A simple compute module 4 cluster in a 120x120x60mm form-factor cabable of up to 7 pi.
Each pi can work alone as a 78x58mm SBC.
Ports(per pi): 4 usb2.0, usb-c OTG, PCIE, 2 micro HDMI, CSI, DSI, micro SD and headers
The last six pin on the standard 40 way header has been removed on the board, include GPIO 16,19,20,21,26 and GND
SPI, I2C, UART are not affected, a standard HAT device can still be used.
The main board is powered by +12v through barrel jack or 4/8 pin PSU power. When the pi is alone, it could be powered through USB-A or pin headers
Two space left for EEPROM on the main PCB can be left open if custom program for the RTL8370 is not required. SW2 is a restart switch of RTL8370.
Requirement: kiCad version 5.99 or above