nRF Connect couldn't find the device of nRF52811 with a custom board?

RE: nRF Connect couldn't find the device of nRF52811 with a custom board?

Stian Røed Hafskjold — Mon, 12 Aug 2019 11:18:54 GMT

If the board can't run the precompiled hex files the issue has to be hardware related, since the hex files are known to work on the chip.

Start with the blinky example in the SDK (examples\peripheral\blinky) and see if this is working. Then start the HF crystal and see if it's running. Then start the LFXO and see what happens. The RTC example is a good starting point for this (examples\peripheral\rtc).

When debugging, start with a break point in the top of main, and continue down the list. Check the return value and see if they all return with NRF_SUCCESS. If not you might get a hint on what is wrong by checking the return value.

RE: nRF Connect couldn't find the device of nRF52811 with a custom board?

DragonEmperor — Fri, 02 Aug 2019 09:01:06 GMT

Reply 1: After checking the Tooling for custom nRF52811 PCB based on ARM-GCC and PCA10040, I thought there might be something wrong with the external LF oscillator. So I want to use LF RC to rule out the external LF oscillator failure possibility.

But at the very beginning, I just left sdk_config.h default config. After the same procedure, there wasn't any bluetooth device named "Nordic" in nRF Connect App either. And I'v checked the pcbdoc again, the board has two external crystal referring to the official nrf52811_qcaa_dcdc design.

Reply 2: I couldn't locate the problem. But I could deploy SDK_DIR\examples\ble_peripheral\ble_app_uart\pca10040\s132\arm5_no_packs\ble_app_uart_pca10040_s132.uvprojx to my custom nRF52832 board.

Reply 3: I tried to flash SDK_DIR\examples\ble_peripheral\ble_app_uart\hex\ble_app_uart_pca10056e_s112.hex and SDK_DIR\examples\ble_peripheral\ble_app_beacon\hex\ble_app_beacon_pca10056e_s112.hex, both don't work.

Reply 4: When debugging, the code falls on NRF_BREAKPOINT_COND in app_error_fault_handler(). It seems that the program couldn't debug with BLE program.

Reply 5: Could you please explain the wrong way in detail?

RE: nRF Connect couldn't find the device of nRF52811 with a custom board?

Stian Røed Hafskjold — Thu, 01 Aug 2019 11:54:59 GMT

1. I see that you have a 32KHz crystal in your design, so why do you want to use LF RC? If you configure the project to use LFRC you must also set correct settings for the calibration interval: https://devzone.nordicsemi.com/f/nordic-q-a/45610/how-to-change-ble_app_uart-example-to-work-without-lfclk/179519#179519

2. Are you able to figure out if the problem lies with the firmware or the custom hardware? Can you flash the firmware on a development board you know is working.

3. Can you try to flash any of the precompiled hex files in the SDK to see if they work?

4. Can debug the firmware to see if it's actually able to initialize the softdevice and start advertising? Use the debugging tool in the IDE you are using and check for any asserts.

5. A common mistake is to solder the HF crystal the wrong way.