In the 2 batch, we got 20 faulty CPUs, we tried the X-ray of a Paris hackerspace mate who works in a hospital:

...it didn't help much but my heatgun became my best friend:

Berfore changing it a few tests were performed:

Made in BlackLoop (Paris Hackerspace).

The microcontroller was not arduino compatible at the time this project started. The 1st tests were made with a $10 dev boards and a $10 JTAG programmer, using open source tools only:

https://github.com/honnet/twi