Motorola 700/800-Series User Manual

Page of 153
3-12
Debugger General Information
3
For this reason, abort is most appropriate when terminating a user 
program that is being debugged. Abort should be used to regain 
control if the program gets caught in a loop, etc. 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 is returned to the debugger. 
Break
A ÔÔpower-breakÕÕ is generated by pressing and releasing the 
<BREAK> key on the terminal keyboard. Break does not generate 
an interrupt. The only time break is recognized is when characters 
are sent or received by the console port. Break removes any 
breakpoints in your code and keeps the breakpoint table intact. 
Break also 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. 
Many times it may be desirable to terminate a debugger command 
before its completion Ñ during the display of a large block of 
memory, for example. Break allows you to terminate the command. 
SYSFAIL* Assertion/Negation
Upon entering 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