diff --git a/A2Mac.xcodeproj/project.pbxproj b/A2Mac.xcodeproj/project.pbxproj
index cfc451a..0143881 100644
--- a/A2Mac.xcodeproj/project.pbxproj
+++ b/A2Mac.xcodeproj/project.pbxproj
@@ -49,8 +49,8 @@
 		325EB6A02401118300C6B4A4 /* Crossfire.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6952401118200C6B4A4 /* Crossfire.woz */; };
 		325EB6A12401118300C6B4A4 /* Wavy Navy.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6962401118200C6B4A4 /* Wavy Navy.woz */; };
 		325EB6A22401118300C6B4A4 /* Wavy Navy.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6962401118200C6B4A4 /* Wavy Navy.woz */; };
-		325EB6A32401118300C6B4A4 /* qbit.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6972401118200C6B4A4 /* qbit.woz */; };
-		325EB6A42401118300C6B4A4 /* qbit.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6972401118200C6B4A4 /* qbit.woz */; };
+		325EB6A32401118300C6B4A4 /* Qbit.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6972401118200C6B4A4 /* Qbit.woz */; };
+		325EB6A42401118300C6B4A4 /* Qbit.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6972401118200C6B4A4 /* Qbit.woz */; };
 		325EB6A52401118300C6B4A4 /* ProDOS_312.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6982401118200C6B4A4 /* ProDOS_312.woz */; };
 		325EB6A62401118300C6B4A4 /* ProDOS_312.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6982401118200C6B4A4 /* ProDOS_312.woz */; };
 		325EB6A72401118300C6B4A4 /* ProDOS_402_System.woz in Resources */ = {isa = PBXBuildFile; fileRef = 325EB6992401118200C6B4A4 /* ProDOS_402_System.woz */; };
@@ -68,14 +68,12 @@
 		32BFFB6E22EACC660003B53F /* A2MacTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB6D22EACC660003B53F /* A2MacTests.swift */; };
 		32BFFB7922EACC660003B53F /* A2MacUITests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB7822EACC660003B53F /* A2MacUITests.swift */; };
 		32C45306232E3EEF0000EBA1 /* RepeatingTimer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32C45305232E3EEF0000EBA1 /* RepeatingTimer.swift */; };
-		32C4530B2331F7220000EBA1 /* 6502.c in Sources */ = {isa = PBXBuildFile; fileRef = 32439F7422ECD8AD0077AAE0 /* 6502.c */; };
 		32C4530C2331F7220000EBA1 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB5C22EACC630003B53F /* ViewController.swift */; };
 		32C4530D2331F7220000EBA1 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB5A22EACC630003B53F /* AppDelegate.swift */; };
 		32C453112331F7220000EBA1 /* fail1.txt in Resources */ = {isa = PBXBuildFile; fileRef = 32EDB7A123272CA80073AF2D /* fail1.txt */; };
 		32C453122331F7220000EBA1 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 32BFFB5E22EACC660003B53F /* Assets.xcassets */; };
 		32C453132331F7220000EBA1 /* apple.rom in Resources */ = {isa = PBXBuildFile; fileRef = 32439F8422ECD8AD0077AAE0 /* apple.rom */; };
 		32C453152331F7220000EBA1 /* 6502_functional_test.bin in Resources */ = {isa = PBXBuildFile; fileRef = 326ED2EE232D7A0000A41337 /* 6502_functional_test.bin */; };
-		32C4531D2331FED90000EBA1 /* 6502.c in Sources */ = {isa = PBXBuildFile; fileRef = 32439F7422ECD8AD0077AAE0 /* 6502.c */; };
 		32C4531E2331FED90000EBA1 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB5C22EACC630003B53F /* ViewController.swift */; };
 		32C4531F2331FED90000EBA1 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 32BFFB5A22EACC630003B53F /* AppDelegate.swift */; };
 		32C453232331FED90000EBA1 /* fail1.txt in Resources */ = {isa = PBXBuildFile; fileRef = 32EDB7A123272CA80073AF2D /* fail1.txt */; };
@@ -172,7 +170,7 @@
 		325EB6942401118200C6B4A4 /* Lode Runner.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = "Lode Runner.woz"; sourceTree = "<group>"; };
 		325EB6952401118200C6B4A4 /* Crossfire.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = Crossfire.woz; sourceTree = "<group>"; };
 		325EB6962401118200C6B4A4 /* Wavy Navy.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = "Wavy Navy.woz"; sourceTree = "<group>"; };
-		325EB6972401118200C6B4A4 /* qbit.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = qbit.woz; sourceTree = "<group>"; };
+		325EB6972401118200C6B4A4 /* Qbit.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = Qbit.woz; sourceTree = "<group>"; };
 		325EB6982401118200C6B4A4 /* ProDOS_312.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = ProDOS_312.woz; sourceTree = "<group>"; };
