Motorola PrPMC800/800ET Processor PMC Module User Manual

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PrPMC800/800ET Processor PMC Module Installation and Use (PrPMC800A/IH5)
 5 PPCBug
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PPCBug includes commands for:
Display and modification of memory
Breakpoint and tracing capabilities
A powerful assembler and disassembler useful for patching programs
A self-test at power-up feature which verifies the integrity of the system
PPCBug consists of three parts:
A command-driven, user-interactive software debugger, described in the PPCBug 
Firmware Package User’s Manual. It is hereafter referred to as “the debugger” or 
“PPCBug”.
A command-driven diagnostics package for the PrPMC800/800ET hardware, hereafter 
referred to as “the diagnostics.” The diagnostics package is described in the PPCBug 
Diagnostics Manual.
user interface or debug/diagnostics monitor that accepts commands from the system 
console terminal.
When using PPCBug, you operate out of either the debugger directory or the diagnostic 
directory.
If you are in the debugger directory, the debugger prompt
PPC7-Bug>
 is displayed and all of the debugger commands are available.
If you are in the diagnostic directory, the diagnostic prompt
 
PPC7-Diag> 
is displayed and all of the diagnostic commands are available, as well as 
all of the debugger commands.
Because PPCBug is command-driven, it performs various operations in response to user 
commands entered at the keyboard. When you enter a command, PPCBug executes the 
command and the prompt reappears. However, if you enter a command that causes execution 
of user target code (e.g., GO), control may or may not return to PPCBug, depending on the 
outcome of the user program.
Memory Requirements
PPCBug requires a maximum of 768KB of read/write memory (DRAM). The debugger allocates 
this space from the top of memory. For example, a system containing 64MB ($04000000) of 
read/write memory places the PPCBug memory page at locations $03F40000 to $03FFFFFF.
PPCBug Implementation
PPCBug is written largely in the C programming language, providing benefits of portability and 
maintainability. Where necessary, assembly language has been used in the form of separately 
compiled program modules containing only assembler code. No mixed-language modules are 
used.