I'm trying to use this:
https://www.sparkfun.com/products/449
to connect my RPi to my computer via a USB to serial device. (And eventually connect the RPi to other legacy serial devices)
My questions:
How do I determine what voltage the USB to serial device is running at? Does it matter in this case?
Assume the USB to serial device I have runs at 5V. Do I solder the Vcc pin of the PRT-00449 to 5V on the Pi or 3.3V? I was originally assuming 3.3V (which would imply that I could then use serial devices of any voltage, negating the need for question 1) until I found this page:
https://www.abelectronics.co.uk/kb/article/1035/serial-port-setup-in-raspberry-pi-os
"Connecting a 5V device to the UART port can damage the Raspberry Pi GPIO header."
I'm assuming that the above page is implying "unless you use a level shifter" but rather than risk damage, I'm asking here.
- How do I connect RX and TX of the PRT-00449 to the Pi? Does RX of the PRT-00449 go to pin 10 on the RPi? (UART RX) or to pin 8? (UART TX)
I know these are very basic questions but it is very easy to get this backwards, risking damage to my devices, so having this explicitly defined is extremely helpful.