Motorola MVME177, Installation And Use Manual

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Using the 177Bug Debugger
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Using the 177Bug Debugger
Entering Debugger Command Lines
177Bug is command-driven and performs its various operations in
response to user commands entered at the keyboard. When the
debugger prompt (
177-Bug>
) appears on the terminal screen, then
the debugger is ready to accept commands.
As the command line is entered, it is stored in an internal buffer.
Execution begins only after the carriage return is entered, so that
you can correct entry errors, if necessary, using the control
characters described in Chapter 3.
When you enter a command, the debugger executes the command
and the prompt reappears. However, if the command entered
causes execution of user target code, for example
GO , then control
may or may not return to the debugger, depending on what the
user program does. For example, if a breakpoint has been specified,
then control returns to the debugger when the breakpoint is
encountered during execution of the user program. Alternately, the
user program could return to the debugger by means of the TRAP
#15 function Ò.RETURNÓ.
In general, a debugger command is made up of the following parts:
a. The command identifier (i.e., MD or md for the Memory
Display command). Note that either upper- or lowercase is
allowed.
b. A port number if the command is set up to work with
more than one port.
c. At least one intervening space before the first argument.
d. Any required arguments, as specified by command.
e. An option Þeld, set off by a semicolon ( ; ) to specify
conditions other than the default conditions of the
command.