Testing the soft-uart receiver on an ATtiny24

It seems to work. Now I only have to make the rest of the code live with it in peace. That doesn't work 100% right now. The LED driver interrupt gets upset sometimes.

The entry points of the pin-change ISR are marked with double-pulses, sampling the data is marked by single pulses. Spikes 2-9: sampling the data byte, spike 1: start bit, spike 10: stop bit, spike 11: hmmmm ?!?