Hi,
Just received a nRF52840 connected it to my Apple Silicon Macbook (maybe relevant?) which is running Sequoia 15.2 via a USB-C to micro cable.
When I powered it up, the NeoPixel LED was shifting colors and all seemed fine. Then I tried to flash it. CircuitPython pre-built (10.0.3). I put it in bootloader mode (the NeoPixel went green, and the folder showed up on my desktop). I tried to copy the UF2 file into it, and it immediately went red, dropped the folder, and didn't reset. Just got stuck like that.
So, I tried building the sample blinky and flashing that. Same. Then, hours of building, flashing, checking for serial ports, etc.
At some point, I read that I might need an updated bootloader, so I pulled down the 0.9.2 file and dropped THAT in the folder. Lo and behold, it seemed to work. At least, when I look at the INFO_UF2.TXT file, it says:
UF2 Bootloader 0.9.2 lib/nrfx (v2.0.0) lib/tinyusb (0.12.0-145-g9775e7691) lib/uf2 (remotes/origin/configupdate-9-gadbb8c7)
Model: Adafruit Feather nRF52840 Express
Board-ID: nRF52840-Feather-revE
Date: Jul 19 2024
SoftDevice: not found
(It was originally 0.8.3)
So, I tried flashing those packages again. No dice. Always the same thing... goes into bootloader mode, seems great, but as soon as I try to copy (or drag and drop or dd), the big LED turns red and the folder drops. Tried several different cables.
I'm starting to think it's just a hardware problem in the flash or something. Does this ring a bell with anyone? Anything else I can try? At this point, it's either in bootloader mode and appears to be fine (USB serial port shows up, folder mounts, LEDs green) or it's in busted mode-- red big LED, flickering yellow and pulsing red by the USB connector.
Happy to provide any additional information.
