RE: Unable to Flash Custom Board MDBT53 using NRF5340 DK

Kazi Afroza Sultana — Thu, 28 Aug 2025 10:23:35 GMT

Hello,

Did you try to add the following configurations to disable the DC/DC as you don't have it on your board?

CONFIG_BOARD_ENABLE_DCDC_NET=n
CONFIG_BOARD_ENABLE_DCDC_HV=n
CONFIG_BOARD_ENABLE_DCDC_APP=n

Then program the application again and recover both app and core by nrfjprog.

Or You can try to power the internal regulator internally. If DCDC inductors are missing, externally power the relevant DEC pins to bring the chip out of reset, then immediately recover/flash firmware that disables DCDC. You can read this previous case (workaround explanation).

RE: Unable to Flash Custom Board MDBT53 using NRF5340 DK

umer — Fri, 22 Aug 2025 15:26:58 GMT

Yes, it is the same 3.3 V.

Recover nrf5340 (MDBT53) custom board

From the above link, I have found that I was missing the right configuration settings for disabling the DC/DC mode of operation. As a result, the device is "bricked" and not detected anymore.

Is there any recovery from this state?

RE: Unable to Flash Custom Board MDBT53 using NRF5340 DK

Kazi Afroza Sultana — Fri, 22 Aug 2025 11:28:32 GMT

Hello,

The error seems that debug port can not be connected on your custom board. Most likely the insufficient VDD prevent the custom board to access debug port. Have you measured that the voltage is supplied t custom board is as same as DK?

RE: Unable to Flash Custom Board MDBT53 using NRF5340 DK

umer — Thu, 21 Aug 2025 16:20:32 GMT

Update:

I have been able to flash it once successfully using the nRF Desktop Connect Programmer app. However, for any later attempts, I get the message in the application as given above (and provided here). This is my output when I "Read" the device after "Erase & Write" operation:

11:17:09.050	Recovering Application core
11:17:09.051	Recovering Application core 0%
11:17:10.381	Recovering Application core 100%
11:17:10.381	Recovering Application core completed
11:17:10.381	Recovering Network core
11:17:10.383	Recovering Network core 0%
11:17:12.020	Recovering Network core 100%
11:17:12.020	Recovering Network core completed
11:17:12.020	Loading core information for Application core
11:17:12.023	Update files regions according to Application core
11:17:12.023	Parse memory regions for file
11:17:12.023	Update files regions according to Network core
11:17:12.023	Parse memory regions for file
11:17:12.025	Loading core information for Application core 0%
11:17:12.025	Loading core information for Application core 100%
11:17:12.026	Loading core information for Application core completed
11:17:12.026	Loading core information for Network core
11:17:12.026	Loading core information for Network core 0%
11:17:12.026	Loading core information for Network core 100%
11:17:12.027	Loading core information for Network core completed
11:17:12.029	Update files regions according to Application core
11:17:12.029	Parse memory regions for file
11:17:12.029	Update files regions according to Network core
11:17:12.029	Parse memory regions for file
11:17:12.645	Writing HEX to Application core
11:17:12.716	Writing HEX to Application core 0%
11:17:13.285	Writing HEX to Application core 50%
11:17:13.285	Writing HEX to Application core 50%
11:17:13.458	Writing HEX to Application core 75%
11:17:13.458	Writing HEX to Application core 100%
11:17:13.469	Writing HEX to Application core completed
11:17:14.438	Error: Failed with exit code 1. One or more device info tasks failed: * 802001162: Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled (Generic) Message: Operation device-info failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled.
11:17:14.443	Update files regions according to Application core
11:17:14.443	Parse memory regions for file
11:17:15.098	Reading readback protection status for Application core
11:17:15.099	Reading readback protection status for Application core 0%
11:17:15.261	Failed "reading readback protection status for application core". Error: code: 1, description: Generic, message: Batch task protection-get failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled
11:17:15.277	Error: Failed with exit code 1. One or more batch tasks failed: * 802001162: Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled (Generic) Message: Batch task protection-get failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled.
11:17:31.323	Error: Failed with exit code 1. One or more device info tasks failed: * 802001162: Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled (Generic) Message: Operation device-info failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled.
11:17:31.952	Reading readback protection status for Application core
11:17:31.953	Reading readback protection status for Application core 0%
11:17:32.099	Failed "reading readback protection status for application core". Error: code: 1, description: Generic, message: Batch task protection-get failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled
11:17:32.125	Error: Failed with exit code 1. One or more batch tasks failed: * 802001162: Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled (Generic) Message: Batch task protection-get failed, Device error: Setting the debug port SELECT register failed while powering up sys and debug regions (Unknown Error in J-Link DLL (error code =-1)). This might indicate that the debug port is unavailable. Please double-check device power supply and SWD lines, and that SWD isn't disabled.

RE: Unable to Flash Custom Board nrf5340 dk

umer — Thu, 21 Aug 2025 09:14:33 GMT

Update:

1. Moreover, in the custom board design, care has been taken in connecting VDD and VDDH together for DC/DC operation. Here are the screenshots from the circuit schematic:

2. My custom device does not have an explicitly identified VDD pin. I am using an IC test-clip to bring VDD from the output of the voltage regulator to the SWD connector P20. See the schematic here:

However, this does not help. I still see the same errors on nRF Desktop Programmer application.

One other thing I have tried:

- I have tried providing voltage supply from the nRF5340 dev kit following the guidelines here. I again use the IC test-clip to take the voltage VDD to the voltage regulator output.

Is there a fundamental reason why this method would not work?