I2C using SC126 and PCF8574
This example shows how to add a simple I/O expander chip to the I2C port of SC126 (Z180 SBC/Motherboard).
The PCF8574 provides 8 input/output lines, each of which can be written to or read from. Each input/output line can be set low (open collector) or set high (weak pull-up). The input/output line can also be read, allowing it to act as an active low input when set to output high.
Source code and other files can be found here.