Consequently, the same GPIO can be used to read digital bits as well. A traditional microcontroller like the 8051 is available in DIP packages ranging from 20 pins to 40 pins.

The device actually has RS232, I2C, SPI, and 8 general purpose I/O (GPIO) pins. [ZooBaB] took an out-of-tree driver that exposes the GPIO, and got it working with some frightening-looking CH341 ...

To make the test possible, the chip must have more than one GPIO. This way, they can be paired, bringing the opportunity for the members of the pair to poll each other. Since the activity of the GPIO ...

– Four optically isolated open collector outputs (Controlled by GPIO pins 11, 12, 13, and 15) – Four optically isolated inputs (24VDC max) (Controlled by GPIO pins 7, 16, 18, and 22) ...

A novel family of advanced fixed-direction voltage level translators developed by Nexperia targets the most common push-pull data interfaces (including UART, SPI, and JTAG protocols) as well as ...