UNC4672A,V1英文说明,ABB模块
PPCBug包括显示和修改内存的命令，断点和跟踪功能，强大的汇编和反汇编程序用于修补程序，以及“通电自检”功能验证主CPU板的完整性。各种PPCBug例程处理输入/输出、数据转换和字符串函数的通过系统调用处理程序执行的程序。PPCBug由三部分组成部分：
❏ 命令驱动的用户交互软件调试器，也称为PPCBug。
❏ 一组命令驱动的诊断。”
❏ 接受系统控制台命令的用户界面航空站
UNC4672A,V1英文说明当使用PPCBug时，您可以从调试器中的任何一个进行操作目录（PPC1 Bug）或诊断目录（PPC1 Diag），其中告诉您当前目录由于PPCBug是命令驱动的，因此它在中执行各种操作对在键盘上输入的用户命令的响应。当您输入命令，PPCBug执行该命令，并再次出现提示。但是，如果您输入的命令导致执行用户目标代码（例如，GO），则控制可能返回或不返回到PPCBug，取决于用户程序的结果。控制流程PPCBug在PPCBug固件包用户手册中进行了描述，附录D中列出了相关文件。PPCBug类似于以前的摩托罗拉固件调试包（MVME147Bug、MVME167Bug、MVME187Bug），存在差异微处理器架构。这些主要反映在指令助记符、寄存器显示、的寻址模式汇编器/反汇编器，并将参数传递给系统调用。内存要求PPCBug总共需要768KB的读/写内存（例如，DRAM）。调试器从内存顶部分配此空间。对于例如，一个包含64MB（04000000美元）读/写内存的系统将PPCBug内存页放置在位置$03F80000到$03FFFFFF。实施
PPCBug主要用C编程语言编写，提供可移植性和可维护性的好处。必要时，组装语言以单独编译程序的形式使用仅包含汇编代码的模块。没有混合语言模块习惯于物理上，PPCBug包含在两个32针插口PLCC闪存中一起提供1MB存储的设备。可执行代码为每次通电或重置固件条目时的校验和，以及结果（包括闪存设备中包含的预计算校验和），根据预期校验和进行验证。
PPCBug includes commands for display and modification of memory,
breakpoint and tracing capabilities, a powerful assembler and disassembler
useful for patching programs, and a “self-test at power-up” feature which
verifies the integrity of the main CPU board. Various PPCBug routines
that handle I/O, data conversion, and string functions are available to user
programs through the System Call handler. PPCBug consists of three
parts:
❏ A command-driven user-interactive software debugger, also called
PPCBug.
❏ A set of command-driven diagnostics.”
❏ A user interface which accepts commands from the system console
terminal.
When using PPCBug, you operate from within either the debugger
directory (PPC1-Bug) or the diagnostic directory (PPC1-Diag) which
tells you the current directoryBecause PPCBug is command-driven, it performs its 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
(for instance, GO), then control may or may not return to PPCBug,
depending on the outcome of the user program. The flow of control in
PPCBug is described in the PPCBug Firmware Package User’s Manual,
listed in Appendix D, Related Documentation.
PPCBug is similar to previous Motorola firmware debugging packages
(MVME147Bug, MVME167Bug, MVME187Bug), with differences due
to microprocessor architectures. These are primarily reflected in the
instruction mnemonics, register displays, addressing modes of the
assembler/disassembler, and the passing of arguments to the system calls.
Memory Requirements
PPCBug requires a total of 768KB of read/write memory (for example,
DRAM). The debugger allocates this space from the top of memory. For
example, a system containing 64MB ($04000000) of read/write memory
will place the PPCBug memory page at locations $03F80000 to
$03FFFFFF.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.
Physically, PPCBug is contained in two socketed 32-pin PLCC Flash
devices that together provide 1MB of storage. The executable code is
checksummed at every power-on or reset firmware entry, and the result
(which includes a precalculated checksum contained in the Flash devices),
is verified against the expected checksum.
