2 board
fail pin. It controls the board fail (
FAIL ) LED on the
MVME172.
CPURS When this bit is set high, the power-up reset status bit is
cleared. This bit is always read zero.
PURS This bit is set by a power-up reset. It is cleared by a write
to the CPURS bit.
BRFLI When this status bit is high, the BRDFAIL signal pin on
the MC2 chip is asserted. When this status bit is low, the
BRDFAIL signal pin on the MC2 chip is not asserted. The
BRDFAIL pin may be asserted by an external device, the
BDFLO bit in this register, or a watchdog time-out.
ADR/SIZ $FFF42044 (8 bits)
BIT 31 30 29 28 27 26 25 24
NAME BRFLI PURS CPURS BDFLO RSWE
OPER R R R R R C R/W R/W
RESET 0 0 0 1 PL 1 P 0 1 PL 1 P