SPI only supports 8bit or 9bit?

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pmmccorkell
 
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SPI only supports 8bit or 9bit?

Post by pmmccorkell »

Hello again.
This topic was locked, but the issue persists.
viewtopic.php?f=60&t=184861

The suggestion of using 2x 8bit SPI is not working.
I have working code on LPC1768 using MBed compiler (C++ like), using 16bit SPI.
It does not play nice with that device if I switch back to 8bit SPI either.

The provided solution is not functional, and I suspect the issue is the significant delay between the 8bit words. Observed 12.4us delay between the 2 8bit pieces.
It would be really really nice if we could use more than the default 8/9 bits on a microcontroller that is perfectly capable of going up to 16 bits.

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pmmccorkell
 
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Re: SPI only supports 8bit or 9bit?

Post by pmmccorkell »

Disregard, I'm an idiot and missed the CPHA = 1 in the datasheet.
Everything works now, excited to ditch these old LPC1768s!

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