Software Installation Guide of CM4 IO Case
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Special Notice:
ON/OFF switch of CM4 IO Case is driven by Bootloader & 40pin GPIO driver of
CM4, so it controls the system on/off by software. It is not a traditional switch which
cut off or turn on the power supply of the board. Forcing the power shutdown during
CM4 operation may damage the file system and cause the system crash. It is highly
recommended to implement the system on/off by our software code.
GPIO3 on 40pin connector is used for one-click switch. We define the signal as
a GPIO instead of SCL1 of I2C. Please remap the I2C function to another pin since
this signal has been used to implement one-click switch function.
Fan is directly powered by +12V DC power, the system doesn’t control the fan,
if you want to turn off the fan after the system is shut down, you have to remove the
power system of CM4 IO board. We will upgrade the fan and software in next
version.
1. Preparation
The following hardware and software should be prepared before you start.
Linux host to program the bootloader into CM4 ( we use PI3B+ as
a host in the document, you can use Pi4 or other Raspberry Pi
computer)
