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SPI簡介

SPI ( Serial to Peripheral) 是一種通訊模式

1.同步(就是有clock)

2.Master/Slave

3.4 wired ( MOSI MISO CLK SS)

4.bi-direction (全雙工)

NANO130 Features

• Supports Master (max. 32 MHz) or Slave (max. 16 MHz) mode operation

• Supports 1 bit and 2 bit transfer mode

• Support Dual IO transfer mode

• Configurable bit length of a transaction from 8 to 32-bit

• Supports MSB first or LSB first transfer sequence ( 就是 Big Endian 跟 Small Endian )

• Two slave select lines supported in Master mode

• Configurable byte or word suspend mode

• Supports byte re-ordering function

• Supports variable serial clock in Master mode

• Provide separate 8-level depth transmit and receive FIFO buffer

• Supports wake-up function

• Supports PDMA transfer

• Supports three wires, no slave select signal, bi-direction interface

Block Diagram

給個Clock ，不能比APB高，Slave Mode 要比 Master高

Master/Slave


 

Master 可接 2 組 Slave

時序圖與基本測試

基本測試

SS=0

虛線1.把MOSI資料準備好 > SCLK = 1

虛線2.讀取MISO > SCLK = 0

repeat…

SS=1

SPI 的通訊在底層比 I2C 簡單，但再往上會比較複雜

再去找個SPI裝置來兜

下一篇 就往上走與裝置溝通，並使用邏輯分析儀分析訊號