spi speed with ioctl ofxGPIO

ofxgpio-spi-speed.cpp

#include "ofxGPIO.h"

/*
        ofxGPIO
        speed test SPI 
*/


int main(int argc, char ** argv)
{
        if(argc < 2)
        {
                cout << "Param: device-spi" << endl;
                exit(0);
        }

        MCP a2d;
        int i,a2dVal = 0;
        unsigned char data[3];
        struct timespec start, end;
        double fq,sec,nsec,msec;

        a2d.setup(argv[1], SPI_MODE_0, 1000000, 8);

        while(i<500) {
                unsigned static int a2dChannel = 0;

                data[0] = 1;
                data[1] = 0b10000000 |( ((a2dChannel & 7) << 4));
                data[2] = 0;

                clock_gettime(CLOCK_REALTIME, &start);
                a2d.readWrite(data);
                a2dVal = 0;
                a2dVal = (data[1]<< 8) & 0b1100000000;
                a2dVal |=  (data[2] & 0xff);
                cout << "Result channel["<< a2dChannel <<"]: " << a2dVal << "; ";
                clock_gettime(CLOCK_REALTIME, &end);

                sec  = ((double)end.tv_sec) - ((double)start.tv_sec);
                nsec = ((double)end.tv_nsec) - ((double)start.tv_nsec);
                msec = round(nsec / 1000);
                fq   = (1.0e9 / nsec);

                cout << "Time s[ " << sec << " ] ms[ " <<  msec << " ] ns[ " << nsec << " ]; Freq Hz[ " <<  fq << " ]" << endl;

                a2dChannel++;
                if(a2dChannel >= 8) a2dChannel = 0;
                i++;
        }
        a2d.xclose();

        return 0;
}