usart.zip_pdc收发

/*---------------------------------------------------------------------------- * Copyright ◎ 2011，Dian团队激光测距组 * All rights reserved. * 文件名称： usart.c * 文件用途： 串口功能检测 *----------------------------------------------------------------------------*/ #include "AT91SAM7A3.h" //定义PDC AT91PS_PDC u_pPDC0 = AT91C_BASE_PDC_US0; AT91PS_PDC u_pPDC1 = AT91C_BASE_PDC_US1; AT91PS_PDC u_pPDC2 = AT91C_BASE_PDC_DBGU; unsigned char a[10]; void delay() { unsigned int i; for(i=0;i<400000;i++); } void sendchar0(unsigned char ch)//最基本的发送函数 { while (!(*AT91C_US0_CSR&AT91C_US_TXRDY)==1); *AT91C_US0_THR = ((ch & 0x1FF));//和0x1FF取与，只保留低8位 } void sendchar1(unsigned char ch)//最基本的发送函数 { while (!(*AT91C_US1_CSR&AT91C_US_TXRDY)==1); *AT91C_US1_THR = ((ch & 0x1FF));//和0x1FF取与，只保留低8位 } void sendchar2(unsigned char ch)//最基本的发送函数 { while (!(*AT91C_US2_CSR&AT91C_US_TXRDY)==1); *AT91C_US2_THR = ((ch & 0x1FF));//和0x1FF取与，只保留低8位 } void sendcharD(unsigned char ch)//最基本的发送函数 { while (!(*AT91C_DBGU_CSR&AT91C_US_TXRDY)==1); *AT91C_DBGU_THR = ((ch & 0x1FF));//和0x1FF取与，只保留低8位 } __irq void irq_in(void) { { int i; *AT91C_PIOB_CODR|=(AT91C_PIO_PB0); delay(); *AT91C_PIOB_SODR|=(AT91C_PIO_PB0); delay(); for(i=0;i<10;i++) sendchar1(a[i]); while((*AT91C_US1_CSR&AT91C_US_RXRDY)); *AT91C_US1_RCR = 10; *AT91C_AIC_EOICR=0x01; } } void init(void) { //*AT91C_PIOA_PER = 0xffffffff; //设置为POIO *AT91C_PIOA_IFER = 0xffffffff; //打开虑波 AT91C_AIC_SVR[AT91C_ID_US1]=(unsigned long) *irq_in;//把中断函数的地址赋给源向量寄存器 //AT91C_AIC_SMR[AT91C_ID_PIOA]=0x01<<5;//对源状态寄存器赋值,以确定触发方式 *AT91C_PIOB_OER=(AT91C_PIO_PB0); *AT91C_PIOB_SODR|=AT91C_PIO_PB0; //初始化led *AT91C_PMC_PCER = 1<<2; //打开外设A时钟 *AT91C_PIOA_IER = 1<<7; *AT91C_AIC_ICCR = 1<<AT91C_ID_US1; //清除中断 *AT91C_AIC_IECR = 1<<AT91C_ID_US1; //打开ＡＩＣ中断 while(*AT91C_PIOA_ISR); *AT91C_US1_IER = AT91C_US_ENDRX; } //时钟频率的初始化 void InitFrec(void) { //Watchdog Disable看门狗关闭 AT91C_BASE_WDTC->WDTC_WDMR= AT91C_WDTC_WDDIS; //设置启动时间 *AT91C_PMC_MOR = (( AT91C_CKGR_OSCOUNT & (0x06 <<8) | AT91C_CKGR_MOSCEN )); //等待主振荡器稳定 while(!(*AT91C_PMC_SR & AT91C_PMC_MOSCS)); //配置PLL *AT91C_PMC_PLLR = ((AT91C_CKGR_DIV & 5) | (AT91C_CKGR_PLLCOUNT & (28<<8)) | (AT91C_CKGR_MUL & (25<<16))); // 等待开始时间 while(!(*AT91C_PMC_SR & AT91C_PMC_LOCK)); while(!(*AT91C_PMC_SR & AT91C_PMC_MCKRDY)); //选择主时钟 //选择预分频数 *AT91C_PMC_MCKR = AT91C_PMC_CSS_PLL_CLK | AT91C_PMC_PRES_CLK_2 ; //等待主时钟就绪 while(!