nRF51422 flashes ok, but debugging fails: stays in MOVES R0,R0

[henning larsen]

We have a custom board with nFR51422. Of the first 4 prototypes only one works correctly. This indicates that the PCB is ok. One difference is the chip marking. The working is nrf51422 QFAACO 1319AK and non working ones are all nrf51422 QFAACO 1306AD.

The non-working ones are partly functional in the sense: The flash programming works and verifies without reported problems and the Keil programmer finalizes programming with the message: application running. I can see that neither of the xtal clocks are starting.

Debugging in Keil fails: When breaking into the debugger R15(PC) is FFFFFFFE and the instructions are all MOVS R0,R0 all the way down. PC counter increments but stays doing MOVS R0,R0 instructions.

Breakpoint in arm_startup_nrf51.s in reset handler is never taken.

What could leave flash programming working but execution failing?

Any hints on what could be a possible reason are warmly received.

[Hung Bui]

Hi Henning,

We have some issue with the batch 1306AD. Our QA will contact you shortly for the replacement.

[Cadambi]

Hi , I am having the nrf51422 Evaluation kit and i am trying to run the blinky project. The chip marking is n51422 QFAACO 1302AC. The build works fine and here is the build message :

Build target 'nrf51422' creating preprocessor file for main.c... compiling main.c... linking... Program Size: Code=488 RO-data=208 RW-data=0 ZI-data=4192
"._build\blinky_arm.axf" - 0 Error(s), 0 Warning(s).

But when i try to load it from Keil ARM , the 'LED 3' blinks. Could you please tell me why it blinks and what changes needed to be made to make the LED 0 and LED 1 to blink as per the example blinky project?

Here is the output from Keil after i try to execute the 'Load' :

Load "C:\keil\ARM\Device\Nordic\nrf51422\Board\pca10003\blinky_example\arm\_build\blinky_arm.AXF" Set JLink Project File to "C:\keil\ARM\Device\Nordic\nrf51422\Board\pca10003\blinky_example\arm\JLinkSettings.ini"

• JLink Info: Device "CORTEX-M0" selected (0 KB flash, 0 KB RAM).

JLink info:

DLL: V4.74b, compiled Aug 19 2013 23:26:44 Firmware: J-Link OB-SAM3U128 V1 compiled Feb 5 2013 15:27:51 Hardware: V1.00 S/N :

• JLink Info: Found SWD-DP with ID 0x0BB11477
• JLink Info: FPUnit: 4 code (BP) slots and 0 literal slots
• JLink Info: Found Cortex-M0 r0p0, Little endian. ROMTableAddr = 0xE00FF003

Target info:

Device: Cortex-M0 VTarget = 3.300V State of Pins: TCK: 0, TDI: 0, TDO: 1, TMS: 1, TRES: 1, TRST: 1 Hardware-Breakpoints: 4 Software-Breakpoints: 8192 Watchpoints: 2 JTAG speed: 1000 kHz

Erase Done. Programming Done. Verify OK. Application running ...

Note: Please refer the attachment for debugging error

Debugging error.doc

[Hung Bui]

Hi Cadambi,

Have you make sure the debug option was configured properly ? Please follow the setting in the attached image.

Regarding blinky example, did you mean LD3 (not LED3 ? ) was blinking when you program ? Did it blink after programming, when the device is running ?

Have you tried any other examples ?

debugOption.PNG

debugOption.PNG