PCB should be assembled on SMT machines followed by the through-hole process, building to the BOM.

1. Visually check all connectors for soldering quality. Pay special attention to the 2×100-pin connectors.
2. Ensure that through-hole components are soldered flush to the board
3. Ensure that the CM4 is fully inserted in the 2×100 pin connectors
4. Proceed to do a general quality check of the soldering of the printed circuit board

Once the PCB has been assembled and quality checked, the unit can now be programmed.

Navigate to http://192.168.16.47/ and sign in with the following credentials:

At the top of the screen, select “Projects”.

Then, choose the version to install, such as “P19 - Generic” or “P19 - HCB” according to the build order, by selecting “Set Active” next to its entry.

You can now connect any number of P19 PCB's to the programming rig, by first connecting the ethernet cable and then the power cable. If the CM4 has already been programmed (which is the case for all CM4's in stock at 22/11/2023), then you will instead need to use the “Rescue Board”.

To use the “Rescue Board”, plug the CM4 into the board, then attach the USB cable, ethernet cable and then power supply cable.

For both methods, wait 5 minutes and then the board will be programmed automatically.

1. Extend the P19 TFT backlight cable by 20cm. Heat-shrink the connections.

2. Install the rubber blanking cap (PN x) into the case.

3. Install the plastic vent (PN x) into the case.

4. Apply foam tape to the inside of the case rim as pictured.

4. Remove the screw-on nuts from the black plastic connectors. Do not remove the rubber seal.

5. Apply thermal paste (PN x) to the CM4 CPU die

6. Insert the PCB into the case. Affix using 1 washer (PN x) and screw (PN x) per corner as pictured.

7. Replace the screw-on nuts on the connectors on the rear of the case and tighten using supplied sockets. Take care to ensure the final orientation is as pictured.

8. Attach the backlight cable.

9. Attach the LVDS cable.

10. Lower LCD into case, insert 4x screws (PN x) into the mounting holes as shown. Be careful to keep LCD centered in the case.

The unit is now ready for testing.

1. Clean the screen with a soft cloth and glass cleaner

2. Apply a bead evenly all the way around the screen as shown

3. Return to the screen after 10 minutes and fill any areas that have sunk

4. Leave to cure for 12 hours

5. Clean any excesses from the metal and glass

6. Apply protective film to the screen

On Linux computer clone the following repository:

git clone --depth=1 https://github.com/raspberrypi/usbboot
cd usbboot
make
cd recovery
./update-pieeprom.sh 

Mount the Raspberry Pi CM4 on the test IO board. Connect the IO board to the host Linux computer with USB to USB cable.

Now use rpiboot on Linux computer to start the CM4 in Mass Storage Mode.

cd usbboot
sudo ./rpiboot

Power up the IO board. After a few moments, one or more drives will appear on the host Linux computer. You can display these devices using the following:

lsblk

Which will produce output similar to the following:

NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
sda           8:16   0 223.6G  0 disk 
├─sda1        8:17   0   529M  0 part /media/user/boot
├─sda2        8:18   0    99M  0 part /media/user/rootfs_A
├─sda3        8:19   0    16M  0 part /media/user/rootfs_B
└─sda4        8:20   0   223G  0 part /media/user/homefs

You now need to clear the device that is mounted at /media/user/boot, which is sda1, as follows:

sudo rm -R /media/user/boot
sync

Then one final action is needed to reset that to factory settings:

cd usbboot
sudo ./rpiboot -d ./recovery

Reboot the IO board and the device’s bootloader will be replaced with the default.