JTAG Programmer (under $100, not a DK)

[rshankle]

Hi Folks,

We have 6 factories that will be programming custom boards that use the nRF52832.  I'm one of the software developers and have been using a dev kit to program and debug the boards.

We want to now create a commissioner for the board and want to use something more "factory ready" for programming the boards via the JTAG port other than a development kit.

I've looked at: https://www.segger.com/products/debug-probes/j-link/models/model-overview/   And all the options seem to be an order of magnitude more expensive than the DK.  (Except for the education units which are off limits to us since we don't qualify.)

Has anyone found a programmer that is under $100?  Seems silly that there isn't one available.  (The factory workers don't need debug capability.)

thanks,

Bob

[koniho]

The Black Magic Probe is an opensource programmer than can be used to program nrf52 series chips.

https://github.com/blacksphere/blackmagic/wiki

We have successfully used a design based on the black magic probe to program nrf52832's in production.

[rshankle]

Thanks!  I'll check it out.

Bob

[Mojo]

This one http://embeddedsoftdev.blogspot.com/p/idap-link.html comes with software for nRF5x series flashing.  Supports parallel flashing multi-boards, flashing Softdevice + App + DFU, Flashing using SDCard.  It can also protect/unprotect the nRF5x.

[rshankle]

thanks,

Bob

[wpaul]

I use the Olimex ARM-USB-OCD-H debugger, with the ARM-JTAG-SWD adapter and ARM-JTAG-20-10 cable, in conjunction with OpenOCD. The debugger costs about $60 and the adapters are ~$5 each. You should be able to find all 3 here:

https://www.mouser.com/Search/Refine?Keyword=Olimex+ARM-USB-OCD-H

This assumes you expect to use the same kind of mini 10-pin header that they use on the DK board (which seems to be fairly common for ARM JTAG/SWD programming). The Olimex uses a fairly common FTDI chip. I don't know off the top of my head what IDE/debugger software packages it's compatible with so you should check that (for me OpenOCD is enough).

If you want to go cheaper still, you should also be able to use the ST-Micro ST-Link V2 debugger:

https://www.mouser.com/ProductDetail/STMicroelectronics/ST-LINK-V2?qs=sGAEpiMZZMsUcx5t7XFI3RIxq36q1BfC

However I'm not sure if it comes with the right 10-pin cable. I think you may be able to use the ARM-JTAG-20-10 adapter from Olimex if it doesn't. This is an SWD-only debugger: it doesn't speak ARM JTAG, so you can't use it to debug larger ARM CPUs (e.g. Cortex-A).

And if you want to go even cheaper still, there are some ST-Link V2 knockoffs:

https://www.mouser.com/ProductDetail/Adafruit/2548?qs=sGAEpiMZZMsMSm715rCt%252BlkZLiRrWII%2FiCGPHRoC5wqL0U52rt%252BD9Q%3D%3D

NOTE: The ST-Link V2 and its clones have one drawback, which is that they can only communicate with the standard ARM DAP. They can't be used to access the Nordic CTRL-AP port, which is where the magic "mass-erase recovery" register is located. This means if you lock your devices by setting the APPROTECT register in the NVMC, you will not be able to recover the chip using the ST-Link V2 debuggers. The Olimex is a low-level debugger and can be used to perform CTRL-AP mass erase. I wrote down how to do it here:

https://github.com/netik/dc27_badge/blob/master/hardware/programming/debug.txt

-Bill