I often do 3.3V to 5V translation using a 74HCT part. These have TTL input thresholds that will work with 3.3V logic. With the TinyLogic parts, one part does the job. For the other way (5V to 3.3V), if the speed is not too high, I just use a resistive voltage divider. Harold FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available! Not sent from an iPhone. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .