Keil Can Erase nRF51822 but not Program?

[Nick]

I find this strange but I can program the HRM demo fine but with my own code it compiles with no errors or warnings but will not program with Error: Flash Download failed - "Cortex-M0".

The funny thing is after getting that error i can still erase the chip which means it is detected:

[i]JLink info:

DLL: V4.72 , compiled Jun 12 2013 15:47:08 Firmware: J-Link OB-SAM3U128 V1 compiled Feb 5 2013 15:27:51 Hardware: V1.00 S/N : 480203173

• 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: nRF51822_xxAA 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

Full Chip Erase Done.[/i]

Is my project set up wrong? I copied the HRM code and have been modifying it to create a new service.

Thanks everyone!

[Håkon Alseth]

Hi,

Most likely your device has gone into deep sleep mode. In this mode the debugger interface is detached, meaning you will not be able to program it properly (known issue with the current HW revision). Usually, if you unplug the USB and then program it after plugging it in again, it will be active.

If that does not work, use nrfjprog.exe to recover your device (will erase softdevice as well): nrfjprog --recover -s

This sequence can be done through the nRFgo Studio GUI tool as well.