Compute Module • Compute Module 4 GPIO Function Guide

Hi,

I have gone through various forum posts claiming conflicting things and would like to put all the findings in place and clarify things.

GPIO function availability depends on CM4 board and is summarised in following categories:-

CM4 Lite (No EMMC, No Wireless)
CM4 Lite (No EMMC, With Wireless)
CM4 (With EMMC, No Wireless)
CM4 (With EMMC, With Wireless)

Information gathered from various forums: (needs clarification, which of these statements are true?)
1. If equipped with wireless, BT is connected using UART0 function via internal GPIO 30-33.
2. If equipped with wireless, WiFi is connected using SD1_x function via internal GPIO 34-39.
3. If equipped with EMMC, it is connected using SD0_x function via internal GPIO 48-53.
4. If equipped with EMMC, it is connected via dedicated interface and doesn't use any GPIO functions.
5. If NOT equipped with EMMC, the dedicated interface is available via SDx pins for SD Card or SDIO Flash.
6. Ethernet PHY is connected using RGMII via internal GPIO 28-29 and 48-53.
7. On-board SPI ROM is connected using SPI(unknown) via internal GPIO 40-43.

Any clarification would be highly appreciated.
Thank you.

Statistics: Posted by xkam1x — Sat Mar 09, 2024 2:37 pm

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