Even despite SPI’s simplicity ... so a system that samples on the upswing will have phase = 1 — sampling on the second transition. My head hurts even writing it out. Here’s how I cope.

[Mike] wanted to drive several SPI peripheral from a PIC32. He shows how much latency his conventional interrupt handlers were taking away from his main task. He needed something more efficient.

It enables the microcontroller to communicate with fast serial SPI memories and serial peripheral devices. Moreover, it’s capable of inter processor communications in a multi‐master system. A serial ...