nRF5340 Programming Issue

RE: nRF5340 Programming Issue

LL01 — Wed, 29 Oct 2025 09:47:10 GMT

Thank you all for your help. I finally determined that the issue was caused by setting the DCDC to a specific power mode, which prevented the board from operating normally. While the MCU was unable to respond, I shorted DCED to 3.3V and reconfigured the settings to resolve the problem. In future circuit designs, it will be modified to operate in DCDC mode.

RE: nRF5340 Programming Issue

LL01 — Wed, 29 Oct 2025 08:49:27 GMT

Thank you for the reminder. I did connect the reset wire to the debugging interface through soldering, but there was still no response.

RE: nRF5340 Programming Issue

Turbo J — Wed, 29 Oct 2025 08:40:45 GMT

If you bothered to read the product specifications, the "recovery" procedure has tight timing requirements on the reset line. Hence it needs to be connected to the debugger itself.

RE: nRF5340 Programming Issue

LL01 — Wed, 29 Oct 2025 08:33:31 GMT

Thank you for your suggestion. I just tried removing the pull-up resistor from the reset line and performed erase operations, but the MCU still did not respond. Then, I re-soldered the pull-up resistor and repeated the operations, yet the MCU remained unresponsive. All three circuit boards I have on hand are experiencing the same issue—they worked fine during the initial connection, allowing programming and operations, but subsequently stopped functioning.

RE: nRF5340 Programming Issue

Turbo J — Wed, 29 Oct 2025 08:07:23 GMT

You need to have the reset line connected to the debugger in order to be able to "recover" the device. Picture looks like you missed that.

Most debuggers have the Vtarget line configured as voltage input by default in order to be able to accept a wide range of targets with different levels.