[pslam]

The specific case I was thinking of was the host suffering an incident where it is not possible or practical for its software to know where it left off.

For example, you get a kernel panic, or soft-reset for some reason. When you recover, you now have a bus in an unknown state, possibly mid-transaction, and if you pick the wrong order in which to bring the bus back to idle, you might wedge it or accidentally cause a side-effect (e.g overwrite a byte in an EEPROM).

[amelius]

But doing bus communication from software is generally a bad idea. Best is to use a hardware controller dedicated to the task. Do you have examples for bus protocols that can be run from software?