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SPI Help

Topic last updated 21 May 2010, by Barry Shonbeck. 2 replies
Barry Shonbeck
20 May 2010

Does the SPI data get clocked out LSB or MSB first.  The user manual for the 1768 states it can be setup either way but I can't find a reference to this in any of the mbed docs.

Thanks,

bshonbeck

Jon Ward
21 May 2010

The mbed library actually uses the SSP0/1 blocks for the SPI, which don't have the luxury of changing bit order. The data gets clocked out MSB first. If you do use the SPI block block yourself, MSB first is the default behaviour (bit 6 of S0SPCR resets to 0).

Barry Shonbeck
21 May 2010

Thanks Jon,

This is a great help.

Barry