waveshare Compute Module 4 to Pi 3B/3B+ Adapter, Based on Compute Module 4 to Reproduce Original Appearance of Pi 3B/3B+, Alternative for Raspberry Pi 3 Model B/B+, Compatible with Pi 3B Series Hats

Compute Module 4 to 3B Adapter, Alternative Solution for Raspberry Pi 3 Model B/B+. Based on Raspberry Pi Compute Module 4, using Compute Module 4 to reproduce the original appearance of the Raspberry Pi 3 Model B/B+. Note: Compute Module 4 is NOT included.
Onboard standard Compute Module 4 connector, support access to Compute Module 4 Lite / eMMc series boards with Quad Core Cortex A72 64-bit processor, more powerful performance. Adding CM4 with this adapter board, can replace Raspberry Pi 3 Model B/B+.
Easily compatible with the interfaces of Raspberry Pi 3B / 3B+ boards. Onboard headphone jack (extended from USB). Onboard 4-ch USB ports, compatible with USB 2.0 / 1.1 transmission. Onboard RJ45 Gigabit Ethernet port, 10 / 100 / 1000 M adaptive. Onboard PoE header, for connecting PoE HATs. DSI interface is DSI1.
Compatible with Pi 3B Series HATs: Easy access to Pi 3B series HATs or other development projects
Please do not connect to other devices when programming the image by micro USB so as to ensure that CM4 can be powered on normally. When using CM4, you need to provide 5V/4A to CM4. Otherwise, it may power off, lower frequency, etc. USB 2.0 is close by default, if used dtoverlay=dwc2,dr_mode=host should be added in config.txt. It only supports 5V fan. (12V is not supported.) Please check it before connecting the fan, and note that the speed of the 5V fan cannot be adjusted without a controller.