Thanks for the info! This particular application is a polled system, and my local PIC needs to process data and format the output into a predefined 'message'. Then when I am polled, I need to forward the data on to the host. I think ARRAYWRITE is the way to go. I was thinking about using an eeprom, but this is definately faster. I am not sure of the time between the polls yet though, and am concerned my data will back up, so need some message buffer space. Thanks very much for your help.