Some notes for running Unipager with a UDRC-II on a Raspberry Pi 2B. Tested with an Icom IC-9100 and a Motorola GM360 UHF transceiver.

• Raspberry PI 2B
• Power supply
• Micro SD Card
• UDRC-II Hat
• Raspbian Buster lite
• 6 pin DIN cable
• 70cm band transceiver with 9600 baud data (6pin din) input

• Write image to SD-Card

  sudo dd if=2020-02-13-raspbian-buster-lite.img of=/dev/sdX bs=8M oflag=direct status=progress

• Configure hostname

  /etc/hosts
  /etc/hostname

• Enable SSH

  touch /boot/ssh

• Connect via ethernet (DHCP)
• Update

  apt update
  apt upgrade

• Check UDRC-II hat connection

  # grep -a "" /proc/device-tree/hat/*
  /proc/device-tree/hat/name:hat
  /proc/device-tree/hat/product:Universal Digital Radio Controller II
  /proc/device-tree/hat/product_id:0x0003
  /proc/device-tree/hat/product_ver:0x0003
  /proc/device-tree/hat/uuid:40dff019-4c58-48c6-87a4-12d1d0279515
  /proc/device-tree/hat/vendor:NW Digital Radio

• Configure driver, disable internal audio

  /boot/config.txt 
  [all]
  #dtoverlay=vc4-fkms-v3d
  force_turbo=1
  dtoverlay=
  dtoverlay=udrc
  #dtparam=audio=on

• Reboot
• Check if UDRC is available

  aplay -l
  **** List of PLAYBACK Hardware Devices ****
  card 0: udrc [udrc], device 0: bcm2835-i2s-tlv320aic32x4-hifi tlv320aic32x4-hifi-0 [bcm2835-i2s-tlv320aic32x4-hifi tlv320aic32x4-hifi-0]
    Subdevices: 1/1
    Subdevice #0: subdevice #0

• Configure 6pin DIN udrc-alsa-din6.sh.

  curl -L -s https://raw.githubusercontent.com/nwdigitalradio/udrc-tools/master/scripts/udrc-alsa-din6.sh | sudo sh

• Install Unipager
• Open the webinterface http://<your-pi>:8073/
• Configure callsign, authkey, see: https://hampager.de
• Set device to Audio
• Set GPIO to 4 (GPIO23 = WiringPi 4)
• Set audio output level for 4,5kHz deviation (check with SDR) and store settings:

  alsamixer
  sudo alsactl store