I've got an application here that requires reading in RS-232 data at MANY DIFFERENT possible "non-standard" baud rates. These baud rates range from 4800 to near 49k baud.

In some simple tests, I found it very difficult to receive bytes at some of the higher rates (49k) without error. For the tests, I used a processor that was capable of reading in increments of 200ns machine cycles. I used a "change on pin" interrupt to detect the start bit and then manually delayed to the middle of each of the 8 bits. In my simulator, the bit times were extreamly close to the target, so I figured it would have worked.

I've got two questions:

1) Can a processor read high-rate bytes with bit-banging at 200ns resolution?

2) With the complexity of supporting a large number of rates (i determine the rate by measuring the devices frequency), is there a better way to do this besides a "different delay" for each baud? Possibly a seperate device that would translate the odd timings to a rate I could easily handle?

Thanks for any information!
Henry