FBM230 P0926GU扩展模块，FOXBORO使用进展
内存要求172Bug的程序部分大约有512KB的代码，由下载、调试器和诊断包组成，包含完全在闪存或PROM中。172Bug从地址$FF800000执行，无论是在闪存还是EPROM。如果拆下J21针脚9和10处的跳线，则地址空间的闪存和EPROM交换。适用于MVME172-2xx系列板（MVME172LX），工厂发货配置带有跳线J21针脚9-10已删除（172Bug在EPROM中运行）。
FBM230 P0926GU扩展模块172Bug初始堆栈完全改变了8KB的SRAM内存，atDRAM可以是ECC或奇偶校验类型。DRAM夹层映射在连续从零开始（00000000美元），第一大。有两个相同大小但不同类型的夹层，映射奇偶校验DRAM到选定的基址，ECC夹层将跟随。如果两者都有夹层为ECC型，底层为第一层。172Bug需要2KB的NVRAM来存储电路板配置，通信和引导参数。该存储区始于$FFFC16F8，结束于$FFFC1EF7。172Bug需要至少64KB的连续读/写内存运转ENV命令控制内存块的位置位于。无论板载RAM位于何处，前64KB用于172Bug堆栈和静态变量空间，其余保留作为用户空间。无论何时重置MVME172LX，目标PC都会初始化为对应于用户空间开头的地址，目标堆栈指针初始化为用户内的地址空间，目标中断堆栈指针（ISP）设置为用户的顶部空间在通电或重置时，SRAM基址的地址偏移量$C000是命令驱动的；它执行各种操作以响应在键盘上输入的命令。当172 Bug>提示时出现在终端屏幕上，调试器已准备好接受调试器命令。当屏幕上出现172 Diag>提示时，将显示调试器已准备好接受诊断命令。要从一种模式切换到另一种模式，请输入SD（切换目录）。到检查当前所在目录中的命令，使用帮助命令（HE）。您输入的内容存储在内部缓冲区中。只有在输入回车。这允许您更正输入错误，如果必要时，使用调试包中描述的控制字符摩托罗拉68K CISC CPU用户手册，第1章。
Memory Requirements
The program portion of 172Bug is approximately 512KB of code,
consisting of download, debugger, and diagnostic packages and contained
entirely in Flash memory or PROM.
The 172Bug executes from address $FF800000 whether in Flash or
EPROM. If you remove the jumper at J21 pins 9 and 10, the address spaces
of the Flash and EPROM are swapped. For MVME172-2xx series boards
(MVME172LX), the factory ship configuration is with jumper J21 pins 9-
10 removed (172Bug operating out of EPROM).
The 172Bug initial stack completely changes 8KB of SRAM memory atDRAM can be ECC or parity type. DRAM mezzanines are mapped in
contiguously starting at zero ($00000000), largest first. With two
mezzanines of the same size but different types, parity DRAM is mapped
to the selected base address and the ECC mezzanine will follow. If both
mezzanines are ECC type, the bottom one is first.
The 172Bug requires 2KB of NVRAM for storage of board configuration,
communication, and booting parameters. This storage area begins at
$FFFC16F8 and ends at $FFFC1EF7.
172Bug requires a minimum of 64KB of contiguous read/write memory to
operate. The ENV command controls where this block of memory is
located. Regardless of where the onboard RAM is located, the first 64KB
is used for 172Bug stack and static variable space and the rest is reserved
as user space. Whenever the MVME172LX is reset, the target PC is
initialized to the address corresponding to the beginning of the user space,
and the target stack pointers are initialized to addresses within the user
space, with the target Interrupt Stack Pointer (ISP) set to the top of the user
space.
address offset $C000 from the SRAM base address, at power-up or reset172Bug is command-driven; it performs its various operations in response
to commands that you enter at the keyboard. When the 172-Bug> prompt
appears on the terminal screen, the debugger is ready to accept debugger
commands. When the 172-Diag> prompt appears on the screen, the
debugger is ready to accept diagnostics commands.
To switch from one mode to the other, enter SD (Switch Directories). To
examine the commands in the directory that you are currently in, use the
Help command (HE).
What you key in is stored in an internal buffer. Execution begins only after
the carriage return is entered. This allows you to correct entry errors, if
necessary, with the control characters described in the Debugging Package
for Motorola 68K CISC CPUs User’s Manual, Chapter 1.
