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ARM: Starting Fast Models debug session fails with flash error

Information in this knowledgebase article applies to:

  • MDK-ARM version 4.70 to 5.14


I followed the instructions in the manual to configure a debug session using the Fast Models debug driver for µVision. However, starting a debug session to simulate my program will result in an error like this:

No Algorithm found for: 00000000H - 00000D7BH
Erase skipped!
Error: Flash Download failed  -  "Cortex-M4"


In the Flash Download configuration of the project target the option Update Target before Debugging is enabled. This causes the unnecessarily enabled flash function in the Fast Models debug driver (DbgFM.dll) to be utilized at start of a debug session when the project was changed in some way. This then of course fails, as for Fast Models debugging, flash download is not required/possible.


Disable the Update Target before Debugging option in the Flash Download Configuration.

In future versions of MDK-ARM the Fast Models debug driver (DbgFM.dll) will have the flash download functions completely disabled. "Update Target before Debugging" will then have no effect any more and so also eliminates the problem.


Last Reviewed: Thursday, April 30, 2015

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