I am using Cortex M0 in Designstart FPGA with the Arty A35 and DAPlink board with Keil.
But on loading the Demo software I get the following message box:
After Rest Target it works.
The same issue arises if I set a breakpoint or remove one.
I played with several settings in the Keil debug dialog but it didn't help.
This happens also on the reference Cortex M0 bit file.
Is that a known limitation or is something wrong with my DAPLInk board.
I do not think that the board is defect.
I can program the FPGA with my own Cortex M0 synthesised bit-files.
I can also download the M0 software in Keil and start the debugger.
Debugging in Keil works but behaves a bit strange.
I think the problem is either the M0 Coresight or the DAPLink board.
I will check if CortexM3 Designstart shows the same behaviour.
did you swap out USB cables? Try debugging with a lower core clock? Those might fix intermittent communication issues
If only one particular project has this issue, did you look at "t MDK message usually means the device is asleep, has locked up, or there is some sort of issue with the pins meant for JTAG communication (pins using alternate function, clocking turned off, etc.)"