user manual

4-12
Debugger General Information
4
Break Sequence
1. Removes any breakpoints in your code and keeps the
breakpoint table intact.
2. Takes a snapshot of the machine state if the function was
entered using SYSCALL. This machine state is then accessible
to you for diagnostic purposes.
SYSFAIL* Assertion/Negation
Upon a reset/powerup 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. Refer to Appendix A.
MPU Clock Speed Calculation
The clock speed of the microprocessor is calculated and checked
against a user definable parameter contained in NVRAM (refer to
the CNFG command in Appendix A). If the check fails, a warning
message is displayed.