It's an Atmosic Atm3430e, which includes RF energy harvesting. So, I'm using 3 power sources depending on the application: Coin cell, USB, and RF, with a 1v8 net for sensors. Its power pin routing has some particulars that are poorly documented, and there are no publicly available reference designs. There are a few design docs which help, but leave open questions. So, I used LLMs to help me figure out which pins to connect to which. They did not seem capable of actually doing the work directly, but they answered my questions. We will see how correctly in a few weeks...

Also used LLMs to try to figure out how to flash/debug it. The setup I normally use (Tac-Connect ST-Link 6 pin + Probe-rs) won't work here; it's cortex-m, but their official guides indicate they want you do use a Segger J-Link, which I'm not ready to pay for at this point. It is a very expensive thing. So I'm going to try an NXP MCU-Link Pro. The St-Linkv3 I've been using will likely not work.