蓝桥杯电子赛蓝桥板集成系统（库）源码+项目说明.zip

#include "common.h" #define DELAY_TIME 5 /** 定义I2C总线时钟线和数据线 */ sbit scl = P2^0; sbit sda = P2^1; uint8_t adc_value; /** * @brief I2C总线中一些必要的延时 * * @param[in] i - 延时时间调整. * @return none */ void i2c_delay(unsigned char i) { do { _nop_(); } while(i--); } /** * @brief 产生I2C总线启动条件. * * @param[in] none * @param[out] none * @return none */ void i2c_start(void) { sda = 1; scl = 1; i2c_delay(DELAY_TIME); sda = 0; i2c_delay(DELAY_TIME); scl = 0; } /** * @brief 产生I2C总线停止条件 * * @param[in] none * @param[out] none. * @return none */ void i2c_stop(void) { sda = 0; scl = 1; i2c_delay(DELAY_TIME); sda = 1; i2c_delay(DELAY_TIME); } /** * @brief I2C发送一个字节的数据 * * @param[in] byt - 待发送的字节 * @return none */ void i2c_sendbyte(unsigned char byt) { unsigned char i; // EA = 0; for(i=0; i<8; i++){ scl = 0; i2c_delay(DELAY_TIME); if(byt & 0x80){ sda = 1; } else{ sda = 0; } i2c_delay(DELAY_TIME); scl = 1; byt <<= 1; i2c_delay(DELAY_TIME); } EA = 1; // scl = 0; } /** * @brief 等待应答 * * @param[in] none * @param[out] none * @return none */ unsigned char i2c_waitack(void) { unsigned char ackbit; scl = 1; i2c_delay(DELAY_TIME); ackbit = sda; //while(sda); //wait ack scl = 0; i2c_delay(DELAY_TIME); return ackbit; } /** * @brief I2C接收一个字节数据 * * @param[in] none * @param[out] da * @return da - 从I2C总线上接收到得数据 */ unsigned char i2c_receivebyte(void) { unsigned char da; unsigned char i; // EA = 0; for(i=0;i<8;i++){ scl = 1; i2c_delay(DELAY_TIME); da <<= 1; if(sda) da |= 0x01; scl = 0; i2c_delay(DELAY_TIME); } EA = 1; // return da; } /** * @brief 发送应答 * * @param[in] ackbit - 设定是否发送应答 * @return - none */ void i2c_sendack(unsigned char ackbit) { scl = 0; sda = ackbit; //0：发送应答信号；1：发送非应答信号 i2c_delay(DELAY_TIME); scl = 1; i2c_delay(DELAY_TIME); scl = 0; sda = 1; i2c_delay(DELAY_TIME); } /** * @brief 读写操作过程中一些必要的延时 * * @param[in] i - 指定延时时间 * @return - none */ void operate_delay(unsigned char t) { unsigned char i; while(t--){ for(i=0; i<112; i++); } } #ifdef EEPROM_AT24C02 /** EEPROM AT24C02操作函数 */ /** * @brief 向AT24C02(add)中写入数据val * * @param[in] add - AT24C02存储地址 * @param[in] val - 待写入AT24C02相应地址的数据 * @return - none */ void write_eeprom(unsigned char add,unsigned char val) { i2c_start(); i2c_sendbyte(0xa0); i2c_waitack(); i2c_sendbyte(add); i2c_waitack(); i2c_sendbyte(val); i2c_waitack(); i2c_stop(); operate_delay(10); } /** * @brief 从AT24C02(add)中读出数据da * * @param[in] add - AT24C02存储地址 * @param[out] da - 从AT24C02相应地址中读取到的数据 * @return - da */ unsigned char read_eeprom(unsigned char add) { unsigned char da; i2c_start(); i2c_sendbyte(0xa0); i2c_waitack(); i2c_sendbyte(add); i2c_waitack(); i2c_start(); i2c_sendbyte(0xa1); i2c_waitack(); da = i2c_receivebyte(); i2c_sendack(0); i2c_stop(); return da; } #endif #ifdef ADC_PCF8591 /** ADC芯片PCF8591操作函数 */ /** * @brief PCF8591初始化 * * @param[in] none * @param[out] none * @return none */ void init_pcf8591(uint8_t object) { i2c_start(); i2c_sendbyte(0x90); i2c_waitack(); i2c_sendbyte(object); //ADC通道3 i2c_waitack(); i2c_stop(); operate_delay(10); } /** * @brief 通过I2C总线读取ADC结果 * * @param[in] none * @param[out] temp - AD转换结果 * @return - temp */ unsigned char adc_pcf8591(void) { unsigned char temp; i2c_start(); i2c_sendbyte(0x91); i2c_waitack(); temp = i2c_receivebyte(); i2c_sendack(1); i2c_stop(); return temp; } void READ_ADC(void) { if(MIS_ADC) { MIS_ADC = 0; adc_value = adc_pcf8591(); } } #endif