Using PPCBug
Implementation and Memory Requirements
PPCBug is written largely in the C programming language, providing |
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benefits of portability and maintainability. Where necessary, assembly |
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language has been used in the form of separately compiled program | ||
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modules containing only assembler code. |
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Physically, PPCBug is contained in two socketed |
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devices that together provide 1MB of storage. The executable code is |
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checksummed at every |
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(which includes a precalculated checksum contained in the flash devices), |
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is verified against the expected checksum. |
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PPCBug requires a maximum of 768KB of read/write memory. The |
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debugger allocates this space from the top of memory. For example, a |
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system containing 64MB (0x04000000) of read/write memory will place |
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the PPCBug memory locations 0x03F40000 to 0x3FFFFFF. Additionally, |
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the first 1MB of DRAM is reserved for the exception vector table and |
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stack. |
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Using PPCBug
PPCBug is
What you enter is stored in an internal buffer. Execution begins only after you press the Return or Enter key. This allows you to correct entry errors, if necessary, with the control characters described in the PPCBug Firmware Package User’s Manual, listed in Appendix C, Related Documentation.
After the debugger executes the command, the prompt reappears. However, depending on what the user program does, if the command causes execution of a user target code (that is, GO), then control may or may not return to the debugger.
http://www.motorola.com/computer/literature |