F_REF
m = config->sample_rate*512/1000*(n+2)*(1<<r)/(F_REF/1000)-2;
freq = (m+2)*(F_REF/1000)/(512*(n+2)*(1<<r)/1000);
port->config.sample_rate = ((float)m+2.0)*(F_REF/1000.0)/
