IIC.rar_i2c_传感器

/**********************按键实验*********************************/ // 公司名称 ：保定飞凌嵌入式技术有限公司 // 描 述 ：按键控制蜂鸣器 // 版 权 ：保定飞凌嵌入式技术有限公司 // 网 址 ：www.witech.com.cn /***************************************************************/ /* 本实验接口说明 */ #include "2440addr.h" /*-----------------------函数声明----------------------------*/ extern void Uart_Printf(char *fmt,...); void Wr24C02(U32 slvAddr,U32 addr,U8 data); void Rd24C02(U32 slvAddr,U32 addr,U8 *data); void Run_IicPoll(void); void IicPoll(void) ; void Delay(int x) ; static U8 iicData[IICBUFSIZE]; static volatile int iicDataCount; static volatile int iicStatus; static volatile int iicMode; static int iicPt; /*------------------------------------------------------------/ 函数名称： iicMain 功能描述： 入口函数 传 参： int count 返 回 值： 无 -------------------------------------------------------------*/ void iicMain(void) { unsigned int i,j; static U8 data[256]; Uart_Printf("IIC Test(Polling) using AT24C02\n"); //设置GPE15->IICSDA 和 GPE14->IICSCL rGPEUP |= 0xc000; //关断上拉 rGPECON &= ~0xf0000000; rGPECON |= 0xa0000000; //GPE15:IICSDA , GPE14:IICSCL //使能ACK, 预分频 IICCLK=PCLK/16, 使能中断, 发送时钟 Tx clock=IICCLK/16 rIICCON = (1<<7) | (0<<6) | (1<<5) | (0xf); rIICADD = 0x10; //2440 从地址 = [7:1] rIICSTAT = 0x10; //IIC总线数据输出使能(Rx/Tx) Uart_Printf("Write test data into AT24C02\n"); //写入一个page的数据，page的大小是256byte， //page 的起始地址是0xa0，写入的数据是：0、1、2、...255。0xa0是AT24C02的页地址。 //AT24C02的页地址是0x00/0x20/0x40/0x60/0x80/0xa0/0xc0/0xe0。 for(i=0;i<256;i++) Wr24C02(0xa0,(U8)i,i); //U32 slvAddr,U32 addr,U8 data for(i=0;i<256;i++) //初始化data数组的值为0。 data[i] = 0; Uart_Printf("Read test data from AT24C02\n"); for(i=0;i<256;i++) //读24C02的0xa0地址中数据到data数组中。 Rd24C02(0xa1,(U8)i,&(data[i])); for(i=0;i<16;i++) //输出data数组接收数据的值 { for (j=0;j<16;j++) Uart_Printf("%2x ",data[i*16+j]); Uart_Printf("\n"); } Uart_Printf("OK! Write data is same to Read data!\n"); while(1); } /*------------------------------------------------------------/ 函数名称： Wr24C02 功能描述： 写24c02 传 参： U32 slvAddr,U32 addr,U8 data 返 回 值： 无 -------------------------------------------------------------*/ void Wr24C02(U32 slvAddr,U32 addr,U8 data) { iicMode = WRDATA; iicPt = 0; iicData[0] = (U8)addr; iicData[1] = data; iicDataCount = 2; //8-bit data shift register for IIC-bus Tx/Rx operation. rIICDS = slvAddr; //0xa0 //Master Tx mode, Start(Write), IIC-bus data output enable //Bus arbitration sucessful, Address as slave status flag Cleared, //Address zero status flag cleared, Last received bit is 0 rIICSTAT = 0xf0; //Clearing the pending bit isn't needed because the pending bit has been cleared. while(iicDataCount!=-1) Run_IicPoll(); iicMode = POLLACK; while(1) { rIICDS = slvAddr; iicStatus = 0x100; //To check if _iicStatus is changed rIICSTAT = 0xf0; //Master Tx, Start, Output Enable, Sucessful, Cleared, Cleared, 0 rIICCON = 0xe0;//0xaf; //Resumes IIC operation. //hzh while(iicStatus==0x100) Run_IicPoll(); if(!