RE: Panasonic PAN1780 RoadTest: digging deeper and comparing evaluation kits

parasquid — Fri, 20 Nov 2020 14:43:00 GMT

I'm really quite surprised at how difficult it is to understand how to evaluate high voltage mode on the PAN1780, and try out that configuration without accidentally frying the module. High voltage mode is a headline feature of the nRF52840 and the nRF52840DK even has a three-way toggle switch to showcase that yes, you can power the module directly from a fully charged ay 4v2 LiPo battery.

Just a few comments on the NFC pins: according to the infocenter https://infocenter.nordicsemi.com/topic/ug_nrf52840_dk/UG/nrf52840_DK/hw_nfc_if.html they can be used as GPIO pins if configured via the UICR and they are configured as NFC by default. I'm don't have much experience with RF but I'm not sure why the NFC portion don't have space for compensating caps to tune the antenna--maybe because the eval board is not supposed to be used for production anyway so there's no point to tuning?

I did try out the j-link on the PAN1780 for programming a bare nRF52 chip here https://www.element14.com/community/groups/roadtest/blog/2020/09/27/road-testing-the-pan1780-evaluation-kit-part-1#jive_… and I agree that the absence of the other pins constrains me to using only SWD. Then again like you mentioned, Panasonic Industry probably didn't pay for an official "debug out" license https://www.segger.com/products/debug-probes/j-link/models/j-link-ob/#debug-out-option

Debug Out option

J-Link OB is designed to debug the target device.
Using it to debug a device that is on another board, or to build debug probes (stand-alone J-Links), is not permitted under the standard license.
However, there is a debug out option, available for an additional charge, which allows using the J-Link OB to program and debug custom hardware.

I wish I had your document when I was doing my roadtest; there were a few projects I had to scrap because I had difficulty understanding how things were connected.