Raspberry Pis

5

Connectors

The Pi 5 (and some Picos I think) have a UART connector. It seems to be a JST SH. The plug is, however, called JST SR. 1mm pitch.

Pi 5 UART max 921,600bps.

The same connector is use on some Picos and the Debug Probe for SWD.

Pinout

1	2	3
RX	GND	TX
SWCLK	GND	SWDIO

USB https://datasheets.raspberrypi.com/debug/debug-connector-specification.pdf

WiFi

Show stations connected to the pi's AP: iw dev wlan0 station dump

Power

Does not do well on brownout. It didn't come back up when voltage dropped on high resistance cable. I found it with red LED on. Didn't power up properly until replugged, twice. There was also some data loss on the SD card.

According to a forum post, will not power on itself if powered on GPIO pins. It can run, but needs power button pressed.

USB

Power Switching

Switches, off then on, power to USB ports. Apparently you can't do them individually, but need to turn them all off to get any of them to go off.

This needs a recent version of uhubctl - the version in Raspbian didn't work. I built from git.

usb_powercycle

#!/bin/bash
 
uhubctl -l 1 -a 0
uhubctl -l 2 -a 0
uhubctl -l 3 -a 0
uhubctl -l 4 -a 0
 
sleep 3
 
uhubctl -l 1 -a 1
uhubctl -l 2 -a 1
uhubctl -l 3 -a 1
uhubctl -l 4 -a 1