Hi all, I have recently added some 'bit banging' transmitter code to my web site. There is also code to initialise the internal usart on the 16CXX series. Both routines use a crystal of 3.6864 Mhz but they can be adapted for other speeds. If you do use this crystal speed, make sure you use the XT setting on your oscilator and not the HS setting. www3.mistral.co.uk/brian.clewer/ Regards, Brian.