The CM3-Panel is fully compatible with the Raspberry Pi 3 but it maps the peripherals on different pins. For this reason some files have to be added an some other have to be modified.
This articles has been verified with Raspbian Buster Desktop and Lite version July 2019
Create a standard microSD following the official instruction on:
Mount the MicroSD just created on your PC. The first partition boot is formatted as FAT32 and so is visible on Windown, Mac and Linux PC.
These are the files to changes:
and these are the files to create:
While booting up, the Raspberry Pi reads some configuration parameters from the first partition of MicroSD card.
These parameters are stored in a file called config.txt inside the first microSD partition.
You can edit this configuration from any PC because the first partition is formatted as FAT so it can be read with Mac, Windown or Linux. Use an ASCII editor like Nodepad or similar (please don't use Word :-) and add these lines at the end of this file:
#Ignore the HDMI cable hotplug (to avoid the delay at startup) hdmi_ignore_hotplug=1 # Set the debug port on GPIO32, GPIO33 pins force_turbo=1 dtoverlay=uart1,txd1_pin=32,rxd1_pin=33 # Is not requested to insert this line #enable_uart=1 # Activates the I2C 1 port on GPIO44 and 45 to talk with the # touch screen controller end camera crypto-chip dtoverlay=i2c1-bcm2708,sda1_pin=44,scl1_pin=45,pin_func=6 dtoverlay=goodix-7-acme ## Enable the DPI port to talk with the TFT display dtoverlay=dpi18 overscan_left=0 overscan_right=0 overscan_top=0 overscan_bottom=0 framebuffer_width=800 framebuffer_height=480 enable_dpi_lcd=1 display_default_lcd=1 dpi_group=2 dpi_mode=87 dpi_output_format=0x6f005 hdmi_timings=800 0 40 48 88 480 0 13 3 32 0 0 0 60 0 32000000 6
Comment this line to disable the audio section not used on this board
# Enable audio (loads snd_bcm2835) # dtparam=audio=on
The file cmdline.txt contains some parameters passed to the Linux Kernel during the boot. To enable the serial debug port changes:
This file is used to enable the capacitive touch.
You can just save this binary file in the overlays directory:
or compile it from this source:
To compile it save the source on the microSD and use the dtc (Device Tree Compiler) on the Raspberry Pi after the boot with this command:
sudo dtc -@ -I dts -O dtb -o /boot/overlays/goodix-7-acme.dtbo /boot/overlays/goodix-7-acme.dts
This file defines the Raspberry camera I2C lines used on the CM3-Panel.
You can just save this binary in the microSD:
or compile it from the sourse:
To command to use is:
sudo dtc -I dts -O dtb -o /boot/dt-blob.bin /boot/dt-blob.dts
To use the camera enable is using the utility:
By default the SSH server is disabled on the Raspbian microsd images. To enable it create an empty file called SSH with no extention on the first microSD partition. The ssh server will be enabled at first startup and you can reach the Linux command prompt via lan.
ssh firstname.lastname@example.org Password: raspberry
sudo apt-get update sudo apt-get install python-picamera
Save this python example in grab.py
from picamera import PiCamera from time import sleep camera = PiCamera() camera.start_preview() sleep(10) camera.stop_preview()
and run it by typing: