C++ API for MQ2 gas sensor. More...

Detailed Description

The Grove - Gas Sensor (MQ2) module is useful for gas leakage detecting (in home and industry). It can detect LPG, i-butane, methane, alcohol, Hydrogen, smoke and other combustible gases. It's a medium sensitivity sensor with a detect concentration of 300-10000ppm.

int
main(int argc, char **argv)
{
    sensor = new upm::MQ2(0);
    signal(SIGINT, sig_handler);
    thresholdContext ctx;
    ctx.averageReading = 0;
    ctx.runningAverage = 0;
    ctx.averagedOver   = 2;
    while (!is_running) {
        int len = sensor->getSampledWindow (2, 128, buffer);
        if (len) {
            int thresh = sensor->findThreshold (&ctx, 30, buffer, len);
            sensor->printGraph(&ctx, 5);
            if (thresh) {
                // do something ....
            }
        }
    }
    std::cout << "exiting application" << std::endl;
    delete sensor;
    return 0;
}

Public Member Functions
	MQ2 (int gasPin)

	~MQ2 ()

std::string	name ()

Public Member Functions inherited from Gas
	Gas (int gasPin)

	~Gas ()

virtual int	getSampledWindow (unsigned int freqMS, unsigned int numberOfSamples, uint16_t *buffer)

virtual int	findThreshold (thresholdContext ctx, unsigned int threshold, uint16_t buffer, unsigned int len)

virtual int	getSampledData (thresholdContext *ctx)

virtual int	getSample (thresholdContext *ctx)

virtual void	printGraph (thresholdContext *ctx, uint8_t resolution)