def set_mode(self,mode):
if mode < <NUM_LIT:0> or mode > <NUM_LIT:3>:<EOL><INDENT>raise ValueError('<STR_LIT>')<EOL><DEDENT>self._device.mode(mode)<EOL>
Set SPI mode which controls clock polarity and phase.  Should be a
        numeric value 0, 1, 2, or 3.  See wikipedia page for details on meaning:
        http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus