This is just killing me. I have several USB to serial TTL devices. SOme put out only +3.3 volts, others only +5 volts while another has a jumper that will allow you to Vcc out either 3.3 or 5 volts. My read dilemma is this on PL 2303 I got off ebay. It has a Vcc +5 and +3.3 out put the Tx/Rx always…

[solved] USB to Serial TTL Question

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