@alexsh1 It turns out it does work. You just need to substitute much higher value resistors (e.g. 10M instead of 10K and use much higher values for the resistors in the voltage divider) so that under low light conditions the voltage measured on the unloaded solar panel doesn't show less than it should.

As pointed out by @reinhold, here's a handy tool for programming your nRF52840 dongle, and possibly other nRF52 projects too:

https://www.tindie.com/products/ElectronutLabs/pogoprog-model-c-pogo-pin-programmer-swd-2-pack/

I think I'd like it better if it could somehow latch itself to the board, though, so that I could also get debugging information hands free without having to continually press the tool up against the board.

What's the smallest hole ptich that I can do pogo pins with? e.g. is 1.27mm pitch possible?

@uhrheber said in nRF5 action!:

@neverdie There are three ways to manipulate registers directly from Micropython:

1. Use machine.mem16

2. Use the decorator @micropython_viper
   The Viper code emitter implements integer types and pointers, allowing to access memory and registers directly.

3. Use the decorator @micropython.asm_thumb
   Write your code in ARM assembler.

Problem: I don't know whether any of this is already implemented and works reliably in Micropython for nRF.

Thanks! We finally nailed it all the way down on this thread here: https://forum.micropython.org/viewtopic.php?f=12&t=5377

@uhrheber said in Everything nRF52840:

One interesting thing I stumbled upon:

https://github.com/insane-adding-machines/unicore-mx

UniCore-MX | Universal Core for ARM Cortex-M0/0+/3/4/7/X

Supports nRF51/52

I looked at the link, but I can't figure out what problem it's solving. What's the headline on that?

@scalz hinted at it previously, but it looks like MyNewt OS might offer yet another way to do OTA updates. According to their posted information, it offers:

A open-source Bluetooth 5.0 stack (both Host & Controller), NimBLE, that completely replaces the proprietary SoftDevice on Nordic chipsets. (https://github.com/apache/mynewt-core/blob/master/README.md)

Apparentlly it runs on both the nRF52832 and the nRF52840.

@nc78 Earlier you had asked about vendors for the dongle. I found an alternative dongle that ships from China:
https://www.tindie.com/products/Zelin/nrf52840-micro-dev-kit-usb-dongle/
Price is very similar. I like it better than the Nordic dongle, because it exposes pins P0.06 and P0.08, which are used by the DK for UART communications.

@toyman Micropython on the BBC micro:bit (which uses the nRF51822) has a Radio library that uses Nordic's proprietary radio modes and doesn't involve Bluetooth. I suppose the question is: what would be involved in getting it to run on the nRF52832 or the nRF52840. Seems like it would be substantially the same.

Faiing that, if I can directly manipulate the radio registers from miropython as I can from C, then it shouldn't be too hard to get at least minimal radio capability up and running from within micropython.

If I can get rudimentary radio communications working in micropython, then from there it should be easy to do OTA updates via REPL. I did some proof of concept to that effect on the micro:bit, but quickly ran out of memory--the micro:bit has only a total of 16K of RAM, so there's very little headroom to begin with. On the nRF52840, lack of RAM shouldn't be an issue.

@redferne Thanks for your post. How are you liking PlatformIO? Does PlatformIO have full support, with all the extra pin names etc., for the nRF52840?

@toyman OTA updates.