# P9_18 (SPI0_D1 => MOSI) outputs data to peripheral device
# P9_21 (SPIO_DO => MISO) receives data from peripheral device
# P9_22 (SPI0_SCLK => SCLK) outputs clock signal
# P9_18 (SPI0_D1 => MOSI) outputs data to peripheral device
# P9_21 (SPIO_DO => MISO) receives data from peripheral device
# P9_22 (SPI0_SCLK => SCLK) outputs clock signal