One could use a fourth oscilloscope channel to display a slave-select signal. But because this signal is just a logic-high or logic-low voltage, it can be verified at both ends of the
SPI bus using a standard high-impedance multimeter or logic probe. The oscilloscope then displays the
SPI data and clock signals.
Jan 18, 2017');})();(function(){window.jsl.dh('_Xt5zYPubBdf3-gSC-pPIAg47','
SPI needs three or four-wire for communication ((depends on requirement), MOSI, MISO, SCL, and Chip-select pin. I2C is slower than SPI. In comparison to I2C, SPI is faster. I2C draws more power than SPI.