Error 0x00030806 - how to recover

when the E2lite loses communication with the processor, next time I try to debug it gives this error:

”First communications with the Target MCU cannot be made normally. DAP cannot be found in the connection target. Check the target or lower the SWD clock frequency.”

What is the best way to get it working again, without having to power down the probe, the target, shut down E2Studio and restart the computer?

  • My experience has been that the e2lite must be power-cycled to recover.  The better question for you might be, what is causing this issue to occur?

  • That sometimes works, but more often than not it doesn't. Sometimes power cycling the E2lite AND the target will fix it, but sometimes it remains until the computer is rebooted.

    To answer your question: Lack of EMC immunity in the E2lite is causing it to occur. If a large contactor changes state nearby, the target is rock solid, but the E2lite gets lost.

  • The debugger is not designed for high electro-magnetic type of environments.

    You might consider a longer ribbon cable for the debugger to get away from the problem area, although cannot go too long before signal integrity issues become a problem (you have not mentioned the device nor the debug interface type so advice is limited).

    You could try shielding the debugger with a tin shield this would not have to be anything too fancy but a simple metal cover may be enough to protect it.