SPI Questions

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All,
What's the difference between SPI mode 0 and 3? How do I translate that into a setup difference in the code?

I believe pullup resistors are required for the SI, SO, and CS lines, correct? If so, what is the largest ohm resistor I can use (to limit current leakage)? I assume this is a function of bus frequency. I will be no faster than 4 Mhz and am running 3.3v.

Thanks!
Jon

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Hi Jon,
the difference between the 4 modes are
1. the idle-line of sck
2. the rising or falling edge to read/write SI/SO

My experience of pull-up:
only for the input-pins 10k and you don't have any problem;
my boards are running with 8MHz,5V
the SPI is running with500kHz

bye
Michael

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