On Mon, Apr 7, 2008 at 2:49 PM, Bob Axtell wrote: > Ivan Petrushev wrote: > > Oh, so I forgot the [PIC] tag... > > On topic: I will change BRGH = 1 and SPBRG = 12. Anything else? I'm > > runing on internal RC oscilator on 4MHz, so the baud rate will be 19.2 > > kbps. Actually the speed isn't important, recieving something is > > important. I'm running both devices with the same OSCON and baud rate > > settings. > > > > > Despite the Microchip advertising to the contrary, I have never been > able to get the Int RC Osc > to handle RS232 with any degree of reliability. The reason is that the > RC timing "wobbles"; at > one time it is below speed, next time it is above speed. To make it > work even SOME, the baud > rates must be reduced to 1200baud or slower, so the wobble is no longer > noticeable. I've had no trouble getting reliable comms at 115200 baud with the 16F688 (internal oscillator at 8 MHz) Maybe the higher rate helps. This is a sample size of a few dozen units. For a production project, I'd stick with an external resonator or crystal. Regards, Mark markrages@gmail -- Mark Rages, Engineer Midwest Telecine LLC markrages@midwesttelecine.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist