SPI (Serial Peripheral Interface)
Synchronous serial communication protocol with a dedicated clock line.
- 4 wires: SCK (clock), COPI (Controller→Peripheral), CIPO (Peripheral→Controller), CS (Chip Select)
- Full-duplex: simultaneous bidirectional data transfer
- CS is active LOW — controller pulls CS low to select a peripheral
- Multiple peripherals: each needs its own CS line
- Faster than I2C, more wires
Old names (deprecated): MOSI/MISO/SS
See Also
- Serial Protocols topic