www.pudn.com > 149spi.rar > spi.c

 
#include   
 
void main(void) 
{ 
  volatile unsigned int i; 
 
  WDTCTL = WDTPW + WDTHOLD;                 // Stop watchdog 
  P1OUT = 0x00;                             // P1.0 setup for LED output 
  P1DIR |= 0x03; 
  P5SEL |= 0x0E;                            // P5.1,2,3 SPI option select 
  P5OUT &= ~0x01; 
  P5DIR |= 0x01;                            //Reset Slave 
  P5DIR &= ~0x01; 
  U1CTL = CHAR + SYNC + MM + SWRST;         // 8-bit, SPI, Master 
  U1TCTL = CKPL + SSEL1 + STC;              // Polarity, SMCLK, 3-wire 
  U1BR0 = 0x02;                             // SPICLK = SMCLK/2 
  U1BR1 = 0x00; 
  U1MCTL = 0x00; 
  ME2 |= USPIE1;                            // Module enable 
  U1CTL &= ~SWRST;                          // SPI enable 
  IE2 |= URXIE1 + UTXIE1;                   // RX and TX interrupt enable 
 
  for (i = 0xFFF; i > 0; i--);              // Time for slave to ready 
  _BIS_SR(LPM0_bits + GIE);                 // Enter LPM0 w/ interrupt 
} 
 
#pragma vector=USART1RX_VECTOR 
__interrupt void SPI1_rx (void) 
{ 
  P1OUT = RXBUF1;                           // RXBUF1 to TXBUF1 
} 
 
#pragma vector=USART1TX_VECTOR 
__interrupt void SPI1_tx (void) 
{ 
  unsigned int i; 
 
  i = P1IN; 
  i = i >> 4; 
  TXBUF1 = i;                               // Transmit character 
}