#include "msp430x54x.h"
void UCS_Init(void) { P5SEL |= 0x0C; // Port select XT2 UCSCTL6 &= ~ XT2OFF; // Set XT2 On P7SEL |= 0x03; // 端口选择外部低频晶振XT1 UCSCTL6 &=~XT1OFF; // 使能外部晶振 UCSCTL6 |= XCAP_3; // 设置内部负载电容 UCSCTL3 |= SELREF_2; // Oref = REFO UCSCTL4 |= SELA_0; // ACLK = XT1 __bis_SR_register(SCG0); // 关闭FLL控制回路 UCSCTL0 =DCO0 + DCO1 + DCO2 + DCO3 + DCO4; // 设置DCOx, MODx UCSC = DCORSEL_5; // 设置DCO振荡范围 UCSCTL2 = FLLD__1 + 0X2A7; // Fdco = ( FLL_FACTOR + 1)×FLLRef = (649 + 1) * 32768 = 21.2992MHz __bic_SR_register(SCG0); // 打开FLL控制回路 __delay_cycles(1024000); do { UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + XT1HFOFFG + DCOFFG); // 清除 XT2,XT1,DCO 错误标志 SFRIFG1 &= ~OFIFG; }while(SFRIFG1&OFIFG); // 检测错误标志 UCSCTL4 |= __XT2CLK + SELM__XT2CLK + SELA__DCOCLKDIV ; // MCLK=LK=晶振12Mhz DCO=21.2922Mhz UCSCTL5 |= DIVS__1; // ACLK=32.768 ,SMCLK=XT2/1,MCLK=XT2 }
void main(void) {unsigned char a,b,c; WDTCTL = WDTPW + WDTHOLD; // Stop WDT UCS_Init(); PEL = 0x30; // P3.4,5 = USCI_A0 TXD/RXD UCA0CTL1 |= UCSWRST; // **Put state machine in reset** UCA0CTL1 |= UCSSEL__ACLK; // SMCLK UCA0BR0 = 184; // 12MHz 115200 (see User's Guide) UCA0BR1 = 0; // 12MHz 115200 UCA0MCTL |= UCBRS_1 + UCBRF_0; // Modulation UCBRSx=1, UCBRFx=0 UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine** UCA0IE |= UCRXIE; // Enable USCI_A0 RX interrupt P1D=0xff; P1OUT=0x55; __bis_SR_register(GIE); //__bis_SR_register(LPM3); // Enter LPM0, interrupts enabled //__no_operation(); // For debugger while(1) {for(a=0;a<250;a++) for(b=0;b<25;b++) for(c=0;c<5;c++) {;} P1OUT=~P1OUT; // UCA0TXBUF=P1OUT; } }
// Echo back RXed character, confirm TX buffer is ready first #pragma vector=USCI_A0_ __interrupt void USCI_A0_ISR(void) { switch(__even_in_range(UCA0IV,4)) { case 0:break; // Vector 0 - no interrupt case 2: // Vector 2 - RXIFG while (!(UCA0IFG&UCTXIFG)); // USCI_A0 TX buffer ready? UCA0TXBUF = UCA0RXBUF; // TX -> RXed character break; case 4:break; // Vector 4 - TXIFG default: break; } }
-电子元器件采购网（www.ruidan.com）是本土元器件目录分销商，采用“小批量、现货、样品”销售模式，致力于满足客户多型号、高质量、快速交付的采购需求。 自建高效智能仓储，拥有自营库存超过50,000种，提供一站式正品现货采购、个性化解决方案、选型替代等多元化服务。