topic Why Kinetis K20 does not boot when disconnected from the debug probe? in CodeWarrior Development Tools

Why Kinetis K20 does not boot when disconnected from the debug probe?

adrianomitre — Fri, 29 Aug 2014 22:42:44 GMT

I am developing an application for the part MK20FX512VLQ12 using CodeWarrior 10.6 for MCU using as debug probes both P&E USB Multilink Universal and SEGGER J-Link. Its a very simple bareboard application (i.e., no RTOS), which uses Processor Expert for all drivers. Its binary takes less than 10 KB compiled with all debugging information on and all optimization off.

I can run the application in debug mode without problems. This is without breakpoints (except at the start of "main", which is unavoidable) to help with any timing or interaction issues. When I start a debug session, hit continue at the breaking point at the start of main() and only then disconnect the debug probe, it keeps running normally (as long as NMI is disabled, at least). When I choose Run (CTRL+F11) instead of Debug (F11), however, the application does not boot.

When measuring the RESET_b pin without the debug probe connected, it oscillates like described in PK60F120M Reset pin oscillating. This is after the application has been written to flash, though. I have even verified, when debugging, that memory positions 0x0 and 0x4 are properly set. I am, therefore, out of ideas.

Why the application does not boot when disconnected from the debug probe? How can I make it do?

Any help would be greatly appreciated.

Re: Why Kinetis K20 does not boot when disconnected from the debug probe?

Jorge_Gonzalez — Sat, 30 Aug 2014 02:43:00 GMT

Hello Adriano:

This is most likely to be caused by a hosted library. Check the next thread:

Re: MK10DX256VLK7 doesn't run standalone, just when debugging. Verified it's running from FLASH, not RAM.

PS. I suggest you to post always to a specialized forum space. Otherwise your threads get lost easily and nobody answers. E.g. this debugger question could fit in either of the next spaces:

CodeWarrior Development Tools

CodeWarrior for MCU

Regards!

Jorge Gonzalez

Re: Why Kinetis K20 does not boot when disconnected from the debug probe?

adrianomitre — Fri, 05 Sep 2014 22:27:57 GMT

Hello Jorge,

Thank you for your prompt and correct answer.

I would just like to suggest that more clear warnings be provided alongside de semi-hosting option regarding the fact that "the firmware will not boot when disconnected from the debugger and PC", given that the actual wording seems to be confusing for some developers (at the very least two :smileywink:).

Best regards,

Adriano Mitre