38 lines
758 B
C
38 lines
758 B
C
#include "spi.h"
|
|
|
|
void spi_select(void)
|
|
{
|
|
CS_PORT&=~(1<<CS_BIT);
|
|
}
|
|
|
|
void spi_deselect(void)
|
|
{
|
|
CS_PORT|=(1<<CS_BIT);
|
|
}
|
|
|
|
unsigned char spi_xchg(unsigned char val)
|
|
{
|
|
SPDR = val;
|
|
while (!(SPSR & (1 << SPIF))) ;
|
|
return SPDR;
|
|
}
|
|
|
|
uint8_t spi_read(){
|
|
return spi_xchg(0x00);
|
|
}
|
|
|
|
void spi_write(uint8_t d){
|
|
spi_xchg(d);
|
|
}
|
|
|
|
void spi_init(){
|
|
CS_PORT |= (1 << CS_BIT); // pull CS pin high
|
|
CS_DDR |= (1 << CS_BIT); // now make it an output
|
|
|
|
SPI_PORT |= (1 << 0); // make sure SS is high
|
|
SPI_DDR = (1 << PORTB2) | (1 << PORTB1) | (1 << PORTB0); // set MOSI, SCK and SS as output, others as input
|
|
SPCR = (1 << SPE) | (1 << MSTR); // enable SPI, master mode 0
|
|
SPCR |= (1 << SPR0) | (0<<SPR1); // div 128
|
|
SPSR |= (0 << SPI2X); // set the clock rate fck/2
|
|
}
|