Raspberry Pi Compute Module 4 PoE IO Board

Note: The Compute Module is not included, please choose your preferred CM4 from here:

• Raspberry Pi Compute Module 4 WITH Wireless - Pick RAM and eMMC Size
• Raspberry Pi Compute Module 4 WITHOUT Wireless - Pick RAM and eMMC Size

Compute Module 4 is official launched on 19th October 2020 with the same or better spec, and there are 32 variants of the module to choose from. Since there are quite significant upgrades on Compute Module 4 compares to its predecessor (CM3 or CM3+), you will need a new IO board for it. This is the IO board with PoE (Power Over Ethernet) capability.

IO Board with PoE for Raspberry Pi Compute Module 4

This PoE CM4 IO board breakouts quite some extra peripheral ports if we compared it with Raspberry Pi 4 Model B:

• 2 x DSI display port - The DSI connectors are 22-way 0.5mm pitch to pitch. These connectors are the same as the existing CMIO board but different from the Raspberry Pi 4 Model B.
• 2 x CSI camera input port - The CSI connectors are 22-way 0.5mm pitch to pitch. These connectors are the same as the existing CMIO board but different from the Raspberry Pi 4 Model B. Now you can get an extra camera input on the CM4 IO board. The CSI connectors are compatible with the Raspberry Pi Zero CSI connector, so the FFC/FPC cable can be utilized for the camera module interface on the CM4 IO board.
  • 15cm Raspberry Pi Zero CSI FFC/FPC cable
  • 30cm Raspberry Pi Zero CSI FFC/FPC cable
• 4 x USB 3.2 Gen1 Port - This board provides four, not two USB 3.0 ports and those like to connect to high-speed SSD Storage.
• 2 x Full-Size HDMI port - Again, support dual displays
• 1 x Cooling Fan connector - Support standard +12VDC cooling fan with PWM drive and tacho output. An EMC2301 controls the fan via I2C.
• 1 x RTC with Coin Cell Socket - for onboard Real Time Clock keeping time running even after the CM4 and IO board is power off.
• 1 x DC Barrel Jack - A DC Barrel Jack with 5.5mm*2.1mm, accepting a wide range of input voltage to power the IO board. Ranging from 7V to 36VDC.
• 1 x USB Micro B Slave port - There is a USB Micro B port for CM4 to be updated via rpiboot.
• 1 x MicroSD card socket (at the bottom of PCB) - This is only meant for CM4 Lite as it does not come with onboard eMMC memory for Operating System and will require external memory to boot. This PoE CM4 IO board comes with a push-push type socket :)

Board Layout

1. CM4 socket - suitable for all variants of Compute Module 4

2. Power input - DC Barrel, accepting 7~36V wide-range power supply

3. Gigabit Ethernet connector - Gigabit Ethernet RJ45 with PoE support

4. USB SLAVE port - allows burning system image into Compute Module 4 eMMC variants

5. USB3.2 ports - 4 x USB 3.2 Gen1 ports, for connecting sorts of USB devices

6. HDMI ports - 2 x HDMI ports, supports dual 4K 30fps output

7. RTC - RTC battery holder allows RTC-related functions like wakeup, shutdown, reboot, and more

8. CSI Camera port - 2 x MIPI CSI camera ports

9. DSI DISP - 2 x MIPI DSI display port

10. FAN - for connecting cooling fan, allows speed adjustment and measurement

11. FAN power selection - 5V or 12V voltage to drive the fan

12. IO-VREF/PoE selection - CM4 IO logic level: 3.3V or 1.8V,  PoE: enable (EN) or disable (DIS)

13. 40PIN GPIO header, color-coded

14. CAM0 and DISP0 I2C bus - fit the jumpers when using CAM0 or DISP0

15. Misc configurations

16. Dual LED indicators -red: Raspberry Pi power indicator, green: Raspberry Pi operating status indicator

17. TF card slot (bottom side) - insert a Micro SD card with a pre-burnt system, to start up Compute Module 4 Lite

Note: The CSI on the PoE CM4 IO board is compatible with the Raspberry Pi Zero CSI connector, so you can utilize the FFC/FPC cable for Raspberry Pi Zero to interface with the camera module.

Note: However, the DSI port on PoE CM4 IO Board is NOT COMPATIBLE with the FFC cable for RPi Zero.

Note: If you get the CM4 with eMMC, this video and blog post by Jeff Geerling is helpful for you to flash the eMMC with the OS that you want:

Comparison between Official CM4 IO Board

Features and Spec:

• Specially designed for CM4, with PoE capability
• Accepts the complete range of CM4 modules, all 32 variants:
  • Raspberry Pi Compute Module 4 WITH Wireless - Pick RAM and eMMC Size
  • Raspberry Pi Compute Module 4 WITHOUT Wireless - Pick RAM and eMMC Size
• Wide Range of Power Input via DC Barrel Jack 5.5mm*2.1mm, 7V to 36VDC.
• 2 x Full-size HDMI 2.0 connectors
• Gigabit Ethernet RJ45 with onboard POE support
• 4 x USB 3.2 Gen1 Socket.
• USB Micro B socket for updating the CM4's onboard eMMC
• MicroSD Card socket for CM4Lite modules, Push-Push socket
• Standard Cooling Fan connector, support PWM and Tacho feedback
• 2 x MIPI DSI display FPC connectors ( 22pin 0.5mm pitch cable)
• 2 x MIPI CSI-2 camera FPC connectors ( 22pin 0.5mm pitch cable)
  • It is compatible with the Raspberry Pi Zero CSI connector, so please get the FFC/FPC cable for Raspberry Pi Zero if you do not have one.
• Raspberry Pi HAT connector, the Color Coded 40-pin GPIO, and the PoE 4-pin header
• RTC with Battery socket and ability to wake up CM4
• Various jumpers to disable features e.g Wireless, EEPROM writing
• Dimension: 160mm x 90mm

• 1 x Raspberry Pi Compute Module 4 PoE IO Board

• CM4 PoE IO Board Wiki Page
• How to flash Raspberry Pi OS onto the Compute Module 4 eMMC with usbboot, by Jeff Geerling with video
• Compute Module 4 datasheet