Serial port on GPIO header simply does not work.
I put a 1GHz oscilloscope on it, while trying to send data. I could see maybe a 20mV variation, the TX signal was always high.
I disabled the serial console.
This was with the latest “Raspbian” image.
I also tried the Banana Pro Raspbian, that did not work either.
This has been delaying my review for about six weeks now…
FYI,
The latest Raspbian image also does not have a kernel module for the on-board WiFi, but that worked with the Banana Pro image.