diff --git a/src/constants.a b/src/constants.a
index 6301ae6..aaeacf4 100644
--- a/src/constants.a
+++ b/src/constants.a
@@ -17,7 +17,7 @@
 ;~7400...... - program data (approximate)
 ;
 
-kPitchDarkBinaryAddress   = $3F4D
+kPitchDarkBinaryAddress   = $3F41
 
 kGameInfoBuffer           = $0800    ; used by LoadGameInfo
 kProDOSFileBuffer         = $1C00    ; 1K buffer for ProDOS MLI calls
diff --git a/src/pitchdark.a b/src/pitchdark.a
index 88377b3..d2e2d06 100644
--- a/src/pitchdark.a
+++ b/src/pitchdark.a
@@ -14,8 +14,8 @@
 
 *=kPitchDarkBinaryAddress
 
-         jsr   QuitUnless128KAnd65C02; check minimum hardware requirements
          !source "src/pitchdark.init.a"
+
          jsr   LoadGameInfo          ; get current game description and game-specific options
          jsr   WGInit                ; initialize WeeGUI
          ldx   #WGEnableMouse        ; enable mouse support
diff --git a/src/pitchdark.init.a b/src/pitchdark.init.a
index df55bfa..d85f47f 100644
--- a/src/pitchdark.init.a
+++ b/src/pitchdark.init.a
@@ -1,3 +1,14 @@
+;------------------------------------------------------------------------------
+; check machine requirements (128K with 65C02) and quit to ProDOS if not met
+;------------------------------------------------------------------------------
+         lda   MACHID
+         and   #$30
+         cmp   #$30                  ; 128K?
+         beq   +                     ; yes, continue
+-        jmp   QuitToProDOS
++        inc                         ; 65C02-only INC instruction will clear Z flag
+         beq   -                     ; if Z flag is still set, this is not a 65C02
+
 ;------------------------------------------------------------------------------
 ; disconnect ProDOS /RAM disk in S3,D2
 ; (does not affect other RAM disks like RAMWorks or RAMFactor)
diff --git a/src/prodos.mli.a b/src/prodos.mli.a
index 2d8d68f..d153d04 100644
--- a/src/prodos.mli.a
+++ b/src/prodos.mli.a
@@ -9,7 +9,6 @@
 ; - SaveFile
 ; - SetPrefix
 ; - GetFileInfo
-; - QuitToProDOS
 ;
 
 ; MLI command codes
@@ -390,14 +389,6 @@ _setprefix
          ldy   #PC_SETPREFIX
          jmp   mli
 
-QuitUnless128KAnd65C02
-         lda   MACHID
-         and   #$30
-         cmp   #$30                  ; 128K?
-         bne   QuitToProDOS
-+        inc                         ; 65C02-only INC instruction will clear Z flag
-         bne   mliexit               ; if Z flag is clear, this is a 65C02 (good)
-                                     ; if Z flag is set, this is not a 65C02 (bad) and execution falls through here
 QuitToProDOS
          lda   #CMD_QUIT
          ldy   #PC_QUIT