Guide to set up the Raspberry PI 3 with ArchLinux ARMv7, plus connect to serial console via telnet

guide-setup-raspberry-pi.txt

1. Install ArchLinux ARMv7 on the SD card

Follow the guide lines in: https://archlinuxarm.org/platforms/armv8/broadcom/raspberry-pi-3


2. Configure Serial UART0 to the Linux console

Only need to disable the bluetooth on UART0 to free it to operate as linux console:
Add the following to /boot/config.txt to disable the onboard bluetooth on UART0:

dtoverlay=disable-bt

Refer to: /boot/overlays/README


3. Connect a USB to TTL converter (e.g. FTDI 'FT232RL')

FTDI  RX <---> TX  RPI (GPIO 14)
FTDI  TX <---> RX  RPI (GPIO 15)
FTDI GND <---> GND RPI

To access the serial devices on linux, add user to "uucp" on ArchLinux or "dialout" on Debian:
# usermod -aG uucp $USER

Use a serial communication program, like screen or minicom, to access the serial device on any of
/dev/ttyUSB0, /dev/ttyS0 or other numbers.

Refer to: https://www.raspberrypi.org/documentation/configuration/uart.md


4. Configure ser2net to access the serial via telnet

Install ser2net and configure a connection on /etc/ser2net/ser2net.yaml:

connection: &con1
  accepter: telnet(rfc2217),tcp,2002
  timeout: 0
  enable: on
  connector: serialdev,/dev/ttyUSB0,115200n81,local
  options:
    banner: "Welcome to the Mini-computer (Raspberry PI 3)"
    
Refer to: https://github.com/cminyard/ser2net/blob/master/ser2net.yaml
    
Start up the ser2net service:
# systemctl start ser2net.service

Connect to the telnet session:
$ telnet 0 2002