Unable to Get BLE Advertising or GPIO Blink on Custom ISC-nRF52832-A PCB

[Chinmay Mulgund]

I’m developing on a custom PCB that carries the ISC-nRF52832-A (nRF52832) and a BMA400 sensor. I can successfully flash the chip over SWD using an ST-Link v2 (connected to VCC, SWDIO, SWCLK, GND) but I cannot get any basic functionality to work—neither BLE advertising nor even a simple LED blink on a GPIO. Below are the details of what I’ve tried and the observed behavior:

Board & Toolchain

• Custom PCB with ISC-nRF52832-A

• SWD header pins: VCC (3.3 V), SWDIO, SWCLK, GND
• ST-Link v2 as uploader/debugger (configured to 3.3 V target)

            Platform: Windows 10, Arduino IDE & PlatformIO (NordicnRF52 platform 10.9.0, Arduino core for Adafruit nRF52)



Verify Log:

Sketch uses 2100 bytes (0%) of program storage space. Maximum is 409600 bytes.
Open On-Chip Debugger 0.10.0-dev-00254-g696fc0a (2016-04-10)
debug_level: 0
0x4000
adapter speed: 10000 kHz
target halted due to debug-request
** Programming Started **
wrote 4096 bytes from file …/nrfBluetooth.ino.hex in 0.156s (25.6 KiB/s)
** Programming Finished **
** Verify Started **
verified 2220 bytes in 0.047s (46.2 KiB/s)
** Verified OK **
** Resetting Target **
shutdown command invoked

Flash and verify always succeed, but no visible behavior on the board.

Looking forward to your guidance.

[Asbjørn]

Hello Chinmay,

With custom boards behaving this way there's a couple of things I'd start by checking.

Q1: Do you have an external 32k crystal on your board? If not, have you defined to not use LFXO, but LFRC instead?

Q2: Do you have the components for the DCDC  on you board? If not, have you made sure you're not configuring to use it?

Q3: Are you able to run code in debug mode or with RTT enabled, is the program counter moving and are you seeing any print on the uart/RTT?

Best regards

Asbjørn