其实是对这张图的理解。   图1： 通道1 是SPISTE信号，通道2是CLK信号，通道3是28035接收到的信号 SPICCR.6  SPICTL.3 = 00（上升沿无延时：The SPI transmits data on the rising edge of the SPICLK signal and
receives data on the falling edge of the SPICLK signal）即在下降沿接收信号，第4个下降沿接收到0   图2：SPICCR.6  SPICTL.3 = 01（上升沿有延时：The SPI transmits data one half-cycle ahead of the rising edge of the SPICLK signal and receives data on the rising edge of the SPICLK signal）即在上升沿接收信号，第5个上升沿接收到0 • Falling Edge Without Delay（SPICCR.6  SPICTL.3 = 10）. The SPI transmits data on the falling edge of the SPICLK and receives data on the rising edge of the SPICLK.
• Falling Edge With Delay（SPICCR.6  SPICTL.3 = 11）. The SPI transmits data one half-cycle ahead of the falling edge of the
SPICLK signal and receives data on the falling edge of the SPICLK signal. 总结：