C++ API for MQ9 gas sensor. More...

Detailed Description

The Grove MQ9 Gas Sensor module is useful for gas leakage detecting (in home and industry). It can detect Carbon Monoxide, Coal Gas and Liquefied Gas. It's sensitivty is 10-1000ppmCO 100-10000PPm Gas.

int
main(int argc, char **argv)
{
    sensor = new upm::MQ9(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
	MQ9 (int gasPin)

	~MQ9 ()

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)