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dom123dom · 12-26-2018, 05:05 PM

I'm learning more as i experiment, so I will update here when I overcome things...I found my multimeter, plugged the USB to serial board into my computer and notice voltages as follows on the pins:

RX = 2.9v
TX = 3.3v

I'm not sure why these are different, I was expecting 3.3v on both pins.

If I set the jumper to 5v there is a similar slightly lower voltage on the RX pin. I'm expecting the voltages to drop on all pins once I have the LDO in place.

I have decided not to order the cable for now since I have almost all the parts, but I will probably still use the sewing pin technique to connect to the kindle.

12-26-2018, 05:05 PM	#28
dom123dom Zealot Posts: 106 Karma: 10 Join Date: Dec 2018 Location: Sydney, Australia Device: Kindle Paperwhite 2 WiFi 4Gb 2013 (s/n 9017..)	I'm learning more as i experiment, so I will update here when I overcome things...I found my multimeter, plugged the USB to serial board into my computer and notice voltages as follows on the pins: RX = 2.9v TX = 3.3v I'm not sure why these are different, I was expecting 3.3v on both pins. If I set the jumper to 5v there is a similar slightly lower voltage on the RX pin. I'm expecting the voltages to drop on all pins once I have the LDO in place. I have decided not to order the cable for now since I have almost all the parts, but I will probably still use the sewing pin technique to connect to the kindle.