Test ADC on Audio CODEC

vpp = [
    0.4270
    0.8430
    1.6250
    2.0630
    3.0940
    ];
counts = [
        3600
        7290
       14054
       18207
       27049
       ];
b = polyfit(vpp,counts,1);
fprintf('slope %g y-intercept %g\n',b);
v = [0.1 3.5];
plot(vpp,counts,'o',v,polyval(b,v))
xlabel('V peak-to-peak (V)');
ylabel('counts');

slope 8809.3 y-intercept -146.496