Hello,

After writing the code and kept it running overnight it is noticed that the readouts of the MEMS MiCS-4514 are never changing for the various gasses, but the OX and RED data is changing.

Performing a basic test, i used a small amount of Whiskey to evaporate near the sensor, which changed the OX and RED values. Though the C2H5OH shows always 0 ppm. NO2 always shows 10ppm which is the max.

As a precaution i bought 2 of these sensors and they give exactly the same results. So it must be a coding issue…???

Code:

//
//
//
#include "defines.h"
#include "enums.h"
#include "LoopMetrics.h"
#include "LogWriter.h"
#include "I2C_Driver.h"

#pragma region PUBLIC FUNCTIONS
void I2C_DriverClass::Init()
{
uint32_t speed = 100000;
Wire.begin((int)I2C_SDA, (int)I2C_SCL, speed);

mics = new DFRobot_MICS_I2C(&Wire, 0x75);

while (!mics->begin()) {
Serial.println("NO Deivces !");
delay(1000);
} Serial.println("Device connected successfully !");

uint8_t mode = mics->getPowerState();

if (mode == SLEEP_MODE)
{
mics->wakeUpMode();
Serial.println("wake up sensor success!");
}
else
{
Serial.println("The sensor is wake up mode");
}

}

void I2C_DriverClass::ExecuteTask()
{
float gasdata = mics->getGasData(CH4);
String results = "CH4,";
results += String(gasdata) + ",";

gasdata = mics->getGasData(C2H5OH);
results += "C2H5OH,";
results += String(gasdata) + ",";

gasdata = mics->getGasData(H2);
results += "H2,";
results += String(gasdata)+ ",";

gasdata = mics->getGasData(NH3);
results += "NH3,";
results += String(gasdata);

gasdata = mics->getGasData(CO);
results += "CO,";
results += String(gasdata) + ",";

gasdata = mics->getGasData(NO2);
results += "NO2,";
results += String(gasdata) + ",";

int16_t ox_data = 0;
int16_t red_data = 0;

ox_data = mics->getADCData(OX_MODE);
red_data = mics->getADCData(RED_MODE);
results += "ox data,";
results += String(ox_data) + ",";
results += "red data,";
results += String(red_data);

LogWriter.ConsoleOutputLn(results);

}

results:

11:57:32.499 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,448
11:57:37.499 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,448
11:57:42.499 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:57:47.499 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:57:52.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:57:57.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:58:02.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,450
11:58:07.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:58:12.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,449
11:58:17.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,450
11:58:22.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,451 ←- started adding some alcohol vapour
11:58:27.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,805,red data,445
11:58:32.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,804,red data,328
11:58:37.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,803,red data,372
11:58:42.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,804,red data,281
11:58:47.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,202
11:58:52.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,432
11:58:57.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,803,red data,447
11:59:02.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,158
11:59:07.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,397
11:59:12.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,398
11:59:17.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,434
11:59:22.498 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,174
11:59:27.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,258
11:59:32.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,408
11:59:37.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,226
11:59:42.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,263
11:59:47.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,284
11:59:52.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,262
11:59:57.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,350
12:00:02.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,462
12:00:07.497 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,269
12:00:12.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,322
12:00:17.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,271
12:00:22.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,297
12:00:27.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,318
12:00:32.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,389
12:00:37.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,467
12:00:42.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,178
12:00:47.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,318
12:00:52.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,792,red data,173
12:00:57.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,361
12:01:02.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,500
12:01:07.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,477
12:01:12.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,276
12:01:17.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,445
12:01:22.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,353
12:01:27.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,437
12:01:32.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,451
12:01:37.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,438
12:01:42.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,385
12:01:47.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,482
12:01:52.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,448
12:01:57.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,251
12:02:02.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,339
12:02:07.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,439
12:02:12.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,388
12:02:17.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,296
12:02:22.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,325
12:02:27.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,372
12:02:32.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,396
12:02:37.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,385
12:02:42.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,427
12:02:47.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,795,red data,166
12:02:52.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,445
12:02:57.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,178
12:03:02.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,257
12:03:07.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,796,red data,195
12:03:12.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,384
12:03:17.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,295
12:03:22.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,419
12:03:27.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,191
12:03:32.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,334
12:03:37.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,334
12:03:42.496 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,366
12:03:47.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,324
12:03:52.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,357
12:03:57.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,399
12:04:02.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,356
12:04:07.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,351
12:04:12.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,441
12:04:17.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,438
12:04:22.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,390
12:04:27.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,280
12:04:32.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,398
12:04:37.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,798,red data,250
12:04:42.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,301
12:04:47.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,386
12:04:52.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,193
12:04:57.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,382
12:05:02.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,333
12:05:07.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,797,red data,196
12:05:12.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,433
12:05:17.495 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,505 ←- closed the bottle containing a small quantity of Whiskey :-)
12:05:22.494 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,799,red data,519
12:05:27.494 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,519
12:05:32.494 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,521
12:05:37.494 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,800,red data,521
12:05:42.493 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,519
12:05:47.493 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,520
12:05:52.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,801,red data,521
12:05:57.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,520
12:06:02.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,519
12:06:07.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,519
12:06:12.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,518
12:06:17.492 - (Debug) - CH4,0.00,C2H5OH,0.00,H2,0.00,NH3,0.00CO,0.00,NO2,10.00,ox data,802,red data,516 ←- results return to normal though 0 ppm on all except NO2 which is always 10ppm