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yishuihan

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求助 msp430g2553与TCA6416用IIC通讯 但中断只能进一次，这是什么原因 #include "msp430g2553.h" void gpio_init (void); void iic_init(void); unsigned char TXData[4]={0x02,0x00,0xa2,0x03}; int i,j; void main(void) { WDTCTL = WDTPW + WDTHOLD; //Close Interal Watchdog Timer i=0; P1DIR |= 0x01; P1OUT&= ~0x01; _EINT(); gpio_init (); iic_init(); UCB0CTL1 |= UCTR + UCTXSTT; // I2C TX, start condition while (1){ } } void gpio_init (void) { P1SEL |= BIT6 + BIT7; // Assign I2C pins to USCI_B0 P1SEL2|= BIT6 + BIT7; // Assign I2C pins to USCI_B0 } void iic_init(void) { UCB0CTL1 |= UCSWRST; // Enable SW reset UCB0CTL0 = UCMST + UCMODE_3 + UCSYNC; // I2C Master, synchronous mode UCB0CTL1 = UCSSEL_2 + UCSWRST+ UCTR; // Use SMCLK, keep SW reset UCB0BR0 = 12; // fSCL = SMCLK/12 = ~100kHz UCB0BR1 = 0; UCB0I2CSA = 0x20; // Slave Address is 020h UCB0CTL1 &= ~UCSWRST; // Clear SW reset, resume operation IE2 |= UCB0TXIE; // Enable TX interrupt } // USCI_B0 Data ISR #pragma vector = USCIAB0TX_VECTOR __interrupt void USCIAB0TX_ISR(void) { UCB0TXBUF = TXData; // TX data P1OUT^=0x01; i=i+1; if(i==4){ UCB0CTL1 |= UCTXSTP; // I2C TX, start condition } }