Be careful about temps / cooling! Especially when you start attempting sending those chips commands. Don't want them to starting and immediately going up in flames. But Skot knows much more than myself about this (how / when they start hashing / getting hot).

It's just that I've experienced (as a customer) finished mining products hashing even when not getting supplied any data at all (not sure what they were doing - again: as a customer).
Just saying I've encountered it and I'm not sure whether that was just the 'idle behavior' of those chips (older stuff, not BM1397 for sure) or firmware-related.