Motorola MPC564EVB, User Manual

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3-12 MPC564EVB User’s Manual
Commands
BR Breakpoints
Usage: BR addr <-r> <-c count> <-t trigger>
The BR command inserts or removes software breakpoints at address addr. The value for addr may
be an absolute address specified as a hexadecimal value, or a symbol name. Count and trigger are
numbers converted according to the user-defined radix, normally hexadecimal.
If no argument is provided to the BR command, a listing of all defined breakpoints is displayed.
The -r option to the BR command removes a breakpoint defined at address addr. If no address is
specified in conjunction with the -r option, then all breakpoints are removed.
Each time a breakpoint is encountered during the execution of target code, its count value is
incremented by one. By default, the initial count value for a breakpoint is zero, but the -c option
allows setting the initial count for the breakpoint.
Each time a breakpoint is encountered during the execution of target code, the count value is
compared against the trigger value. If the count value is equal to or greater than the trigger value,
a breakpoint is encountered and control returned to dBUG. By default, the initial trigger value for
a breakpoint is one, but the -t option allows setting the initial trigger for the breakpoint.
If no address is specified in conjunction with the -c or -t options, then all breakpoints are initialized
to the values specified by the -c or -t option.
Examples:
To set a breakpoint at the C function main() (symbol _main; see “symbol” command), the
command is:
br _main
When the target code is executed and the processor reaches main(), control will be returned to
dBUG.
To set a breakpoint at the C function bench() and set its trigger value to 3, the command is:
br _bench -t 3
When the target code is executed, the processor must attempt to execute the function bench() a third
time before returning control back to dBUG.
To remove all breakpoints, the command is:
br -r