[Adam Shapiro]

Originally Posted by Nathan

I thought that's what printf did?

Printf converts the data you pass to it into a human-readable string format. For instance, the value 100 would be converted into the following three characters: '1' '0' '0'. What Kevin is suggesting is for you to simply send the byte values themselves out of the serial port. This can be done very quickly and won't impact the ISR very much. You can then read those values into the computer and view them at your leisure, or record them and process them with an additional application (which may be quite useful for what it seems you're trying to do).