 		325EB6992401118200C6B4A4 /* ProDOS_402_System.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = ProDOS_402_System.woz; sourceTree = "<group>"; };
 		325EB69A2401118300C6B4A4 /* Sneakers.woz */ = {isa = PBXFileReference; lastKnownFileType = file; path = Sneakers.woz; sourceTree = "<group>"; };
@@ -400,7 +398,7 @@
 				325EB6982401118200C6B4A4 /* ProDOS_312.woz */,
 				325EB68F23FE028800C6B4A4 /* Donkey Kong.woz */,
 				325EB6992401118200C6B4A4 /* ProDOS_402_System.woz */,
-				325EB6972401118200C6B4A4 /* qbit.woz */,
+				325EB6972401118200C6B4A4 /* Qbit.woz */,
 				325EB69A2401118300C6B4A4 /* Sneakers.woz */,
 				325EB6962401118200C6B4A4 /* Wavy Navy.woz */,
 				325EB69B2401118300C6B4A4 /* Xonix.woz */,
@@ -705,7 +703,7 @@
 				325EB6A62401118300C6B4A4 /* ProDOS_312.woz in Resources */,
 				325EB6AC2401118300C6B4A4 /* Xonix.woz in Resources */,
 				325EB67D23FBD43800C6B4A4 /* PrintChar21.ttf in Resources */,
-				325EB6A42401118300C6B4A4 /* qbit.woz in Resources */,
+				325EB6A42401118300C6B4A4 /* Qbit.woz in Resources */,
 				325EB68723FC707A00C6B4A4 /* Apple DOS 3.3 January 1983.woz in Resources */,
 				325EB64A23FBBACF00C6B4A4 /* Main.storyboard in Resources */,
 				325EB67A23FBC48400C6B4A4 /* spk_up.wav in Resources */,
@@ -747,7 +745,7 @@
 				325EB6A52401118300C6B4A4 /* ProDOS_312.woz in Resources */,
 				325EB6AB2401118300C6B4A4 /* Xonix.woz in Resources */,
 				325EB68623FC707A00C6B4A4 /* Apple DOS 3.3 January 1983.woz in Resources */,
-				325EB6A32401118300C6B4A4 /* qbit.woz in Resources */,
+				325EB6A32401118300C6B4A4 /* Qbit.woz in Resources */,
 				32439F8822ECD8AD0077AAE0 /* apple.rom in Resources */,
 				326ED2EF232D7A0000A41337 /* 6502_functional_test.bin in Resources */,
 				3262F37623E169F8008BDB95 /* spk_dn.wav in Resources */,
@@ -862,7 +860,6 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				32C4530B2331F7220000EBA1 /* 6502.c in Sources */,
 				32C4530C2331F7220000EBA1 /* ViewController.swift in Sources */,
 				32C4532F233345820000EBA1 /* MonitorView.swift in Sources */,
 				32C4530D2331F7220000EBA1 /* AppDelegate.swift in Sources */,
@@ -873,7 +870,6 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				32C4531D2331FED90000EBA1 /* 6502.c in Sources */,
 				32C4531E2331FED90000EBA1 /* ViewController.swift in Sources */,
 				32C45330233345820000EBA1 /* MonitorView.swift in Sources */,
 				32C4531F2331FED90000EBA1 /* AppDelegate.swift in Sources */,
diff --git a/A2Mac/AppDelegate.swift b/A2Mac/AppDelegate.swift
index cbd05e8..150f6fc 100644
--- a/A2Mac/AppDelegate.swift
+++ b/A2Mac/AppDelegate.swift
@@ -12,7 +12,12 @@ import Cocoa
 class AppDelegate: NSObject, NSApplicationDelegate {
 
 
-
+    @IBAction func Disk1_Selected(_ sender: NSMenuItem) {
+        if let menuIdentifier = sender.identifier {
+            woz_loadFile( Bundle.main.resourcePath, menuIdentifier.rawValue + ".woz" )
+        }
+    }
+    
     func applicationDidFinishLaunching(_ aNotification: Notification) {
         // Insert code here to initialize your application
     }
diff --git a/A2Mac/Base.lproj/Main.storyboard b/A2Mac/Base.lproj/Main.storyboard
index 8a33c27..9a5d390 100644
--- a/A2Mac/Base.lproj/Main.storyboard
+++ b/A2Mac/Base.lproj/Main.storyboard
@@ -600,6 +600,44 @@
                                     </items>
                                 </menu>
                             </menuItem>
+                            <menuItem title="Config" id="n97-rZ-OOP" userLabel="Config">
+                                <modifierMask key="keyEquivalentModifierMask"/>
+                                <menu key="submenu" title="Config" id="Xqf-B7-gCo">
+                                    <items>
+                                        <menuItem title="Disk 1" id="0NC-AF-e3z">
+                                            <modifierMask key="keyEquivalentModifierMask"/>
+                                            <menu key="submenu" title="Disk 1" id="lnc-y1-bUG">
+                                                <items>
+                                                    <menuItem title="Apple DOS 3.3 January 1983" identifier="Apple DOS 3.3 January 1983" id="KuV-6R-gyL">
+                                                        <modifierMask key="keyEquivalentModifierMask"/>
+                                                        <connections>
+                                                            <action selector="Disk1_Selected:" target="Voe-Tx-rLC" id="fFn-bN-fJA"/>
