public synchronized void reqScannerParameters() {
        // not connected?
        if (!m_connected) {
            error(EClientErrors.NO_VALID_ID, EClientErrors.NOT_CONNECTED, "");
            return;
        }

        if (m_serverVersion < 24) {
          error(EClientErrors.NO_VALID_ID, EClientErrors.UPDATE_TWS,
                "  It does not support API scanner subscription.");
          return;
        }

        final int VERSION = 1;

        try {
            send(REQ_SCANNER_PARAMETERS);
            send(VERSION);
        }
        catch( Exception e) {
            error( EClientErrors.NO_VALID_ID,
                   EClientErrors.FAIL_SEND_REQSCANNERPARAMETERS, "" + e);
            close();
        }
    }