Software breakpoints with J-Link probe

RE: Software breakpoints with J-Link probe

Christopher — Wed, 25 May 2016 08:46:31 GMT

Yes, I posted a message on the Segger forum and I also opened an issue on the gnuarmeclipse Github repo. Thanks for your help !

RE: Software breakpoints with J-Link probe

RK — Wed, 25 May 2016 08:40:41 GMT

try the segger forums then because it seems none of the rest of us have this issue - they may have something to suggest.

RE: Software breakpoints with J-Link probe

Christopher — Wed, 25 May 2016 08:34:45 GMT

Thanks for your help @rols. With my setup, the processor is not stopped when I use your code.

JLinkARM.dll V5.12f
Target device nRF51822_xxAA
Firmware: J-Link Lite-Cortex-M V8
GNU ARM C/C++ J-Link Debugging version 3.2.1.201604190915
arm-none-eabi-gcc.exe (GNU Tools for ARM Embedded Processors) version 5.3.1 20160307

But it's working with the Segger tools version 5.10m.

RE: Software breakpoints with J-Link probe

RK — Wed, 25 May 2016 07:22:23 GMT

I really don't know what problem you're having but I can tell you this code works with GCC every time, including on the current JLINK version, I use it in my hardfault handler to toss me out to the debugger and I was using it today because .. it's been Hardfault Wednesday

.....

    volatile uint32_t __attribute__((unused)) pc_ret	= stacked_data[ 6 ];
    volatile uint32_t __attribute__((unused)) xPSR		= stacked_data[ 7 ];

	__BKPT(0);
}

RE: Software breakpoints with J-Link probe

Christopher — Wed, 25 May 2016 07:05:23 GMT

@hungbui the code above works with my Segger J-Link lite probe and the Segger tools 5.10m, but it's not working with the latest version V5.12 :(

I will post a message on the Segger forum, or I will contact the GNU ARM Ecplise plugin guys. Thanks for your help !

RE: Software breakpoints with J-Link probe

Christopher — Tue, 24 May 2016 17:15:09 GMT

They are no source in the Zip file you gave me... <locationURI>PARENT-3-PROJECT_LOC/main.c</locationURI> I try to make this working with the nRF51 and not the nRF52. There are some error callbacks in my code where it makes sense to stop the program automatically. This is a very developer-friendly way to debug a software. Could you tell me which version of the Segger tools you use ? I use the latest version available today, and this is maybe the problem...

RE: Software breakpoints with J-Link probe

Hung Bui — Tue, 24 May 2016 10:13:29 GMT

Hi Metch,

I attached here the project. It's basically the same with the blinky project provided by Vidar here.

armgccEclipse.zip

May I ask why you want to use the software breakpoint ?

RE: Software breakpoints with J-Link probe

Christopher — Tue, 24 May 2016 06:45:50 GMT

I cannot make this running correctly :( The processor does not halt on the software breakpoint. I program an .elf file instead of an .out file. This is the only difference I see. I use the maximum (-g3) debug level when compiling. Maybe do you use nay other debug flags ? Could you please give me some information about the tools and version use use ? Segger tools, Eclipse, GCC/GDB and debug probe ?

RE: Software breakpoints with J-Link probe

Hung Bui — Mon, 23 May 2016 13:27:29 GMT

@metch: no, no modification from default setting:

RE: Software breakpoints with J-Link probe

Christopher — Tue, 17 May 2016 07:22:35 GMT

@hungbui, thanks for you answer. It still doesn't work on my side... I use the SEGGER J-Link GDB Server V5.12e version, I will try with the same version as you.

Any custom settings in the "GDB client setup" and "Run/Restart Commands" ? I cannot see the configuration you use in the bottom of each images.

RE: Software breakpoints with J-Link probe

Hung Bui — Fri, 13 May 2016 14:16:00 GMT

Hi Metch,

here is the debugger and start up tab, I also tested with Jlink Lite and PCA10040 v0.9.0.

RE: Software breakpoints with J-Link probe

Christopher — Fri, 13 May 2016 07:14:02 GMT

SEGGER J-Link GDB Server V5.12e Command Line Version JLinkARM.dll V5.12e (DLL compiled Apr 29 2016 15:03:58)

Target device:                 nRF51822_xxAA
Target interface:              SWD
Target interface speed:        1000kHz

Connecting to J-Link...
J-Link is connected.
Firmware: J-Link Lite-Cortex-M V8 compiled Aug 20 2015 17:57:19
Hardware: V8.00
S/N: *****
Feature(s): GDB

RE: Software breakpoints with J-Link probe

Christopher — Fri, 13 May 2016 07:00:28 GMT

I also tested the same program using the onboard Segger probe on the nRF52 preview dev kit (PCA10040 version 0.9.0). Unfortunately, same result...

