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I recently started learning and applying the SPI protocol with a OLED display and it's been a good learning experience. The sample code of the display used the SPI Mode1. This made me wonder, if there are specific applications for each of the SPI Modes?

To be more specific, Are any of the 4 SPI Modes (eg: Mode0) more preferred in a specific industry (eg: Automobile industry or Aerospace Industry)? OR

Are any of the SPI modes more preferred in a certain application (eg: display interface or 4-20mA circuits)?

Thank You in advance.

J2018
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I don't think there's any preference. SPI bus never has been formally standardised and it's been around almost forty years. So pretty much every combination of these "modes" have been used by different vendors. Don't think the mode numbers always mean the same thing either.

https://www.byteparadigm.com/applications/introduction-to-i2c-and-spi-protocols/

To make things more interesting there are "nonstandard" implementations, one popular choice is adding a "ready" signal to the slave. SPI was originally designed (in 1979!) to communicate with simple devices which would have guaranteed response times. This can cause problems with more complex devices such as auxiliary microcontrollers or, say, standalone communication modules.

Throw in dual spi (can run in half-duplex mode with 2 bits transferred simultaneously) or quad spi which adds two extra data pins. There are, naturally, different incompatible versions of both.

So that's why you have these different modes, it's because there's no standard and you have to support different behaviors to maximize compatibility.

Barleyman
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  • Thank You @Barleyman for the comments. I didn't know the SPI protocol was so old. – J2018 Jul 26 '18 at 15:17
  • "Don't think the mode numbers always mean the same thing either." Yes to this. My last company swapped modes 1 and 2. It made me crazy. – Annie Jul 26 '18 at 16:20