Ya, that voltage difference | Microcontroller › PIC › RFID MF522 – AN and PIC 18F4550 › Ya, that voltage difference September 15, 2014 at 5:06 am #12181 AJISH ALFREDParticipant Ya, that voltage difference need to be taken care of. The max232 is no the right device for this. There are 3v – 5v bidirectional level shifter ics and modules available.
