Force Computers SPARC CPU-54, Reference Manual

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Controls, Indicators, and Connectors Front Panel of the SPARC/CPU-54
SPARC/CPU-54 3 - 5
Keys
The front panel of the SPARC/CPU-54 provides two mechanical keys
and a hexadecimal rotary switch (front panel shows MODE).
Reset
When enabled and toggled, it instantaneously affects the CPU board by
generating a push-button Power On Reset (POR) to the UltraSPARC-IIe.
Push-button Power On Reset has the same effect as a Power On Reset
from the power supply, with the only difference, that the corresponding
status bit (B_POR) in the UltraSPARC-IIe Reset_Control Register is set
and the DRAM refresh is not influenced.
Abort
When enabled and toggled, it instantaneously affects the CPU board by
generating a push-button external initiated reset (XIR). Push-button
external initiated reset allows a user-reset (abort) of part of the proces-
sor without resetting the whole system. UltraSPARC-IIe sets the B_XIR
bit in the Reset_Control Register when a push-button external initiated
reset is detected.
Mode
The mode key is a hexadecimal rotary switch which is decoded with
4 bit. Its functions are user-defined. The default setting is F
16
.