diff --git a/main.cpp b/main.cpp
index 4783aea..a925bc3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -25,6 +25,9 @@ static void updateBinary(std::unique_ptr<hwinf> hw,     // update d2dc*.bin
                          char const *baudrate,
                          char const *serialInterface) {
     for (int i=0; i < 1;++i) {
+        qDebug() << "file to send to DC ..." << fileToSendToDC;
+        qDebug() << "baudrate ............." << baudrate;
+        qDebug() << "serial interface ....." << serialInterface;
         hw->dc_updateDC(fileToSendToDC, baudrate, serialInterface);
         std::this_thread::sleep_for(std::chrono::milliseconds(3000));
     }
@@ -35,13 +38,14 @@ static void updatePrinterConf(std::unique_ptr<hwinf> hw, // update printer-file
                               QVector<int> nrOfTemplate,
                               QVector<QString> fileToSendToDC,
                               QString br, QString serial) {
-    for (int i=0; i < 1;++i) {
-        //hw->dc_updatePrinterTemplate(hwapi::FileTypeJson::PRINTER,
-        //                             nrOfTemplate, fileToSendToDC,
-        //                             br, serial);
+    // for (int i = 0; i < 1; ++i) {
+    if (nrOfTemplate.size() == 1 && fileToSendToDC.size() == 1) {
+        hw->dc_updatePrinterTemplate(hwapi::FileTypeJson::PRINTER,
+                                     nrOfTemplate, fileToSendToDC,
+                                     br, serial);
 
-        hw->dc_printTemplate(hwapi::FileTypeJson::PRINTER,
-                             nrOfTemplate, br, serial);
+        // hw->dc_printTemplate(hwapi::FileTypeJson::PRINTER,
+        //                     nrOfTemplate, br, serial);
     }
     QCoreApplication::quit();
 }
@@ -56,7 +60,7 @@ int main(int argc, char *argv[]) {
         //setDebugLevel(QtMsgType::QtDebugMsg);
     }
 
-    if (argc > 2) {
+    if (argc != 2) {
         qCritical() << "Usage: " << argv[0] << "<file to send to dc>";
         return -1;
     }
@@ -72,17 +76,29 @@ int main(int argc, char *argv[]) {
         ret = a.exec();
         t.join();
     } else {
-        QVector<QString> fnames{"DC2C_print01.json",
-                                "DC2C_print02.json",
-                                "DC2C_print03.json"};
-        QVector<int> templateIdx{1,2,3};
-        //if (fname.startsWith("DC2C_print") && fname.endsWith(".json")) {
-        //int const nrOfTemplate = fname.midRef(10, 2).toInt();
-        std::thread t(updatePrinterConf, std::move(hw), templateIdx, fnames,
-                     "115200", SERIAL_PORT);
-        ret = a.exec();
-        t.join();
-        //}
+        if (fname.startsWith("DC2C_print") && fname.endsWith(".json")) {
+            qDebug() << "downloading" << fname << "to dc...";
+
+            QVector<QString> fnames;
+            QVector<int> templateIdx;
+
+            int const nrOfTemplate = fname.midRef(10, 2).toInt();
+            if (nrOfTemplate <= 0 && nrOfTemplate > 32) {
+                qCritical() << "wrong template number" << nrOfTemplate;
+                return -1;
+            }
+
+            fnames.append(fname);
+            templateIdx.append(nrOfTemplate);
+
+            std::thread t(updatePrinterConf, std::move(hw),
+                          templateIdx,
+                          fnames,
+                          "115200", SERIAL_PORT);
+
+            ret = a.exec();
+            t.join();
+        }
     }
 
     return ret;