Serial to Parallel Shift Register

To expand the I/O of a microcontroller, one can use a serial-in-parallel-out shift register to convert serial signals to a parallel output. Useful to control HD44780 type parallel LCD modules using only 3 wires (one for enable one, one for the shift register data, one for the shift register clock). The shift register would control the LCD in 4 bit mode with another bit for RS). http://www.allaboutcircuits.com/vol_4/chpt_12/4.html http://www.play-hookey.com/digital/shift-in_register.html