The Compute Module 4 IO Board is a companion board for Raspberry Pi Compute Module 4 (supplied separately). It is designed for use both as a development system for Compute Module 4 and as an embedded board integrated into end products. 

The IO board is designed to allow you to create systems quickly using off-theshelf parts such as HATs and PCIe cards, which might include NVMe, SATA, networking, or USB. The major user connectors are located along one side to make enclosures simple. 

Compute Module 4 IO Board also provides an excellent way to prototype systems using the Compute Module 4.

• Upgraded processor BCM2711, quad-core Cortex-A72 (ARM v8) 64-bit SoC, more powerful performance
• More options for RAM (1GB/2GB/4GB/8GB), competent for large-scale data compilation
• Faster eMMC Flash storage, up to 100 MBytes/s data rate, which is four times faster than the CM3+
• Option for fully certified radio module, the same one used on Pi4B, supports either PCB trace antenna or external antenna, more suitable for industrial applications
• Adopts B to B connectors, more stable than the Goldfinger edge connector of previous generations
• Onboard new Gigabit Ethernet PHY supporting IEEE1588, suitable for network applications
• Onboard new PCIe Gen 2 x1 interface, allows connecting more useful modules

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