HTS221和其它几款数字温湿度传感器数据对比

littleshrimp · 发表于 2017-11-11 00:43

HTS221和其它几款数字温湿度传感器数据对比 [复制链接]

HTS221是ST公司的一款数字温湿度传感器，手册上标称的湿度精度是±3.5%RH（在20%~80%范围内）温度精度是±0.5℃（在15℃~40℃范围内），今天我拿HTS221分别和TI的HDC1080、SILABS的SI7051、SI7021、sensirion的SHT21这几款数字温湿度传感器做了对比

传感器合照

因为条件有限，测试的方法是将HTS221分别和其它传感器两两装进一个纸盒，传感器尽量接近，高度尽量相同

HTS221的Outputdata设置为1Hz, 温度AVGT设置成256

每8秒钟采集一次HTS221和其它传感器数据，然后通过串口发送给PC

下面是HTS221和其它传感器的温湿度数据对比

1.HTS221和SI7051温度对比

2.HTS221和SI7021的温度数据

3.HTS221和SHT21温度对比

4.HTS221和SHT21湿度对比

5.HTS221和SHT21湿度对比 (另一片SHT21)

6.HTS221和HDC1080温度对比

7.HTS221和HDC1080湿度对比

8.HTS221和SI7021湿度对比

上图中蓝色为其它传感器的温湿度数据，橙色为HTS221的温湿度数据

从数据中可以看出HTS221数据的波动比较大，和SI7051对比时温度最大时相差0.184摄氏度

SI7051的标称精度是±0.1摄氏度，单从这个数据来看这颗HTS221的温度精度还是不错的

湿度方面HTS221比2片SHT21湿度最大SHT21高出8.5%rH

比HDC1080最大高出3%rH,比SI7021低2.53%Rh

因为相对湿度和温度的精度有关

湿度方面从这些数据也不好判断谁准谁不准

附上测试代码：

/*
MSP430FR5969
-----------------
| P2.0/UCA0TXD|----> PC
| |
| |
| P2.1/UCA0RXD|<---- PC
| |
SCL --o--|P3.5 |
| |
SDA --o--|P3.6 |
*/
/*******************************************************************************
* * INCLUDES
* */
#include "msp430.h"
#include <stdio.h>
#include <math.h>
#include <stdint.h>
#include "uart.h"
#include "soft_i2c.h"
#include "timer.h"
#include "si7021.h"
/*******************************************************************************
* * MACROS
* */
/*******************************************************************************
* * CONSTANTS
* */
#define HTS221_WHO_AM_I_REG (uint8_t)0x0F
#define HTS221_CTRL_REG1 (uint8_t)0x20
#define HTS221_CTRL_REG2 (uint8_t)0x21
#define HTS221_CTRL_REG3 (uint8_t)0x22
#define HTS221_AV_CONF_REG (uint8_t)0x10
#define HTS221_STATUS_REG (uint8_t)0x27
#define HTS221_HR_OUT_L_REG (uint8_t)0x28
#define HTS221_TEMP_OUT_L_REG (uint8_t)0x2A
#define HTS221_H0_RH_X2 (uint8_t)0x30
#define HTS221_H1_RH_X2 (uint8_t)0x31
#define HTS221_T0_DEGC_X8 (uint8_t)0x32
#define HTS221_T1_DEGC_X8 (uint8_t)0x33
#define HTS221_T0_T1_DEGC_H2 (uint8_t)0x35
#define HTS221_H0_T0_OUT_L (uint8_t)0x36
#define HTS221_H0_T0_OUT_H (uint8_t)0x37
#define HTS221_H1_T0_OUT_L (uint8_t)0x3A
#define HTS221_H1_T0_OUT_H (uint8_t)0x3B
#define HTS221_T0_OUT_L (uint8_t)0x3C
#define HTS221_T0_OUT_H (uint8_t)0x3D
#define HTS221_T1_OUT_L (uint8_t)0x3E
#define HTS221_T1_OUT_H (uint8_t)0x3F
#define HTS221_SLV_ADDRESS (0xbe)
/*******************************************************************************
* * TYPEDEFS
* */
/*******************************************************************************
* * GLOBAL VARIABLES
* */
/*******************************************************************************
* * EXTERNAL VARIABLES
* */
/*******************************************************************************
* * EXTERNAL FUNCTIONS
* */
/*******************************************************************************
* * LOCAL VARIABLES
* */
uint8_t buf[12];
float t[2],h[2];
