So much speculation here. Let me set the record straight(er). (I worked in Tesla FW, left 5 years ago.) Tesla does use industry best practices. All code mus

So much speculation here. Let me set the record straight(er). (I worked in Tesla FW, left 5 years ago.) Tesla does use industry best practices. All code must pass MISRA checkers, code is modular, and reused when possible. We used all sorts of chips (that were auto qual) of many different architectures. We had extensive tools for e.g. stack monitoring, diagnostic readouts, and much more. If you move from, say, one ST ARM chip to another one in a similar family, the peripherals may be a little different, but generally work the same way (with maybe a few more or fewer features). So reworking the I/O drivers is work, but given the excellent layering of Tesla "body control" FW, it's really quite straightforward to pick a different processor from a given family. It's for sure true that if you went from ST ARM to Freescale/NXP ARM the peripherals are diff, so yes, more time would be needed to write the I/O drivers. But the effort ongoing when I left was exactly to make the appropriate SW generalizations so it would be possible to do exactly this.