Post by thread:9600 bauds at 4Mhz

Have someone here made half-duplex async communications at 9600 bauds with PIC16C84, 4Mhz? AN555 from microchip doesn't seem to works at this baud rate and clock frequency. Julio

If the processor you used is anything like the 16c54 for serial communications you have two problems. First, the 5volt RS232 expects an RS232 converter to raise the signal to 12 volts AND to INVERT it. However, not only are the 5volt signals upsidedown, but I also needed to alter the clock constants by more than I would have expected by the change I made in clock frequencies. I would recomend a quick look with an oscilloscope is called for here. Good luck. Gordon spam_OUTG.J.FlanaganTakeThisOuTncl.ac.uk Tel. 0191 222 8261 Fax. 0191 222 6442 Department of Medical Physics, Medical School, Newcastle upon Tyne NE2 4HH.