/*******************************************************************************
* * PROFILE CALLBACKS
* */
/*******************************************************************************
* * LOCAL FUNCTIONS
* */
void dco_init(void);
/*******************************************************************************
* * PUBLIC FUNCTIONS
* */
void delay(int32_t d)
{
while(d--)
{
__delay_cycles(1000);
}
}
float HTS221_Get_Humidity(void)
{
int16_t H0_T0_out, H1_T0_out, H_T_out;
int16_t H0_rh, H1_rh;
uint8_t buffer[2];
float tmp_f;
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_H0_RH_X2 | BIT7, buffer , 2);
H0_rh = buffer[0] >> 1;
H1_rh = buffer[1] >> 1;
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_H0_T0_OUT_L | BIT7, buffer , 2);
H0_T0_out = (((uint16_t)buffer[1]) << 8) | (uint16_t)buffer[0];
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_H1_T0_OUT_L | BIT7, buffer , 2);
H1_T0_out = (((uint16_t)buffer[1]) << 8) | (uint16_t)buffer[0];
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_HR_OUT_L_REG | BIT7, buffer , 2);
H_T_out = (((uint16_t)buffer[1]) << 8) | (uint16_t)buffer[0];
tmp_f = (float)(H_T_out - H0_T0_out) * (float)(H1_rh - H0_rh) / (float)(H1_T0_out - H0_T0_out) + H0_rh;
return tmp_f;
}
float HTS221_Get_Temperature(void)
{
int16_t T0_out, T1_out, T_out, T0_degC_x8_u16, T1_degC_x8_u16;
int16_t T0_degC, T1_degC;
uint8_t buffer[4], tmp;
float tmp_f;
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_T0_DEGC_X8 | BIT7,buffer, 2);
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_T0_T1_DEGC_H2 | BIT7, &tmp,1);
T0_degC_x8_u16 = (((uint16_t)(tmp & 0x03)) << 8) | ((uint16_t)buffer[0]);
T1_degC_x8_u16 = (((uint16_t)(tmp & 0x0C)) << 6) | ((uint16_t)buffer[1]);
T0_degC = T0_degC_x8_u16 >> 3;
T1_degC = T1_degC_x8_u16 >> 3;
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_T0_OUT_L | BIT7, buffer,4);
T0_out = (((uint16_t)buffer[1]) << 8) | (uint16_t)buffer[0];
T1_out = (((uint16_t)buffer[3]) << 8) | (uint16_t)buffer[2];
i2c_read_n_byte(HTS221_SLV_ADDRESS, HTS221_TEMP_OUT_L_REG | BIT7, buffer ,2);
T_out = (((uint16_t)buffer[1]) << 8) | (uint16_t)buffer[0];
tmp_f = (float)(T_out - T0_out) * (float)(T1_degC - T0_degC) / (float)(T1_out - T0_out) + T0_degC;
return tmp_f;
}
void HTS221_Init(void)
{
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_WHO_AM_I_REG,buf,1);
buf[0] = BIT7 | BIT0;
i2c_write_n_byte(HTS221_SLV_ADDRESS,HTS221_CTRL_REG1, buf,1);
buf[0] = 0x3f; //0b00111111 tAvg=256 hAvg=512
i2c_write_n_byte(HTS221_SLV_ADDRESS,HTS221_AV_CONF_REG, buf,1);
}
void test() {
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_WHO_AM_I_REG,buf,1);
buf[0] = BIT7 | BIT0;
i2c_write_n_byte(HTS221_SLV_ADDRESS,HTS221_CTRL_REG1, buf,1);
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_STATUS_REG,buf,1);
if(buf[0] == 0x03)
{
t[0] = HTS221_Get_Temperature();
h[0] = HTS221_Get_Humidity();
}
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_CTRL_REG2,buf,1);
