saves the PID values from RAM to EEPROM

def save_pid_eeprom(self):
        """ saves the PID values from RAM to EEPROM

        """
        pval = self.get_position_p()
        ival = self.get_position_i()
        dval = self.get_position_d()

        #write P value
        pvalue_msb = int(pval) >> 8
        pvalue_lsb = int(pval) & 0xff

        data_p = []
        data_p.append(0x0B)
        data_p.append(self.servoid)
        data_p.append(EEP_WRITE_REQ)
        data_p.append(POSITION_KP_EEP)
        data_p.append(BYTE2)
        data_p.append( pvalue_lsb)
        data_p.append( pvalue_msb)
        send_data(data_p)

        # write I value
        ivalue_msb = int(ival) >> 8
        ivalue_lsb = int(ival) & 0xff

        data_i = []
        data_i.append(0x0B)
        data_i.append(self.servoid)
        data_i.append(EEP_WRITE_REQ)
        data_i.append(POSITION_KI_EEP)
        data_i.append(BYTE2)
        data_i.append( ivalue_lsb)
        data_i.append( ivalue_msb)
        send_data(data_i)

        # write D value
        dvalue_msb = int(dval) >> 8
        dvalue_lsb = int(dval) & 0xff

        data_d = []
        data_d.append(0x0B)
        data_d.append(self.servoid)
        data_d.append(EEP_WRITE_REQ)
        data_d.append(POSITION_KD_EEP)
        data_d.append(BYTE2)
        data_d.append( dvalue_lsb)
        data_d.append( dvalue_msb)
        send_data(data_d)