diff --git a/Firmware/src/AppleIISd.inc b/Firmware/src/AppleIISd.inc
index e1838b9..8ff13b3 100644
--- a/Firmware/src/AppleIISd.inc
+++ b/Firmware/src/AppleIISd.inc
@@ -1,10 +1,10 @@
 ;*******************************
 ;
 ; Apple][Sd Firmware
-; Version 1.2
+; Version 1.2.2
 ; Defines
 ;
-; (c) Florian Reitz, 2017 - 2018
+; (c) Florian Reitz, 2017 - 2020
 ;
 ; X register usually contains SLOT16
 ; Y register is used for counting or SLOT
@@ -44,7 +44,6 @@ DRVNUM      :=    $0678
 CURSLOT     :=    $07F8       ; $Cs
 
 ; Rom equates
-KNOWNRTS    :=    $FF58
 OAPPLE      :=    $C061       ; open apple key
 DATA        :=    $C080
 CTRL        :=    DATA+1
diff --git a/Firmware/src/AppleIISd.s b/Firmware/src/AppleIISd.s
index 46f08bb..d3c439c 100644
--- a/Firmware/src/AppleIISd.s
+++ b/Firmware/src/AppleIISd.s
@@ -57,9 +57,8 @@
             LDX   #$3C        ; is a disk controller
 
             SEI               ; find slot
-            LDA   #$60        ; opcode for RTS
-            STA   SLOT
-            JSR   SLOT
+            BIT   $CFFF
+            JSR   KNOWNRTS
             TSX
             LDA   $0100,X
             CLI
@@ -72,7 +71,6 @@
             ASL   A
             STA   SLOT16      ; $s0
             TAX               ; X holds now SLOT16
-            BIT   $CFFF
 
             LDY   #0          ; display copyright message
 @DRAW:      LDA   TEXT,Y
@@ -144,9 +142,8 @@ DRIVER:     CLC               ; ProDOS entry
 
 ; Has this to be done every time this gets called or only on boot???
             SEI
-            LDA   #$60        ; opcode for RTS
-            STA   SLOT
-            JSR   SLOT
+            BIT   $CFFF
+            JSR   KNOWNRTS
             TSX
             LDA   $0100,X
             CLI
@@ -160,7 +157,6 @@ DRIVER:     CLC               ; ProDOS entry
             ASL   A
             STA   SLOT16      ; $s0
             TAX               ; X holds now SLOT16
-            BIT   $CFFF
 
             JSR   CARDDET
             BCC   @INITED
@@ -358,7 +354,7 @@ INIT:       STZ   CTRL,X      ; reset SPI controller
             ORA   #SS0
             STA   SS,X
             TYA               ; retval in A
-            RTS
+KNOWNRTS:   RTS
 
 
 TEXT:       .asciiz " Apple][Sd v1.2.2 (c)2020 Florian Reitz"