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_STATUS_REG,buf,1);
if(buf[0] == 0x03)
{
t[0] = HTS221_Get_Temperature();
h[0] = HTS221_Get_Humidity();
}
buf[0] = BIT0 ;
i2c_write_n_byte(HTS221_SLV_ADDRESS,HTS221_CTRL_REG2, buf,1);
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_CTRL_REG2,buf,1);
i2c_read_n_byte(HTS221_SLV_ADDRESS,HTS221_STATUS_REG,buf,1);
if(buf[0] == 0x03)
{
t[0] = HTS221_Get_Temperature();
h[0] = HTS221_Get_Humidity();
}
_NOP();
// i2c_write_n_byte(address,VL53L0X_REG_SYSRANGE_START, buf,1);
}
void HDC1080_Init(void)
{
uint8_t data[4];
data[0] = BIT7;//RESET
data[1] = 0x00;
i2c_write_n_byte((0x40 << 1),0x02,data,2);
}
float HDC1080_GetHumidity()
{
uint8_t data[4];
uint16_t temp;
float humidity;
hdc1080_i2c_read_n_byte((0x40 << 1),0x01,data,2);
temp = ((((uint16_t)data[0]) << 8) & 0xff00) + (((uint16_t)data[1]) & 0x00ff);
humidity = ((float)temp)*100/65536;
return humidity;
}
float HDC1080_GetTemperature()
{
uint8_t data[4];
uint16_t temp;
float temperature;
hdc1080_i2c_read_n_byte((0x40 << 1),0x00,data,2);
temp = ((((uint16_t)data[0]) << 8) & 0xff00) + (((uint16_t)data[1]) & 0x00ff);
temperature = (((float)(((uint32_t)temp) * 165))/65536) - 40;
return temperature;
}
int main( void )
{
char outBuf[64];//base64缓存
WDTCTL = WDTPW + WDTHOLD;//停止看门狗
PM5CTL0 &= ~LOCKLPM5;//这个是一定要加的，不然GPIO不能使用
dco_init();
i2c_init();//初始化I2C
SI7021_Init();
HTS221_Init();
HDC1080_Init();
uart_init();
//对比HTS221和HDC1080的湿度
while(0)
{
//test();
h[0] = HDC1080_GetHumidity();
delay(10000);
h[1] = HTS221_Get_Humidity();
sprintf(outBuf,"%f\t%f",h[0],h[1]);
uart_tx_string(outBuf);//输出到PC
uart_tx_string("\r\n");//换行
delay(100000);
}
//对比HTS221和HDC1080的温度
while(0)
{
//test();
t[0] = HDC1080_GetTemperature();
delay(10000);
t[1] = HTS221_Get_Temperature();
sprintf(outBuf,"%f\t%f",t[0],t[1]);
uart_tx_string(outBuf);//输出到PC
uart_tx_string("\r\n");//换行
delay(100000);
}
//对比HTS221和SHT21、SI7021的湿度
while(0)
{
h[0] = SI7021_GetHumidityRH();
delay(10000);
h[1] = HTS221_Get_Humidity();
sprintf(outBuf,"%f\t%f",h[0],h[1]);
uart_tx_string(outBuf);//输出到PC
uart_tx_string("\r\n");//换行
delay(100000);
}
//对比HTS221和SI7051、SHT21的温度
while(1)
{
//test();
t[0] = SI7021_GetTemperature();
delay(10000);
t[1] = HTS221_Get_Temperature();
sprintf(outBuf,"%f\t%f",t[0],t[1]);
uart_tx_string(outBuf);//输出到PC
uart_tx_string("\r\n");//换行
delay(100000);
}
}
void dco_init(void)
{
// Configure one FRAM waitstate as required by the device datasheet for MCLK
// operation beyond 8MHz _before_ configuring the clock system.
FRCTL0 = FRCTLPW | NWAITS_1;
// Clock System Setup
CSCTL0_H = CSKEY >> 8; // Unlock CS registers
CSCTL1 = DCORSEL | DCOFSEL_4; // Set DCO to 16MHz
CSCTL2 = SELA__VLOCLK | SELS__DCOCLK | SELM__DCOCLK; // Set SMCLK = MCLK = DCO,
// ACLK = VLOCLK
CSCTL3 = DIVA__1 | DIVS__1 | DIVM__1; // Set all dividers
CSCTL0_H = 0; // Lock CS registers
}