1. GPIO Pin Expansion Using I2C Bus Interface in Altera MAX Series
To reduce package size and pin count, the number of general purpose I/Os are limited in many microprocessor-based systems. However, if the system has an I2C interface, this design example shows how to add additional GPIO pins via the I2C bus.
The supported Altera devices are an excellent choice to implement industry standard interfaces, such as the I2C. Their low power, easy power-on feature, and internal oscillator make them ideal programmable logic devices to implement applications such as I2C interfaces to provide GPIO pin expansion.