**JLink Warning: CPU could not be halted

RE: **JLink Warning: CPU could not be halted

Paul — Thu, 22 Oct 2015 15:46:51 GMT

Hi Hung, I found the problem: a hardware bug. I feel bad that it was just wasting your valuable time.

RE: **JLink Warning: CPU could not be halted

Hung Bui — Thu, 22 Oct 2015 15:35:45 GMT

Hi Paul,

From your description, it worked with the example ? If it only happens on your application, you may want to send us the project so we can test here.

RE: **JLink Warning: CPU could not be halted

Paul — Thu, 22 Oct 2015 15:30:54 GMT

Sorry, found that problem. It was a hardware bug: This is a battery backed up system. I used to debug with battery in the circuit, so no problem. Then I took the battery away without thinking it will cause any issues. But today I found out without battery in the system, a DC/DC circuit controlled by software is generating enough noise to reset the CPU when software is trying to turn it on. Battery was a big capacitor to absorb the "kick".

Anyway, good new. It solved debug problem, and more importantly exposed a hardware issue.

RE: **JLink Warning: CPU could not be halted

Paul — Thu, 22 Oct 2015 15:03:14 GMT

Screen shot for ble_app_hrs_s110 is attached in the original post

RE: **JLink Warning: CPU could not be halted

Hung Bui — Thu, 22 Oct 2015 11:18:49 GMT

Hi Paul,

Could you try with one of our example, the ble_app_hrs for example. And take a screenshot when you trying to debug ?

RE: **JLink Warning: CPU could not be halted

Paul — Wed, 21 Oct 2015 22:18:57 GMT

Recreated the project, still the same issue.

RE: **JLink Warning: CPU could not be halted

Paul — Wed, 21 Oct 2015 20:56:37 GMT

I tried new firmware but same result. Yes, other projects are working with SDKV9 on my computer. I am going to create a new project to try.

RE: **JLink Warning: CPU could not be halted

Paul — Wed, 21 Oct 2015 20:55:20 GMT

JLink info:

DLL: V5.02f, compiled Oct 2 2015 20:51:34 Firmware: J-Link Lite-Cortex-M V8 compiled Aug 20 2015 17:57:19 Hardware: V8.00 S/N : 538001129 Feature(s) : GDB

RE: **JLink Warning: CPU could not be halted

Hung Bui — Tue, 15 Sep 2015 07:38:46 GMT

@Paul: How did you do the upgrade ? Do you have the same problem when testing with the SDK v9 examples ? Could you try to upgrade the Jlink driver to v5.0 ?

RE: **JLink Warning: CPU could not be halted

Paul — Mon, 14 Sep 2015 15:12:47 GMT

It is KEIL, and Level 0 (-O0).

RE: **JLink Warning: CPU could not be halted

Hung Bui — Mon, 14 Sep 2015 09:00:24 GMT

Hi Paul,

Could you let me know which debugger are you using? Was it KEIL or GDB ?

Have you made sure you changed the optimization level to 0 instead of 3 as in default configuration in C/C++ tab in project setting? Optimization compiling compresses the code and won't allow the debugger to halt the CPU correctly.