MSP430F149学习之路——SPI

代码一：

 1 //******************************************************************************
 2 //Description:SPI slave talks to SPI master using 3-wire mode. Data is sent
 3 //to the master starting at 0x00 and increments. Received data from the
 4 //master is expected to start at 0xff and decrements with each transmission.
 5 //******************************************************************************
 6 #include <msp430x14x.h>
 7 char MST_data = 0x00,SLV_data = 0XFF;
 8 void main()
 9 {
10   WDTCTL = WDTPW + WDTHOLD;
11
12   P6DIR |= BIT0;
13   P6OUT |= BIT0;
14   P3SEL = 0X0E;                        //P3.1,2,3 SPI option select
15   P3DIR |= BIT1;
16   P3OUT |= BIT1;
17
18   U0CTL |= SWRST + SYNC + MM +CHAR;   //master spi 8-bit
19   U0TCTL |= CKPH + SSEL1 + STC;
20   U0TCTL &= ~CKPL;
21
22   U0BR0 = 0X02;                      //SPICLK = SMCLK/2
23   U0BR1 = 0X00;
24   U0MCTL = 0X00;
25
26   ME1 = USPIE0;
27   U0CTL &= ~SWRST;
28   IE1 |= URXIE0;     //receive enable
29   _EINT();
30
31   while(1)
32   {
33     TXBUF0 = MST_data;
34     LPM0;
35   }
36 }
37 #pragma vector=USART0RX_VECTOR
38 __interrupt void SPI_RX()
39 {
40   P6OUT ^= BIT0;
41   while((IFG1 & UTXIFG0)==0);
42   if(U0RXBUF == SLV_data)
43   {
44     SLV_data = SLV_data - 1;
45     MST_data = MST_data + 1;
46     U0TXBUF  = MST_data;
47   }
48   else
49     TXBUF0 = MST_data;
50 }

代码二：

 1 #include <msp430x14x.h>
 2 char MST_data = 0x00,SLV_data = 0xff;
 3 void main()
 4 {
 5   WDTCTL = WDTPW + WDTHOLD;
 6   P3SEL = 0X0E;
 7   UOCTL = CHAR + SYNC + SWRST;
 8   U0TCTL = CKPL + SSEL1 + STC;
 9   U0CLT &= ~CKPH;
10
11   ME1 |= USPIE0;
12   U0CTL &= ~SWRST;
13   IE1 |= URXIE0;
14   _EINT();
15   while(1)
16   {
17     TXBUF0 = SLV_data;
18     LMP4;
19   }
20 }
21 #pragma vector=USART0RX_VECTOR
22 __interrupt void USART0_RX()
23 {
24   while((IFG1 & OFIFG)==0);
25   if(U0RXBUF == MST_data)
26   {
27     SLV_data = SLV_data - 1;
28     MST_data = MST_data + 1;
29     TXBUF0 = SLV_data;
30   }
31   else
32     TXBUF0 = SLV_data;
33 }