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When implementing a certain input and output that requires GPIO, we found that the available GPIOs on the 40-pin connector are relatively few. The available GPIOs can be seen in the Docs link.https://docs.khadas.com/products/sbc/vim3/applications/gpio/40pin-header
To achieve this, we have removed the original functionality of the pin and enabled GPIO control. This way, any pins you don't need can be fully utilized to expand more GPIOs.
Among the limited available pins, we can set the SPDIF, UART, and I2S groups as GPIOs for use when they are not in use.