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Table of Contents
CPI-C IO Features
Rear Panel IO
The CPi-C series panel PCs have a 26-pin header socket on the rear panel with the following pinout.
See pp.8 of the Compute Module 4 datasheet for more information.
The GPIO pins are not exposed through a level shifter like the CPi-S panel PCs, so the internal pull-up/-down resistors can be utilized. GPIO45 has an internal 1.8kohm pullup resistor to 3.3V because it is initially used for I2C (See Table 6 of the Compute Module 4 datasheet).
The 5V pins can supply a maximum current of 1A. The 3.3V pins can supply a maximum current of 700mA. If both 5V and 3.3V rail pins are used simultaneously, their total power should be kept below 5 watts.
The panel PC's RTC is connected to I2C1, so those pins assigned to I2C1 should not be reconfigured.
Side Panel IO
The right panel of the CPi-C panel PCs expose a MicroSD card slot and a stereo audio output jack.
For models with an eMMC, the MicroSD card slot is not electrically connected, so it cannot be used.