There are two RISC-V computers on my desk – photos eventually – and they are moving towards “just work” state, but they do occasionally swerve back into the default state of single-board-computers everywhere: there’s a serial port and you’re gonna like it.
From work a few years back with all the Pine64 boards, I have a handful of USB-to-serial converters (and just ordered another one from Pine as a backup), but getting the pins right is always a pain. I’ve considered wiring up better connectors, but never really gotten around to it.
As a stop-gap, I’m going to post (possibly for my own benefit as a backup easy-to-find resource) pinouts for the StarFive VisionFive V2 and the Pine64 Star64 boards. Now that I’ve written this down, I can finally remember “6=GND, 8=TX, 10=RX”.
I have a StarFive VisionFive V2 board, but the pinout is the same as in this image, which I have screenshotted from the StarFive 40-Pin GPIO Header User Guide PDF which is available on the rvspace.org site and elsewhere.
I have a production-run Pine64 Star64 board, which has a wiki page that links to a schematic. Zooming in gets me this screenshot.