Intermittent Disconnects When Flashing UF2 Firmware to Tenstar nRF52840 Pro Micro Board

[sasith_ind]

I am experiencing an issue with my Tenstar nRF52840 Pro Micro board, which utilizes the Adafruit UF2 bootloader. When attempting to flash new firmware by copying a .uf2 file to the device, the board intermittently disconnects before the transfer completes. This behavior occurs regardless of the method used: dragging and dropping the file, using the west flash command, or manually copying the file.

Steps to Reproduce:

1. Enter bootloader mode by grounditwiceng RST pin 

2. The board appears as a mass storage device named NICENANO.

3. Attempt to copy a .uf2 firmware file (e.g., zephyr.uf2) to the drive.

4. The device disconnects before the transfer completes.

Tried updating the bootloader but still same issue persists. 

[Hung Bui]

Hi Sasith, 

I would suggest to try asking on Adafruit support as we at Nordic are not so familiar with the Adafruit ecosystem. 

Other members of devzone may be able to jump in to help though. 

[sasith_ind]

Ok I will thanks for the help