Motorola M68EVB912B32, User Manual

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OPERATION
68EVB912B32UM/D 3-7
When operating in POD mode, the D-Bug12 RESET or STOP command can be used to regain
control of the target system.
3.5 USING D-BUG12 COMMANDS
D-Bug12, the EVB’s firmware-resident monitor program, provides a self-contained operating
environment that allows writing, evaluation, and debugging of user programs.
3.5.1 Command-Line Prompt
D-Bug12 displays one of three command-line prompts, depending upon its operating mode
and/or the state of the target system. When D-Bug12 is operating in the EVB mode, it displays
the single character "
>
" at the beginning of a line when it is waiting for the user to enter a
command. When a command is issued that causes user code to run, D-Bug12 places the terminal
cursor on a blank line, where it remains until control returns to D-Bug12.
When operating in the POD mode, D-Bug12 displays one of two prompts, depending upon the
state of the attached target system. When the target system is in active background mode (not
running a user program), the two-character prompt
"S>"
is displayed, indicating that the target is
stopped and not running a user program. When the target system is running a user program, the
two-character prompt "
R>
" is displayed, indicating that the target is running a user program.
Because the M68HC12 Background Debug Mode interface allows the reading and writing of
target system memory even when the target is running a user’s program, the probe
microcontroller is always available for the entry of commands. D-Bug12 commands that
examine or modify target system memory may be issued when either the "
S>
" or "
R>
" prompt is
displayed.
3.5.2 Entering Commands
Commands are typed on the terminal’s D-Bug12 prompt line and executed when the carriage-
return (ENTER) key is pressed. D-Bug12 then displays either the appropriate response to the
command or an error indication.
The D-Bug12 command-line prompt is the greater-than sign (>). Type the command and any
other required or optional fields immediately after the prompt, as follows:
command-line syntax:
<command> [<parameter>] ...[<parameter>]<ENTER>
where:
<
command
> is the command mnemonic.