I have nrf51422 dk. The boards I connect to 3.3V power and via jlink to my pc. I use the JLink command line tool. I can not access the chips. Erasing is not possible and reading register gives nonsense values. It looks that the Jlink identifies a chip 0x0BB11477 but reading the register is somehow not possible.
I have custom hardware where this works out of the box.
Is there a "debug enable" command? Why does my custom hardware works and the DK boards deny to communicate via jlink? I assume I do not need to write to special hardware address when using the "erase" command.
Regards, Adib
Below is my jlink log.
C:\Users\taraben.a>jlink
C:\Users\taraben.a>"c:\Program Files (x86)\Segger\JLinkARM_V484a\jlink.exe" SEGGER J-Link Commander V4.84a ('?' for help) Compiled Apr 4 2014 18:02:34 DLL version V4.84a, compiled Apr 4 2014 18:02:19 Firmware: J-Link Lite-Cortex-M V8 compiled Aug 29 2012 15:24:23 Hardware: V8.00 S/N: 538000974 Feature(s): GDB VTarget = 3.267V Info: Could not measure total IR len. TDO is constant high. Info: Could not measure total IR len. TDO is constant high. No devices found on JTAG chain. Trying to find device on SWD. Info: Found SWD-DP with ID 0x0BB11477 Info: Found Cortex-M0 r0p0, Little endian. Info: FPUnit: 4 code (BP) slots and 0 literal slots Cortex-M0 identified. Target interface speed: 100 kHz J-Link>h
WARNING: T-bit of XPSR is 0 but should be 1. Changed to 1. PC = FFFFFFFE, CycleCnt = 00000000 R0 = FFFFFFFF, R1 = FFFFFFFF, R2 = FFFFFFFF, R3 = FFFFFFFF R4 = FFFFFFFF, R5 = FFFFFFFF, R6 = FFFFFFFF, R7 = FFFFFFFF R8 = FFFFFFFF, R9 = FFFFFFFF, R10= FFFFFFFF, R11= FFFFFFFF R12= FFFFFFFF SP(R13)= FFFFFFE0, MSP= FFFFFFE0, PSP= FFFFFFFC, R14(LR) = FFFFFFF9 XPSR = C1000003: APSR = NZcvq, EPSR = 01000000, IPSR = 003 (HardFault) CFBP = 00000000, CONTROL = 00, FAULTMASK = 00, BASEPRI = 00, PRIMASK = 00 J-Link>device 51422 Info: Device "NRF51422_XXAA" selected (257 KB flash, 16 KB RAM). Reconnecting to target... Info: Found SWD-DP with ID 0x0BB11477 Info: Found Cortex-M0 r0p0, Little endian. Info: FPUnit: 4 code (BP) slots and 0 literal slots J-Link>h PC = FFFFFFFE, CycleCnt = 00000000 R0 = FFFFFFFF, R1 = FFFFFFFF, R2 = FFFFFFFF, R3 = FFFFFFFF R4 = FFFFFFFF, R5 = FFFFFFFF, R6 = FFFFFFFF, R7 = FFFFFFFF R8 = FFFFFFFF, R9 = FFFFFFFF, R10= FFFFFFFF, R11= FFFFFFFF R12= FFFFFFFF SP(R13)= FFFFFFE0, MSP= FFFFFFE0, PSP= FFFFFFFC, R14(LR) = FFFFFFF9 XPSR = C1000003: APSR = NZcvq, EPSR = 01000000, IPSR = 003 (HardFault) CFBP = 00000000, CONTROL = 00, FAULTMASK = 00, BASEPRI = 00, PRIMASK = 00 J-Link>erase Erasing device (nRF51422_xxAA)... Info: J-Link: Flash download: Flash programming performed for 1 range (262144 by tes)
****** Error: Verification failed @ address 0x00000000 Info: J-Link: Flash download: Total time needed: 38.769s (Prepare: 0.733s, Compa re: 20.354s, Erase: 4.550s, Program: 0.000s, Verify: 10.041s, Restore: 3.089s) Erasing done.
