uint8_t spi_send_rcv(uint8_t data)
{
uint8_t i,temp;
temp = 0;
clk(0);
for(i=0; i<8; i++)
{
if(data & 0x80)
{
mosi(1);
}
else mosi(0);
data <<= 1;
clk(1);
_nop_();
_nop_();
temp <<= 1;
if(miso())temp++;
clk(0);
_nop_();
_nop_();
}
return temp;
}
void SPI::begin() {
OutputPin sck(SPI_SCK_PORT, SPI_SCK_PIN);
OutputPin mosi(SPI_MOSI_PORT, SPI_MOSI_PIN);
InputPin miso(SPI_MISO_PORT, SPI_MISO_PIN);
OutputPin ss(SPI_SS_PORT, SPI_SS_PIN);
sck.begin();
mosi.begin();
miso.begin();
ss.begin();
sck.clear();
mosi.clear();
ss.set();
// Warning: if the SS pin ever becomes a LOW INPUT then SPI
// automatically switches to Slave, so the data direction of
// the SS pin MUST be kept as OUTPUT.
SPCR = (1<<MSTR) | (1<<SPE);
}
