[FRDM-KL25Z] Kinetis - SPI 테스트
KL25Z SPI 테스트를 위한 자료 정리
SPI Bus clock
Bus clock Up to 50 MHz Up to 4 MHz MCGOUTCLK clock divider
KL25Z SPI 초기화 함수
void SPI0_Init(void)
{
SIM_SCGC5 |= SIM_SCGC5_PORTD_MASK; //Turn on clock to D module
SIM_SCGC4 |= SIM_SCGC4_SPI0_MASK; //Enable SPI0 clock
_SPI0_IO_INIT();
/*
PORTD_PCR0 = PORT_PCR_MUX(0x2); //Set PTD0 to mux 2 [SPI0_PCS0]
PORTD_PCR1 = PORT_PCR_MUX(0x2); //Set PTD1 to mux 2 [SPI0_SCK]
PORTD_PCR2 = PORT_PCR_MUX(0x2); //Set PTD2 to mux 2 [SPI0_MOSI]
PORTD_PCR3 = PORT_PCR_MUX(0x2); //Set PTD3 to mux 2 [SPIO_MISO]
*/
//SPI_C1_CPOL_MASK
//SPI_C1_CPHA_MASK
SPI0_C1 = SPI_C1_MSTR_MASK;// | SPI_C1_SSOE_MASK; //Set SPI0 to Master & SS pin to auto SS
//SPI0_C2 = SPI_C2_MODFEN_MASK; //Master SS pin acts as slave select output
//Set baud rate prescale
SPI0_BR = (SPI_BR_SPPR(0x01) | SPI_BR_SPR(0x02));
//SPI Mode
Cbi(SPI0_C1, SPI_C1_CPOL_MASK);
Cbi(SPI0_C1, SPI_C1_CPHA_MASK);
//Enable SPI0
Sbi(SPI0_C1, SPI_C1_SPE_MASK);
}
KL25Z SPI 데이터 송수신 함수
unsigned char SPI0_WriteReadByte(unsigned char Data)
{
//SPTEF - 1 이면 데이터 전송
while(!(SPI_S_SPTEF_MASK & SPI0_S))
{
asm("nop"); //While buffer is not empty do nothing
}
SPI0_D = Data; //Write char to SPI
//SPRF - 1 이면 데이터 수신
while(!(SPI_S_SPRF_MASK & SPI0_S))
{
asm("nop"); //While buffer is not empty do nothing
}
return SPI0_D;
}
