3

MC2 Chip

RESET Switch Control Register

The RESET switch on the MVME172 front panel and several status and control bits are defined by this register.

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

 

 

 

 

 

 

 

 

 

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.

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Image 230
Motorola MVME172 manual Reset Switch Control Register