The SPISettings object is used to configure the SPI port for your SPI device. All 3 parameters are combined to a single SPISettings object, which is given to SPI.beginTransaction().
When all of your settings are constants, SPISettings should be used directly in SPI.beginTransaction(). See the syntax section below. For constants, this syntax results in smaller and faster code.
If any of your settings are variables, you may create a SPISettings object to hold the 3 settings. Then you can give the object name to SPI.beginTransaction(). Creating a named SPISettings object may be more efficient when your settings are not constants, especially if the maximum speed is a variable computed or configured, rather than a number you type directly into your sketch.
SPI.beginTransaction(SPISettings(14000000, MSBFIRST, SPI_MODE0))
Note: Best if all 3 settings are constants
SPISettings mySettting(speedMaximum, dataOrder, dataMode)
Note: Best when any setting is a variable''
speedMaximum: The maximum speed of communication. For a SPI chip rated up to 20 MHz, use 20000000.
dataOrder: MSBFIRST or LSBFIRST
dataMode : SPI_MODE0, SPI_MODE1, SPI_MODE2, or SPI_MODE3
Corrections, suggestions, and new documentation should be posted to the Forum.
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