User Manual

12/07/2016
GroveGasSensor(O₂)Wiki
3/5
byusingaUSBcable.
3.CopyandpastethecodebelowtoanewArduinosketch.Pleaseread
this(http://www.seeedstudio.com/wiki/Upload_Code)ifyoudonotknow
howtoupload.
//testGrove‐GasSensor(O2)
floatVoutArray[]={0.30769,20.00000,40.00000,60.00000,120.61538,186.76923};
floatO2ConArray[]={0.00018,2.66129,5.32258,8.05300,16.19851,25.15367};

voidsetup(){
//putyoursetupcodehere,torunonce:
Serial.begin(9600);

}

voidloop(){
//putyourmaincodehere,torunrepeatedly:

Serial.print("Vout=");
Serial.print(readO2Vout(A0));
Serial.print("V,ConcentrationofO2is");
Serial.println(readConcentration(A0));

delay(500);

}

floatreadO2Vout(uint8_tanalogpin)
{

//Voutsamplesarewithreferenceto3.3V
floatMeasuredVout=analogRead(A0)*(3.3/1023.0);
returnMeasuredVout;

}

floatreadConcentration(uint8_tanalogpin)
{


//Voutsamplesarewithreferenceto3.3V
floatMeasuredVout=analogRead(A0)*(3.3/1023.0);
floatConcentration=FmultiMap(MeasuredVout,VoutArray,O2ConArray,6);
floatConcentration_Percentage=Concentration*100;

/**************************************************************************

TheO2ConcentrationinpercentageiscalculatedbasedonwikipageGraph


ThedatafromthegraphisextractedusingWebPlotDigitizer
http://arohatgi.info/WebPlotDigitizer/app/

VoutArray[]andO2ConArray[]aretheseextracteddata.UsingMultiMap,thedata
isinterpolatedtogettheO2Concentrationinpercentage.

Thisimplementationusesfloatingpointarithmeticandhencewillconsume
moreflash,RAMandtime.

TheO2Concentrationinpercentageisanapproximationanddependsontheaccuracyof
Graphused.

***************************************************************************/

returnConcentration_Percentage;
}


//ThiscodeusesMultiMapimplementationfromhttp://playground.arduino.cc/Main/MultiMap

floatFmultiMap(floatval,float*_in,float*_out,uint8_tsize)
{
//takecarethevalueiswithinrange
//val=constrain(val,_in[0],_in[size‐1]);
if(val<=_in[0])return_out[0];
if(val>=_in[size‐1])return_out[size‐1];

//searchrightinterval
uint8_tpos=1;//_in[0]allreadytested
while(val>_in[pos])pos++;

//thiswillhandleallexact"points"inthe_inarray
if(val==_in[pos])return_out[pos];

tfortherest