(*AT91C_PMC_SR & AT91C_PMC_MCKRDY)); } void InitUSART0(void)//初始化串口函数 { *AT91C_PIOA_PDR/*PIO禁用寄存器*/ |= AT91C_PIO_PA2 | AT91C_PIO_PA3; //Disables the PIO from controlling the corresponding pin (enables peripheral control of the pin). *AT91C_PIOA_ASR/*外设A 选择寄存器*/ |= AT91C_PIO_PA2 | AT91C_PIO_PA3; //Assigns the I/O line to the Peripheral A function. //使能外设时钟 *AT91C_PMC_PCER = 1<<AT91C_ID_US0; //*AT91C_PMC_PCER = 1<<AT91C_ID_US1; *AT91C_US0_BRGR = 26; //((47923200)/9600x16) //fosc=18432000MHz //配置发送器时间保障寄存器 *AT91C_US0_TTGR/*发送器时间保障寄存器*/ = 0; //设置串口模式 *AT91C_US0_MR = 0x08c0; //Enable the RX and TX PDC transfer requests u_pPDC0->PDC_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN; //Enable usart *AT91C_US0_CR/*控制寄存器*/ = 0x50; *AT91C_US0_RPR = (unsigned long)a; *AT91C_US0_RCR = 10; } void InitUSART1(void)//初始化串口1函数 { *AT91C_PIOA_PDR/*PIO禁用寄存器*/ |= AT91C_PIO_PA7| AT91C_PIO_PA8; *AT91C_PIOA_ASR/*外设A 选择寄存器*/ |= AT91C_PIO_PA7| AT91C_PIO_PA8; //使能外设时钟 *AT91C_PMC_PCER = 1<<AT91C_ID_US1; *AT91C_US1_BRGR = 26; //((47923200)/9600x16) //fosc=18432000MHz //配置发送器时间保障寄存器 *AT91C_US1_TTGR/*发送器时间保障寄存器*/ = 0; //设置串口模式 *AT91C_US1_MR = 0x08c0; //Enable the RX and TX PDC transfer requests u_pPDC1->PDC_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN; //Enable usart *AT91C_US1_CR/*控制寄存器*/ = 0x50; *AT91C_US1_RPR = (unsigned long)a; *AT91C_US1_RCR = 10; } void InitUSART2(void)//初始化串口1函数 { *AT91C_PIOA_PDR/*PIO禁用寄存器*/ |= AT91C_PIO_PA9| AT91C_PIO_PA10; *AT91C_PIOA_ASR/*外设A 选择寄存器*/ |= AT91C_PIO_PA9| AT91C_PIO_PA10; //使能外设时钟 *AT91C_PMC_PCER = 1<<AT91C_ID_US2; *AT91C_US2_BRGR = 26; //((47923200)/9600x16) //fosc=18432000MHz //配置发送器时间保障寄存器 *AT91C_US2_TTGR/*发送器时间保障寄存器*/ = 0; //设置串口模式 *AT91C_US2_MR = 0x08c0; //Enable the RX and TX PDC transfer requests u_pPDC2->PDC_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN; //Enable usart *AT91C_US2_CR/*控制寄存器*/ = 0x50; } void InitUSARTD(void)//初始化串口2函数 { *AT91C_PIOA_PDR/*PIO禁用寄存器*/ |= AT91C_PIO_PA30| AT91C_PIO_PA31; //Disables the PIO from controlling the corresponding pin (enables peripheral control of the pin). *AT91C_PIOA_ASR/*外设A 选择寄存器*/ |= AT91C_PIO_PA30| AT91C_PIO_PA31; //Assigns the I/O line to the Peripheral A function. //使能外设时钟 //*AT91C_PMC_PCER = 1<<DBGU_CIDR; *AT91C_DBGU_BRGR = 26; //((47923200)/9600x16) //fosc=18432000MHz //配置发送器时间保障寄存器 //设置串口模式 *AT91C_DBGU_MR = 0x08c0; //Enable the RX and TX PDC transfer requests u_pPDC2->PDC_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN; //Enable usart *AT91C_DBGU_CR/*控制寄存器*/ = 0x50; } int main() { delay(); InitFrec(); InitUSART0(); InitUSART1(); InitUSART2(); InitUSARTD(); init(); while(1) { sendchar0('A'); delay(); sendchar1('B'); delay(); sendchar2('C'); delay(); sendcharD('D'); delay(); } return 0; }