Thanks Darrel, that definitely helps clear things in my head. I kept merging the two types of interrupts in my mind for some reason, which through me off when trying to understand the data sheet.

Unfortunately, it looks like the interrupt will not allow me to do what I was hoping for after all. I have an 8 pin micro that monitors signal from two sources and whenever there is a change on either pin it passes the signal along a third pin to a 40 pin chip. I was hoping to get rid of the 8 pin chip and use interrupts to take the two signals with IOC and pass them out a third pin which was tied to my original serial pin and use serin2 to get the data as before. It appeared to work with 1200 and 2400 baud, but when I went to anything faster the data became unusable. The interrupt must just be too slow to do everything needed before missing bits.

Thanks for the help though,
David