sd library 1.1.1 new begin(clock, pin) max clock ?

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hi.

new version of sd library introduce sd.begin(clock, pin) function.

i want know should maximum clock value possible, uno or due example ?

regards.

nitrof

they have not updated sd library documentation since sd uses spi guess value passed spi library.  the spi library calculates available clock divider give highest clock below specified limit.  i think intended specify maximum rate of spi interface of sd card.  if not specified value of 4 mhz (the default spi).  the uno can go 8 mhz. 

for more detail, see library source code.


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