why 3-wire spi have 4-prot ??

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originally posted by badomen@Nov 10 2006, 11:47 PM

you should get four signals at the top level:

sclk (serial clock)

mosi (master out slave in) --> so if you use a spi master in sopc builder this is your serial output

miso (master in slave out) --> so if you use a spi master in sopc builder this is your serial input

ss/ss_n (slave select)

so if the component you are trying to talk to can only do reads for example you don't need to use the mosi signal (your component can't do anything with the data).

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sopc builder shows only 3 pins either for master or slave how can we include the 4th pin as in the spi protocol.

thanks in advance.