Nobody has seen any such slave in the wild, yet. In the very unlikely
case that someone actually sees or needs this, patches are welcome
though (together with sample .sr files).
##
# TODO: Look into arbitration, collision detection, clock synchronisation, etc.
-# TODO: Implement support for 10bit slave addresses.
# TODO: Implement support for inverting SDA/SCL levels (0->1 and 1->0).
# TODO: Implement support for detecting various bus errors.