Total failure issues with nRF52840 mini

Development Boards MicroMod
1

Hi.

I have an issue with the 2 nRF52840 minis I ordered. I’ve soldered headers on both, and one, I can chalk up to user error even though I’m 80% sure there was a manufactured trace between VIN and GND. I cut said trace, but it had burnt out before I got to it in time.

The second one is more difficult. In the beginning, the boot drive came up just fine. I downloaded CircuitPython 6.2 and copied it over, then the problems began:

  1. Power LED is solid when plugged in.

  2. Boot drive only displays and pin 7 led blinks when:

a. I leave it unplugged for 5 minutes or so, plug it in, then double-click reset.

b. Only connects/displays drive/blinks for about 2 seconds before disconnecting/disappearing.

  1. Any other time its powered, nothing comes up in Device Manager nor a boot drive at all.

  2. I have tried factory reset, but with no luck.

Is there anything else to try/check for?

2

Hi Dave.

This hasn’t been tested with CircuitPython 6.2, there may be some incompatibilities. You might try going back to the version that’s in the hookup guide.

For the other board that has a short in it, sounds like there’s something wrong with your board.

If you purchased the board directly off our website, just [fill in the form on this page with your order number and the URL to this forum post and we can replace it for you.

If you purchased from a distributor or Amazon you will need to let them know you have a defective product and arrange with them for an exchange.](Return Policy - SparkFun Electronics)

3

Feel free to file an issue about the USB unreliability here: https://github.com/adafruit/circuitpyth … new/choose

I haven’t heard of major issues with nRF though.