- Sat Jan 30, 2016 10:16 am
#39993
Guys,
i'm just starting with it, please be patient.
I plan to make a small indoor Air Quality meter with the WAVESHARE sharp module: (https://botland.com.pl/index.php?controller=attachment&id_attachment=1286).
I plug it into 3.3 ,GND, A0 and D6.
Everything seems to work fine, but the ADC raw values do not exceed: RAW Analog: 114
I read that ESP has 1.0V on ADC, the sensor has 5.0V - how can i make it work ? Is it possible to be done with software only, without any additional hardware?
Serial Output:
The sheets say max ug/m3 is 500, however i get 1133 and i believe it can be caused by the ADC as the code works perfectly on Arduino UNO..
Code below, taken from WaveShare and modified to fit ESP pins.
i'm just starting with it, please be patient.
I plan to make a small indoor Air Quality meter with the WAVESHARE sharp module: (https://botland.com.pl/index.php?controller=attachment&id_attachment=1286).
I plug it into 3.3 ,GND, A0 and D6.
Everything seems to work fine, but the ADC raw values do not exceed: RAW Analog: 114
I read that ESP has 1.0V on ADC, the sensor has 5.0V - how can i make it work ? Is it possible to be done with software only, without any additional hardware?
Serial Output:
Code: Select all
RAW Analog: 45 miliVOLT: 2016.99 DUST ug/m3: 403.40
RAW Analog: 44 miliVOLT: 1963.28 DUST ug/m3: 392.66
RAW Analog: 41 miliVOLT: 1802.15 DUST ug/m3: 360.43
RAW Analog: 40 miliVOLT: 1748.44 DUST ug/m3: 349.69
RAW Analog: 43 miliVOLT: 1909.57 DUST ug/m3: 381.91
RAW Analog: 38 miliVOLT: 1641.02 DUST ug/m3: 328.20
RAW Analog: 35 miliVOLT: 1479.88 DUST ug/m3: 295.98
RAW Analog: 36 miliVOLT: 1533.59 DUST ug/m3: 306.72
RAW Analog: 36 miliVOLT: 1533.59 DUST ug/m3: 306.72
...
RAW Analog: 115 miliVOLT: 5776.76 DUST ug/m3: 1155.35
RAW Analog: 114 miliVOLT: 5723.05 DUST ug/m3: 1144.61
RAW Analog: 114 miliVOLT: 5723.05 DUST ug/m3: 1144.61
RAW Analog: 115 miliVOLT: 5776.76 DUST ug/m3: 1155.35
RAW Analog: 89 miliVOLT: 4380.27 DUST ug/m3: 876.05
RAW Analog: 113 miliVOLT: 5669.34 DUST ug/m3: 1133.87
RAW Analog: 90 miliVOLT: 4433.98 DUST ug/m3: 886.80
RAW Analog: 72 miliVOLT: 3467.19 DUST ug/m3: 693.44
The sheets say max ug/m3 is 500, however i get 1133 and i believe it can be caused by the ADC as the code works perfectly on Arduino UNO..
Code below, taken from WaveShare and modified to fit ESP pins.
Code: Select all
/*********************************************************************************************************
*
* File : DustSensor
* Hardware Environment:
* Build Environment : Arduino
* Version : V1.0.5-r2
* By : WaveShare
*
* (c) Copyright 2005-2011, WaveShare
* http://www.waveshare.net
* http://www.waveshare.com
* All Rights Reserved
*
*********************************************************************************************************/
#define COV_RATIO 0.2 //ug/mmm / mv
#define NO_DUST_VOLTAGE 400 //mv
#define SYS_VOLTAGE 5000
/*
I/O define
*/
const int iled = 13; //drive the led of sensor
const int vout = A0; //analog input
/*
variable
*/
float density, voltage;
int adcvalue;
/*
private function
*/
int Filter(int m)
{
static int flag_first = 0, _buff[10], sum;
const int _buff_max = 10;
int i;
if(flag_first == 0)
{
flag_first = 1;
for(i = 0, sum = 0; i < _buff_max; i++)
{
_buff[i] = m;
sum += _buff[i];
}
return m;
}
else
{
sum -= _buff[0];
for(i = 0; i < (_buff_max - 1); i++)
{
_buff[i] = _buff[i + 1];
}
_buff[9] = m;
sum += _buff[9];
i = sum / 10.0;
return i;
}
}
void setup(void)
{
pinMode(iled, OUTPUT);
digitalWrite(iled, LOW); //iled default closed
Serial.begin(9600); //send and receive at 9600 baud
Serial.print("*********************************** WaveShare ***********************************\n");
}
void loop(void)
{
/*
get adcvalue
*/
digitalWrite(iled, HIGH);
delayMicroseconds(280);
adcvalue = analogRead(vout);
digitalWrite(iled, LOW);
// adcvalue = Filter(adcvalue);
/*
covert voltage (mv)
*/
voltage = (SYS_VOLTAGE / 1024.0) * adcvalue * 11;
/*
voltage to density
*/
if(voltage >= NO_DUST_VOLTAGE)
{
voltage -= NO_DUST_VOLTAGE;
density = voltage * COV_RATIO;
}
else
density = 0;
/*
display the result
*/
Serial.print("RAW Analog: "+String(adcvalue)+" miliVOLT: "+String(voltage)+" DUST ug/m3: "+String(density)+"\n");
delay(1000);
}