(iicStatus & 0x1)) break; //When ACK is received } rIICSTAT = 0xd0; //Master Tx condition, Stop(Write), Output Enable rIICCON = 0xe0;//0xaf; //Resumes IIC operation. //hzh Delay(1); //Wait until stop condtion is in effect. } /*------------------------------------------------------------/ 函数名称： Rd24C02 功能描述： 读24c02 传 参： U32 slvAddr,U32 addr,U8 *data 返 回 值： 无 -------------------------------------------------------------*/ void Rd24C02(U32 slvAddr,U32 addr,U8 *data) { iicMode = SETRDADDR; iicPt = 0; iicData[0] = (U8)addr; iicDataCount = 1; rIICDS = slvAddr; rIICSTAT = 0xf0; //MasTx,Start //Clearing the pending bit isn't needed because the pending bit has been cleared. while(iicDataCount!=-1) Run_IicPoll(); iicMode = RDDATA; iicPt = 0; iicDataCount = 1; rIICDS = slvAddr; rIICSTAT = 0xb0; //主接收开始 rIICCON = 0xe0; //Resumes IIC operation. while(iicDataCount!=-1) Run_IicPoll(); *data = iicData[1]; } /*------------------------------------------------------------/ 函数名称： Run_IicPoll 功能描述： 传 参： 无 返 回 值： 无 -------------------------------------------------------------*/ void Run_IicPoll(void) { if(rIICCON & 0x10) //Tx/Rx Interrupt Enable IicPoll(); } /*------------------------------------------------------------/ 函数名称： IicPoll 功能描述： 传 参： 无 返 回 值： 无 -------------------------------------------------------------*/ void IicPoll(void) { U32 iicSt,i; iicSt = rIICSTAT; if(iicSt & 0x8){}; //When bus arbitration is failed. 总线仲裁失败 if(iicSt & 0x4){}; //When a slave address is matched with IICADD if(iicSt & 0x2){}; //When a slave address is 0000000b if(iicSt & 0x1){}; //When ACK isn't received switch(iicMode) { case POLLACK: iicStatus = iicSt; break; case RDDATA: if((iicDataCount--)==0) { iicData[iicPt++] = rIICDS; rIICSTAT = 0x90; //Stop MasRx condition rIICCON = 0xe0; //Resumes IIC operation. Delay(1); //Wait until stop condtion is in effect. //Too long time... //The pending bit will not be set after issuing stop condition. break; } iicData[iicPt++] = rIICDS; //The last data has to be read with no ack. if((iicDataCount)==0) rIICCON = 0x60;//0x2f; //Resumes IIC operation with NOACK. else rIICCON = 0xe0;//0xaf; //Resumes IIC operation with ACK break; case WRDATA: if((iicDataCount--)==0) { rIICSTAT = 0xd0; //stop MasTx condition rIICCON = 0xe0;//0xaf; //resumes IIC operation. Delay(1); //wait until stop condtion is in effect. //The pending bit will not be set after issuing stop condition. break; } rIICDS = iicData[iicPt++]; //_iicData[0] has dummy. for(i=0;i<10;i++); //for setup time until rising edge of IICSCL rIICCON = 0xe0;//0xaf; //resumes IIC operation. break; case SETRDADDR: if((iicDataCount--)==0) break; //IIC operation is stopped because of IICCON[4] rIICDS = iicData[iicPt++]; for(i=0;i<10;i++); //for setup time until rising edge of IICSCL rIICCON = 0xe0;//0xaf; //resumes IIC operation. break; default: break; } } /*------------------------------------------------------------/ 函数名称： Delay 功能描述： 延时函数 传 参： int x 返 回 值： 无 -------------------------------------------------------------*/ void Delay(int x) { int k, j; while(x) { for (k=0;k<=0xff;k++) for(j=0;j<=0xff;j++); x--; } }