commit 83641a69259dcb4365ecc4f435d1a296bdaab283
Author: GNU <dexterkidd@gmail.com>
Date:   Thu Sep 2 11:43:37 2021 +0800

    Devterm CM3 rpi os image

diff --git a/Devterm-CM3-rpi-os-image.md b/Devterm-CM3-rpi-os-image.md
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+### Orginal image download URL
+https://downloads.raspberrypi.org/raspios_full_armhf/images/raspios_full_armhf-2021-05-28/2021-05-07-raspios-buster-armhf-full.zip
+
+
+#### Modification request list 
+- [x] chromium downgrade to 84.0.4147.141 
+- [x] screen rotation for xrandr,fbcon,lightdm
+- [x] Remove the wallpaper and change the solid color #202020  
+- [x] Install all rpi-related debs in the apt source 
+
+#### Packages in apt source
+1. devterm-audio-patch (check whether the 3.5 audio interface is plugged in, pull up a certain GPIO)
+1. devterm-fan-temp-daemon-rpi (detect the temperature of rpi, raise the io drive fan, written in python)
+1. devterm-kernel-rpi (modified kernel, 4.x series)
+1. devterm-keyboard-firmware (Devterm keyboard firmware flashing tool, Advanced users only!)
+1. devterm-thermal-printer (thermal printer program and systemd scripts)
+1. devterm-thermal-printer-cups (CUPS filter for the thermal printer, and add the thermal printer to cups, so devterm printer can be seen in chromium) 
+
+
+
+
+##### Add clockworkpi to /etc/hosts, then install devterm related apt, see https://github.com/clockworkpi/apt/tree/main/debian 
+```
+wget -O - https://raw.githubusercontent.com/clockworkpi/apt/main/debian/KEY.gpg | sudo apt-key add -
+
+echo "deb https://raw.githubusercontent.com/clockworkpi/apt/main/debian/ stable main" | sudo tee -a /etc/apt/sources.list.d/clockworkpi.list
+```
+
+##### Config xrandr 
+```
+sudo bash -c 'cat << EOF > etc/X11/Xsession.d/100custom_xrandr
+xrandr --output DSI-1 --rotate right
+EOF'
+```
+
+##### Config lightdm
+in `/etc/lightdm/lightdm.conf`
+```
+greeter-setup-script=/etc/lightdm/setup.sh
+```
+*setup.sh*
+```
+#!/bin/bash
+xrandr --output DSI-1 --rotate right
+exit 0
+```
+`sudo chmod +x etc/lightdm/setup.sh`
+
+
+##### Modify /etc/dphys-swapfile
+```
+CONF_SWAPSIZE=512
+```
+
+##### Change the default wallpaper
+The following files changed 
+
+* /etc/xdg/pcmanfm/LXDE-pi/desktop-items-0.conf 
+* /etc/xdg/pcmanfm/LXDE-pi/desktop-items-1.conf 
+* /etc/lightdm/pi-greeter.conf 
+* /home/pi/.config/pcmanfm/LXDE-pi/desktop-items-0.conf 
+* 
+Delete wallpaper address temple.jpg
+Modify the desktop_bg color to #202020 
+
+
+
+#### config.txt
+
+Add dtparam=audio=on to solve the problem of no sound card under HDMI
+
+##### /etc/hostname to clockworkpi
+
+##### /boot/cmdline.txt ,add fbcon=rotate:1, remove quiet 
+
+### Image download url
+https://mega.nz/file/FV1wyC4A#PJJhEpzb6kk28GTKPcRS8qikviQDo7igCNHfItamCOo
+4740f676b838d3ff1299b2147f062729 2021-05-07-raspios-buster-armhf-full_devterm.7z