Electronics - Keil - Errors using uVision4 MDK-Lite

In this tutorial we will see errors discovered by playing with the IDE uVision4 MDK-Lite.

Of course detailed errors and solutions are provided and will be added if more errors would be found.

Simple and easy, so let's get started.

Unknow target connected

If, when you tried to download code to flash memory, you encountered this error:

Unknow target connected

from the Debugger - Cortex-M Error popup.

And just after a new popup saying:

Error: Flash Download failed - Target DLL has been cancelled

Then let's see how to resolve it.

Open your uVision4 MDK-Lite and go to > Flash > Configure Flash Tools... > Utilities > Use Target Driver for Flash Programming > Select ST-Link Debugger > Settings > Debug > Port > SW > Click OK.

Error: Flash Download Failed - "Cortex-M3" or "Cortex-M4"

In the Build Output you have:

No Algorithm found for: 08000000H - 08000733H

To remove this error, let's say to uVsion4 where is our programming algorithm:

Open the IDE then > Flash > Configure Flash Tools... > Utilities > Settings > Flash Download > Programming Algorithm > Click the Add button > Select your processor flash > Add > OK.

*** error 57: illegal address (0x08000000)

Once clicked on Start/Stop Debug Session, several popups ST-LINKIII-KEIL appear with the successive following messages:

Unknown target connected
Flash programming error
Error while attempting to write 1844 bytes to 0x08000000
Unknown target connected

And finally in the Command window we have this error:

*** error 57: illegal address (0x08000000)

To resolve it, go out from the debugger and then click Flash > Configure Flash Tools... > Debug > On the right side, select Use ST-Link (be careful to not select the ST-Link Deprecated version) > Settings > Debug > Port > SW > OK > OK.


A great place to be. heart



Thank you! This post helped me.


Wow ... after 2 hours, I finally found this perfect article !
You saved my life :)


Thank you!


Thanks a lot for these tips. Really help me a lot. Keep the great job.


Thanks so much!


Thank you, the solution for 'Unknown target connected' helped me out :-)


Thanks a lot it works flawlessly


Thanks a lot!


Thanks a ton, saved my day.


No target connected show in keil U vision?

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