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Computer Group Literature Center Web Site
Startup and Operation
2
Abort
Aborts are invoked by pressing and releasing the ABORT switch on the
MVME167P front panel. When you invoke an abort while executing a user
program (running target code), a snapshot of the processor state is stored
in the target registers. This characteristic makes aborts most appropriate
for terminating user programs that are being debugged.
If a program gets caught in a loop, for instance, aborts should be used to
regain control. The target PC, register contents, etc., help to pinpoint the
malfunction.
Pressing and releasing the ABORT switch generates a local board
condition which may interrupt the processor if enabled. The target
registers, reflecting the machine state at the time the ABORT switch was
pressed, are displayed on the screen. Any breakpoints installed in your
code are removed and the breakpoint table remains intact. Control returns
to the debugger.
Break
Pressing and releasing the <Break> key on the terminal keyboard
generates a ‘‘power break’’. Breaks do not produce interrupts. The only
time that breaks are recognized is while characters are being sent or
received by the console port. A break removes any breakpoints in your
code and keeps the breakpoint table intact. If the function was entered
using SYSCALL, Break also takes a snapshot of the machine state. This
machine state is then accessible to you for diagnostic purposes.
In many cases, you may wish to terminate a debugger command before its
completion (for example, during the display of a large block of memory).
Break allows you to terminate the command.
Diagnostic Facilities
The 167Bug package includes a set of hardware diagnostics for testing and
troubleshooting the MVME167P. To use the diagnostics, switch directories
to the diagnostic directory.
