WSAL19602 – CM4-IO-BASE-B/en
Erscheinungsbild
Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.
Summary
The CM4-IO-BASE-B is a base board for the Raspberry Pi Compute Module 4 (CM4/CM4L). It provides power, USB, HDMI, Ethernet, M.2, DSI/CSI and GPIO connectivity.
Related products at JW Tech
- WSAL19602 – Mini Base Board (B) Designed for Raspberry Pi Compute Module
- WSAL20185 – Mini-Computer Based on Raspberry Pi Compute Module 4 (NOT Included), Mini IO Board Full Ver, Metal Case, with Cooling Fan
- WSAL20256 – Mini-Computer Based on Raspberry Pi Compute Module 4 (NOT Included), Mini IO Board Full Ver, Metal Case, with Cooling Fan
- WSAL20270 – CM4-IO-BASE-B + USB HDMI Adapter, for Raspberry Pi Compute Module 4
- WSAL20272 – CM4-IO-BASE-BOX-B + USB HDMI Adapter, for Raspberry Pi Compute Module 4
- WSAL24008 – Mini-Computer Based on Raspberry Pi Compute Module 4 (NOT Included), Mini IO Board Full Ver, Metal Case, with Cooling Fan
- WSAL24009 – CM4-IO-BASE-BOX-B + USB HDMI Adapter, for Raspberry Pi Compute Module 4
- WSAL24010 – CM4-IO-BASE-BOX-B + USB HDMI Adapter, for Raspberry Pi Compute Module 4
Technical overview
- Compatible with all versions of the Compute Module 4 via its dedicated CM4 connector.
- Powered through a USB-C port at 5 V / 2.5 A; the same port also serves as an eMMC image-programming interface.
- Four hardware revisions exist from V1.0 to V4; V4 fixes BT-DIS/WIFI-DIS silkscreen/pin mismatches and moves the display path from DSI0 to DSI1.
- Available interfaces include two USB 2.0 ports, Gigabit Ethernet, two HDMI ports rated 4K@30 fps, an M.2 Key-M connector for PCIe devices, a 40-pin GPIO header, and a TF-card slot available only on the Lite variant.
- The fan header supports 5 V fans exclusively; do not connect a 12 V fan.
- RTC functions use the PCF85063 chip on I2C-10 at address 0x51; the EMC2301 fan controller is also on I2C-10 at address 0x2F.
- DSI display: default resolution is 800×480; V4 uses DSI1 while earlier versions use DSI0.
- CSI cameras: single-port cameras operate only on CAM0; dual-camera setups require both ports.
- When running Bookworm, certain jumpers on the official base board must remain closed; otherwise the system may fail to boot.
- The M.2 connector supports only PCIe-channel devices such as NVMe SSDs; SATA drives are not supported.
Commands and examples – verify before use:
sudo nano /boot/config.txt
dtparam=i2c_vc=on
dtoverlay=i2c-rtc,pcf85063a,i2c_csi_dsi
#dtparam=audio=on
sudo reboot
sudo hwclock -w
sudo hwclock -s
sudo hwclock --set --date="9/8/2021 16:45:05"
sudo hwclock -r
sudo hwclock --verbose
dtoverlay=dwc2,dr_mode=host
dtoverlay=i2c-fan,emc2301,i2c_csi_dsi,midtemp=45000,maxtemp=65000
i2cdetect -y 10
libcamera-hello --list-cameras
libcamera-hello -t 0
sudo raspivid -t 0 -cs 0
sudo raspivid -t 0 -cs 1
Notes and version constraints
- No protection circuitry is present: avoid short-circuiting the power supply.
- This expansion board does not support PoE.
- While powered on, do not plug or unplug any device other than USB and HDMI.
- A 5 V 2 A power supply is required for stable CM4 operation; otherwise automatic shutdowns or frequency reductions may occur.
- Use matching screws when attaching the M.2 connector; incorrect screw lengths can damage the CM4.
- Connect the fan before powering on the board; connecting it after power-on can damage the control chip.
- The RTC battery (CR1220) must be properly seated and charged, otherwise RTC values will be invalid.
- Kernel version must be at least 6.1.31 for fan functionality.
- DSI and CSI usage are prohibited while RTC configuration is active.
Source and revision record
- CM4-IO-BASE-B - Waveshare Wiki
- Source revision: 105209
- Captured: 2026-09-02T02:35:00+00:00
- SHA-256:
1050f5c08c5bb2045cd38b209cd2235d7957f87310770db58d86a47d1908e845