本帖最后由 shuishuo615 于 2013-10-15 10:23 编辑
东拼西凑了下代码，
读ADS1115 的转换数据16位,MSB+LSB
调试现象：debug串口用watch功能 第一次while（1）的数据有问题，第二次以后进while读出正常。
比如接了3v 在ain端口，第一次while出来的数据ConversionResult是0x3eff,第二进while次才是0x3e80为正确值。我是在最后一句程序处设置断点查看的。估计是不是在读完MSB后的操作不正确？反正第一次读LSB总是0xff，第二次就对了。。。。。附上程序，只有一个main.c
附上ADS的读数据时序
/**
******************************************************************************
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm8s.h"
/* Private defines -----------------------------------------------------------*/
#define ADS1115_ADDR 0x90
#define ADS1115_POINT_CONFIG_REG 0x01
#define ADS1115_POINT_CONVERSION_REG 0x00
/* Private function prototypes -----------------------------------------------*/
u8 AD_MSB,AD_LSB;
u16 ConversionResult;
/* Private functions ---------------------------------------------------------*/
void main(void)
{
//void bsp_InitI2C(void)
{
I2C->CR1 = 0x00; //禁用I2C模块 以初始化I2C模块
I2C->CR2 = 0x04; //应答使能
I2C->FREQR = 10; //输入时钟频率 10M
I2C->OARH = 0x40; //设置地址模式配置 为1
I2C->OARL = 0x00; //做为从机时的7位地址
I2C->ITR = 0x00; //禁止所有的I2C中断
I2C->CCRH = 0x80; //快速模式I2C 快速模式 tlow/thigh = 2;
I2C->CCRL = 12; //400Khz 时钟速率
I2C->CR1 = 0x01; //启用I2C模块
}
// void ADS1115_Init(void)
{
unsigned char Temp;
I2C->CR2 |= 0x01; //产生始起信号
while((I2C->SR1&0x01)==0); //等待始起信号已发送
I2C->DR = ADS1115_ADDR;
while((I2C->SR1&0x02)==0); //等待接收到从ADS1115返回的ACK
Temp = I2C->SR1;
Temp = I2C->SR3; //读SR3寄存器，以清除标志位ADDR
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->DR = ADS1115_POINT_CONFIG_REG;
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->DR = 0x52; //MSB
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->DR = 0x83; //LSB
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->CR2 |= 0x02; //产生停止信号
}
/* Infinite loop */
while (1)
{
//u16 ADS1115_Read_Conversion(void)
{
unsigned char Temp;
/*********************************************
将寄存器指向读取转换结果寄存器0x00
**********************************************/
while(I2C->SR3 & 0x02); //等待总线空闲
I2C->CR2 |= 0x01; //产生始起信号
while((I2C->SR1&0x01)==0); //等待始起信号已发送
I2C->DR = ADS1115_ADDR;
while((I2C->SR1&0x02)==0); //等待接收到从ADS1115返回的ACK
Temp = I2C->SR1;
Temp = I2C->SR3; //读SR3寄存器，以清除标志位ADDR
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->DR = ADS1115_POINT_CONVERSION_REG;
while((I2C->SR1&0x80)==0); //等待数据寄存器空
I2C->CR2 |= 0x02; //产生停止信号
/*************************************************
开始分别读取高8位和低8位
**************************************************/
//1.产生I2C始起信号
while(I2C->SR3 & 0x02); //等待总线空闲
I2C->CR2 |= 0x01; //产生始起信号
while((I2C->SR1&0x01)==0); //等待始起信号已发送
//发送ADS1115器件地址+读操作
I2C->DR = ADS1115_ADDR+0x01;
while((I2C->SR1&0x02)==0); //等待接收到从ADS1115返回的ACK
Temp = I2C->SR1; //读SR3寄存器，以清除标志位ADDR
Temp = I2C->SR3; //读SR3寄存器，以清除标志位ADDR
/*1115返回数据*/
/*读高8位数据*/
while((I2C->SR1&0x40)==0); //等待数据寄存器不为空BTF
Temp = I2C->SR1; //读SR1寄存器，以清除标志位ADDR
AD_MSB=0x00;
AD_MSB=I2C->DR ;
Temp = I2C->SR3; //读SR3寄存器，以清除标志位ADDR
I2C->CR2 &= ~0x04;
I2C->CR2 |= 0x02;
/*读低8位数据*/
while((I2C->SR1&0x40)==0); //等待数据寄存器不为空
Temp = I2C->SR1;
AD_LSB=0x00;
AD_LSB=I2C->DR ;
Temp = I2C->SR3; //读SR3寄存器，以清除标志位ADDR
I2C->CR2 |= 0x04;
I2C->CR2 &= ~0x08;
/*计算转换结果*/
ConversionResult = 0x0000;
ConversionResult += AD_MSB;
ConversionResult = ConversionResult<<8;
ConversionResult += AD_LSB;
// return ConversionResult;
}
}
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval : None
*/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif
/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/
|
|
楼主
