diff --git a/include/interfaces.h b/include/interfaces.h
index 7234315..51ec7e1 100755
--- a/include/interfaces.h
+++ b/include/interfaces.h
@@ -24,7 +24,8 @@ struct T_emp
 
    // dynamic:
    uint8_t state;      // step counter of EMP (electronic coin checker) FSM (finite state machine):
-       // 0=start command
+   /*
+   // 0=start command
        // 1=powered, do emp ini, send reset
        // 2=delay
        // 3=wait for response, requesting status after response
@@ -39,7 +40,7 @@ struct T_emp
        // 90: stop all, 1s delay
        // 99: off, all stopped
 
-
+*/
    uint8_t pollingRunning;
    uint8_t paymentRunning;
 
@@ -238,6 +239,7 @@ struct T_dynamicCondition
         uint8_t lastVDoorState;
         uint8_t lastCBstate;
         char        paymentInProgress;
+        // Version Szeged:  aug2023
         //	0: stopped by timeout
         //  1: running  2: wait4lastCoin
         //				3: payment stopped manually, coins in Escrow
@@ -246,6 +248,21 @@ struct T_dynamicCondition
         //			    6: coins encashed   7:coins returned
         //				8: CoinChecker or MDB on Error
 
+        // since Schoenau with bill and changer, nov2023
+        //0 = no payment
+        //will be set to 1 by cash_startCollection()
+        //neu 1: wait for devices getting ready for payment
+        //2 = payment,
+        //3 = wait for last coin/bill
+        //4 = Bezahlvorgang manuell beendet
+        //5 = payment stopped autom, amount collected, coins in Escrow
+        //6 = Bezahlvorgang beendet weil ZK voll
+        //4,5,6: payment done, keep on polling, wait for cash or return command
+        //7 = encash collected money from coin escrow into cash box
+        //8 = return "amountToReturn", can be complete inserted amount or only overpayment
+        //9 = wait for changer result
+        //10= print refund receipt with "amountToReturn"
+
 
         char        res1;
         uint16_t    U_Batt;
@@ -2252,14 +2269,23 @@ public:
     virtual void bna_requestCurrentNotes() const {}
     // send command to DC in order to get transaction data
 
-    virtual uint8_t bna_getCurrentNotes(uint16_t latestBill, uint16_t *currentNotes) const {
+    virtual uint8_t bna_getCurrentNotes(uint16_t latestBill, uint16_t *currentNotes) const
+    {
         Q_UNUSED(latestBill);
         Q_UNUSED(currentNotes);
         return 0;
     }
     // returns number of collected bank notes since start-command (current transaction)
-    //  latestBill: last accepted bank note, value in cent
-    //  currentNotes an array with up to 16 (further) notes collected
+    // return value: numbers of bills or 99 in case of error
+    //  latestBill: not used
+    // in case of error: currentNotes[0,1,2,3] = 1..4 error number(s)
+    // in normal case:
+    //  currentNotes[0]: last bill in cent (e.g. 1000 = 10€)
+    //  currentNotes[1]: bin 1 = bill is still in escrow   else bill is stacked
+    //       note: by now (dec2023) escrow is not used, bills always go to stacker (box)
+    //  currentNotes[2]: total sum of bills in cent, low word (16bit)
+    //  currentNotes[3]: total sum of bills in cent, high word (16bit)
+
 
     virtual void bna_requestStackerLevel() const {}