diff --git a/src/ATBAPP/ATBDeviceControllerPlugin.cpp b/src/ATBAPP/ATBDeviceControllerPlugin.cpp
index 892b4b8..e657ee5 100644
--- a/src/ATBAPP/ATBDeviceControllerPlugin.cpp
+++ b/src/ATBAPP/ATBDeviceControllerPlugin.cpp
@@ -311,6 +311,73 @@ void ATBDeviceControllerPlugin::cashCollect()
     }
 }
 
+
+void ATBDeviceControllerPlugin::cashCollect(const QString & amount)
+{
+    if (this->coinProcessor() != nsDeviceControllerInterface::COIN_PROCESSOR::CHANGER) {
+        this->cashCollect();
+        return;
+    }
+
+    // check if we must change coins:
+
+    // inserted amount
+    uint32_t amountInsertedInt = this->hw->getInsertedAmount();
+
+    bool ok;
+    uint32_t amountToPayInt = amount.toInt(&ok);
+
+    // check if we must change coins:
+    if (amountInsertedInt > amountToPayInt) {
+
+        uint32_t amountToChangeInt = amountInsertedInt - amountToPayInt;
+
+        qCritical() << "cashCollect(" << amount << ")";
+        qCritical() << "             amount to change: " << QString::number(amountToChangeInt);
+
+
+        // trigger changer:
+        emit this->cashPaymentChanging(nsDeviceControllerInterface::RESULT_STATE::SUCCESS,
+                                       QString::number(amountToChangeInt),
+                                       "",    // ErrorCode
+                                       "");   // ErrorDescription
+
+        // change
+        hw->changer_returnCoins(amountToChangeInt);
+
+        QTimer::singleShot(1000, this, &ATBDeviceControllerPlugin::onCashChangerState);
+
+    }
+    else {
+        // nothing to change:
+
+        qCritical() << "cashCollect(" << amount << ")";
+        qCritical() << "             nothing to change. ";
+
+
+        hw->vend_success();
+
+        QString amountString = QString::number(amountInsertedInt);
+
+        // inserted coins
+        uint32_t amountCoinsInt = CashUtils::getAmountOfInsertedCoins(this->hw);
+        QString amountCoinsString = QString::number(amountCoinsInt);
+
+        // inserted notes
+        uint32_t amountNotesInt = CashUtils::getAmountOfInsertedNotes(this->hw);
+        QString amountNotesString = QString::number(amountNotesInt);
+
+        emit this->cashPaymentFinished(nsDeviceControllerInterface::RESULT_STATE::SUCCESS,
+                                  amountString,
+                                  amountCoinsString,        // coins
+                                  amountNotesString,        // notes
+                                  0,                        // proposed change
+                                  "",
+                                  "");
+        this->currentCashState = CASH_STATE::CACHE_EMPTY;
+    }
+}
+
 void ATBDeviceControllerPlugin::cashAbort()
 {
     hw->vend_failed();
@@ -1444,6 +1511,10 @@ void ATBDeviceControllerPlugin::onCashChangerState()
                                   "");
         changerStateRequestCounter = 0;
         lastChangerResult = 0;
+
+        // finalize vending:
+        hw->vend_success();
+
         return;
     }
     else
@@ -1498,6 +1569,10 @@ void ATBDeviceControllerPlugin::onCashChangerState()
                                   errorDescription);
         changerStateRequestCounter = 0;
         lastChangerResult = 0;
+
+        // finalize vending:
+        hw->vend_success();
+
         return;
     }
 
diff --git a/src/ATBAPP/ATBDeviceControllerPlugin.h b/src/ATBAPP/ATBDeviceControllerPlugin.h
index 6a1ce44..53f562b 100644
--- a/src/ATBAPP/ATBDeviceControllerPlugin.h
+++ b/src/ATBAPP/ATBDeviceControllerPlugin.h
@@ -50,6 +50,7 @@ public:
     void requestStartCashInput(const QString & amount);
     void requestStopCashInput();
     void cashCollect();
+    void cashCollect(const QString & amount);
     void cashAbort();
 
     // read coin/cash processing variants -----------------------------------------
diff --git a/src/ATBAPP/DeviceControllerInterface.h b/src/ATBAPP/DeviceControllerInterface.h
index caae99f..8ad9581 100644
--- a/src/ATBAPP/DeviceControllerInterface.h
+++ b/src/ATBAPP/DeviceControllerInterface.h
@@ -60,9 +60,10 @@ public:
     virtual void requestStopCashInput() = 0;
 
     /**
-     * called e.g. on Button "NEXT" in pay-up (direct coin input)
+     * called e.g. after printing
      */
     virtual void cashCollect() = 0;
+    virtual void cashCollect(const QString & amount) = 0;
     virtual void cashAbort() = 0;
 
     // TASKS: Account -------------------------------------------------------------
@@ -138,6 +139,14 @@ signals:
                                      const QString & errorCode,
                                      const QString & errorDescription);
 
+    /**
+     * emitted if cashPayment has been finished, e.g. in result to task cashCollect():
+     * if coins in changer must be given back to user.
+     */
+    void cashPaymentChanging(nsDeviceControllerInterface::RESULT_STATE resultState,
+                                     const QString & changeValue,        // amount changed by changer/escrow
+                                     const QString & errorCode,
+                                     const QString & errorDescription);
     /**
      * emitted if cashPayment has been finished, e.g. in result to task cashCollect():
      *  -> ticket should be printed sucessfully
@@ -145,7 +154,7 @@ signals:
      * Provides data for logging, especially changed value
      */
     void cashPaymentFinished(nsDeviceControllerInterface::RESULT_STATE resultState,
-                                     const QString & newCashValue,  // total inserted amount amount
+                                     const QString & newCashValue,  // total inserted amount
                                      const QString & coinValue,     // inserted amount, paid with coins
                                      const QString & noteValue,     // inserted amount, paid with notes
                                      const QString & changeValue,   // amount changed by changer/escrow
@@ -203,7 +212,7 @@ signals:
 
 
 Q_DECLARE_INTERFACE(DeviceControllerInterface,
-                    "eu.atb.ptu.plugin.DeviceControllerInterface/1.1.6")
+                    "eu.atb.ptu.plugin.DeviceControllerInterface/1.2.0")
 
 
 namespace nsDeviceControllerInterface {