CTD107蓝桥杯555方波计数器&&超声波测距

/* 程序说明: IIC总线驱动程序 软件环境: Keil uVision 4.10 硬件环境: CT107单片机综合实训平台 8051，12MHz 日 期: 2011-8-9 */ #include "iic.h" #define DELAY_TIME 5 #define SlaveAddrW 0xA0 #define SlaveAddrR 0xA1 //总线引脚定义 sbit SDA = P2^1; /* 数据线 */ sbit SCL = P2^0; /* 时钟线 */ void IIC_Delay(unsigned char i) { do{_nop_();} while(i--); } //总线启动条件 void IIC_Start(void) { SDA = 1; SCL = 1; IIC_Delay(DELAY_TIME); SDA = 0; IIC_Delay(DELAY_TIME); SCL = 0; } //总线停止条件 void IIC_Stop(void) { SDA = 0; SCL = 1; IIC_Delay(DELAY_TIME); SDA = 1; IIC_Delay(DELAY_TIME); } //发送应答 void IIC_SendAck(bit ackbit) { SCL = 0; SDA = ackbit; // 0：应答，1：非应答 IIC_Delay(DELAY_TIME); SCL = 1; IIC_Delay(DELAY_TIME); SCL = 0; SDA = 1; IIC_Delay(DELAY_TIME); } //等待应答 bit IIC_WaitAck(void) { bit ackbit; SCL = 1; IIC_Delay(DELAY_TIME); ackbit = SDA; SCL = 0; IIC_Delay(DELAY_TIME); return ackbit; } //通过I2C总线发送数据 void IIC_SendByte(unsigned char byt) { unsigned char i; for(i=0; i<8; i++) { SCL = 0; IIC_Delay(DELAY_TIME); if(byt & 0x80) SDA = 1; else SDA = 0; IIC_Delay(DELAY_TIME); SCL = 1; byt <<= 1; IIC_Delay(DELAY_TIME); } SCL = 0; } //从I2C总线上接收数据 unsigned char IIC_RecByte(void) { unsigned char i, da; for(i=0; i<8; i++) { SCL = 1; IIC_Delay(DELAY_TIME); da <<= 1; if(SDA) da |= 1; SCL = 0; IIC_Delay(DELAY_TIME); } return da; }