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MON51 is a debug monitor for 8051 user programs. It consists of:

  • A configurable monitor program that resides and runs on your target system.
  • The µVision Debugger and its associated MON51 driver.

The code space requirements of MON51 are small. It can run from about 5K of external or on-chip CODE memory. It requires only 256 bytes of von Neumann memory for monitor variables and storage.

To debug programs with MON51, you must configure the monitor for your specific target system (which has several requirements). Then, you must alter the load/starting address of your target program and download it to the monitor using µVision.


  • µVision allows you to create multiple target configurations for a single project-one of which could be used for the debug monitor project settings.
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