RE: Software breakpoints with J-Link probe

Christopher — Fri, 13 May 2016 06:50:24 GMT

@hungbui thanks for your reply. I use the latest Segger tools V5.12e, GNU ARM C/C++ J-Link Debugging 3.2.1.201604190915, GCC 5.3.1 20160307 and a Segger J-Link Lite probe with the latest firmware. The code compiles, but I still have the same message and no breakpoint in Eclipse...

Could you please post two screenshots of the GDB SEGGER J-Link Debugging configuration for the Debugger and Startup tabs ?

RE: Software breakpoints with J-Link probe

Hung Bui — Wed, 11 May 2016 13:43:50 GMT

@metch: yes, just tested, it worked for me here. Segger Jlink v5.10m, GNU ARM C/C++ J-Link Debugging 3.2.1.201604190915. I have to modified the code like this, so it compiles:

static inline void break_here(void)
   {
       __asm volatile(
           "bkpt #0x01\n\t"
           "mov pc, lr\n\t"
         );
   }

RE: Software breakpoints with J-Link probe

Christopher — Tue, 10 May 2016 07:51:55 GMT

@hungbui Have you tested you code with the Segger plugin from the GNU ARM Eclipse plugin ? Any help is welcome.

RE: Software breakpoints with J-Link probe

Christopher — Wed, 06 Apr 2016 15:41:07 GMT

I do more tests and the problem is a probably a wrong configuration or setup of the GNU ARM Eclipse plugin and the Segger J-Link debugger because my code works with Keil and with Eclipse + GDB + OpenOCD.

RE: Software breakpoints with J-Link probe

Hung Bui — Wed, 06 Apr 2016 11:16:22 GMT

I saw that you also posted a comment here. But what I understood is that the user who posted the thread managed to stop at the break point, but not able to continue, in your case it was that the debugger didn't stop.

RE: Software breakpoints with J-Link probe

Christopher — Wed, 06 Apr 2016 10:16:38 GMT

Thanks @hungbui. ; are missing in your code ;)

My problem is not a compilation issue. Is use the exact same code with the GNU GDB debugger and it works. With a J-Link Lite probe, I get the following messages:

Read 4 bytes @ address 0x00023544 (Data = 0x46F7BE01)
Starting target CPU...
Read 4 bytes @ address 0x00023544 (Data = 0x46F7BE01)
Starting target CPU...
[etc...]

The software breakpoint is not working with my setup unfortunately :(

Update 2016/05/25:

The following code can be used with GCC:

static inline void break_here(void) {
  __asm volatile(
    "bkpt #0x01\n\t"
    "mov pc, lr\n\t"
  );
}

This code only works with my Segger J-Link lite probe and the Segger tools 5.10m. It doesn't work with the the latest Segger version5.12...

Update 2016/07/08:

The error has been reported to Segger and they fix the problem. GDB 7.10 changed something in the way breakpoints halt execution, and current SEGGER JLinkGDBServer had problems to correctly inform GDB about the BKPT.

Software breakpoints work fine again from Segger tools version V5.12h. You should update the tools manually to the latest available version. You can download it from here: www.segger.com/.../jlink

RE: Software breakpoints with J-Link probe

Hung Bui — Wed, 06 Apr 2016 09:23:09 GMT

Hi metch, Yes my code is for KEIL. On GCC, I assume it should be:

 static inline void break_here(void)
    {
        __asm volatile(
            "bkpt #0x01"           
            "mov pc, lr"      
          );
    }

RE: Software breakpoints with J-Link probe

Christopher — Tue, 05 Apr 2016 18:11:24 GMT

Thanks @hungbui, unfortunately your code is not working with my setup. I will also try it with Keil. Maybe there is something wrong in my Eclipse / J-Link configuration. Any help is welcome.

RE: Software breakpoints with J-Link probe

Hung Bui — Tue, 05 Apr 2016 09:06:35 GMT

Hi metch, I haven't tested with GDB but testing on Keil show that Jlink worked fine. My function is like this:

__asm void break_here(void)
{
    bkpt #0x01
    mov pc, lr	
}