Summary

While the reset code is technically challenging, it doesnt need to be intimidating. Your initial draft can be quite simple and should be. As Ive stressed before, in these early stages, its essential that you take baby steps. The modular structure of the code facilitates an incremental approach. Your first implementation of the start up code should be as primitive as possible. Leave exceptions disabled and stub all the exception handlers with simple traps. Leave the cache and memory management unit in their default, disabled state. Leave all other peripherals, except your communication device, disabled. Use only the simplest communication channel you can preferably a serial port. Once you get a command prompt from this primitive implementation, then you can pursue more elaborate versions. Again, the modular structure of MicroMonitor helps by suggesting a natural sequence for these revisions.

If you are careful to take small steps, implementing only as much as absolutely necessary at each step, then you should find that building the monitor is a relatively straight-forward process.



Embedded Systems Firmware Demystified
Embedded Systems Firmware Demystified (With CD-ROM)
ISBN: 1578200997
EAN: 2147483647
Year: 2002
Pages: 118
Authors: Ed Sutter

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