Topic: SPI wierdness
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Engineer by day, hobbyist by night. WA2SKO since 1973.
Jan 16, 2013, 09:02 pm
I just converted a graphics display driver from SPI bit-bang to hardware SPI. Works fine.
Strange thing though... it works REGARDLESS of which SPI mode I use!
The datasheet for the graphics device shows transfers on the rising edge of SCK and SCK idle mode is logic 1 which means "SPI Mode 3" (and mode 3 works).
But, modes 0 thru 2 ALSO work?
What the heck is going on here? Any ideas?
may prefer Blondes, but
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Re: SPI wierdness
Jan 16, 2013, 09:21 pm
I suspect that as long as the data is stable when SCK goes from low to high it gets clocked in okay.
So, 0000000011111000000 works,
and 1111000011111111111 works
| as long as the data is done changing by here
Designing & building electrical circuits for over 25 years. Screw Shield for Mega/Due/Uno, Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at my website.