bill, thanks for posting that. i have begun to study it. but i have the sinking feeling that, after soldering it all together, my product will be bigger than a NANO, tho cheaper.
Not sure what you are thinking about with a 2 wire implementation buta two wire implementation, just like a 3 wire implementationnever has to block interrupts as there are no time critical sections or bitsthat have to be protected since there are no rc filters involved whenusing 2 or 3 wires to run a shift register.
geoff, when you do get a chance to hook it up, i am interested to know what you found.