user manual

Debugger General Information
B-10
B
SYSFAIL* Assertion/Negation
Upon a reset/power-up condition the debugger asserts the
VMEbus SYSFAIL* line (refer to the VMEbus specification).
SYSFAIL* stays asserted if any of the following has occurred:
❏ Confidence test failure
❏ NVRAM checksum error
❏ NVRAM low battery condition
❏ Local memory configuration status
❏ Self test (if system mode) has completed with error
❏ MPU clock speed calculation failure
After debugger initialization is done and none of the above
situations have occurred, the SYSFAIL* line is negated. This
indicates to the user or VMEbus masters the state of the debugger.
In a multi-computer configuration, other VMEbus masters could
view the pertinent control and status registers to determine which
CPU is asserting SYSFAIL*. SYSFAIL* assertion/negation is also
affected by the ENV command.
MPU Clock Speed Calculation
The clock speed of the microprocessor is calculated and checked
against a user definable parameter housed in NVRAM (refer to the
CNFG command in the Commands Table). If the check fails, a
warning message displays. The calculated clock speed is also
checked against known clock speeds and tolerances.