+                                                        </connections>
+                                                    </menuItem>
+                                                    <menuItem title="Donkey Kong" identifier="Donkey Kong" id="ero-Yw-Fxy">
+                                                        <modifierMask key="keyEquivalentModifierMask"/>
+                                                        <connections>
+                                                            <action selector="Disk1_Selected:" target="Voe-Tx-rLC" id="wwf-cD-Lv9"/>
+                                                        </connections>
+                                                    </menuItem>
+                                                    <menuItem title="Qbit" identifier="Qbit" id="3yK-n1-y7H">
+                                                        <modifierMask key="keyEquivalentModifierMask"/>
+                                                        <connections>
+                                                            <action selector="Disk1_Selected:" target="Voe-Tx-rLC" id="c8a-9v-oR4"/>
+                                                        </connections>
+                                                    </menuItem>
+                                                </items>
+                                            </menu>
+                                        </menuItem>
+                                        <menuItem title="Disk 2" id="yVX-3l-dbM">
+                                            <modifierMask key="keyEquivalentModifierMask"/>
+                                        </menuItem>
+                                        <menuItem title="Item 3" id="Y3v-20-h2Q">
+                                            <modifierMask key="keyEquivalentModifierMask"/>
+                                        </menuItem>
+                                    </items>
+                                </menu>
+                            </menuItem>
                             <menuItem title="View" id="H8h-7b-M4v">
                                 <modifierMask key="keyEquivalentModifierMask"/>
                                 <menu key="submenu" title="View" id="HyV-fh-RgO">
@@ -705,11 +743,11 @@
         <scene sceneID="hIz-AP-VOD">
             <objects>
                 <viewController id="XfG-lQ-9wD" customClass="ViewController" customModule="A2Mac" customModuleProvider="target" sceneMemberID="viewController">
-                    <view key="view" id="m2S-Jp-Qdl" customClass="MonitorView" customModule="A2Mac" customModuleProvider="target">
+                    <view key="view" canDrawConcurrently="YES" id="m2S-Jp-Qdl" customClass="MonitorView" customModule="A2Mac" customModuleProvider="target">
                         <rect key="frame" x="0.0" y="0.0" width="680" height="400"/>
                         <autoresizingMask key="autoresizingMask" flexibleMinX="YES" flexibleMaxX="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
                         <subviews>
-                            <textField verticalHuggingPriority="750" horizontalCompressionResistancePriority="250" mirrorLayoutDirectionWhenInternationalizing="never" textCompletion="NO" translatesAutoresizingMaskIntoConstraints="NO" id="iIF-Q5-Onc">
+                            <textField canDrawConcurrently="YES" verticalHuggingPriority="750" horizontalCompressionResistancePriority="250" mirrorLayoutDirectionWhenInternationalizing="never" textCompletion="NO" translatesAutoresizingMaskIntoConstraints="NO" id="iIF-Q5-Onc">
                                 <rect key="frame" x="0.0" y="0.0" width="592" height="400"/>
                                 <textFieldCell key="cell" lineBreakMode="truncatingTail" enabled="NO" allowsUndo="NO" sendsActionOnEndEditing="YES" state="on" baseWritingDirection="leftToRight" title="Display Background" drawsBackground="YES" id="cIa-Sd-4OZ">
                                     <font key="font" metaFont="system"/>
@@ -756,7 +794,7 @@
                                     <color key="backgroundColor" name="textBackgroundColor" catalog="System" colorSpace="catalog"/>
                                 </textFieldCell>
                             </textField>
-                            <customView translatesAutoresizingMaskIntoConstraints="NO" id="LlM-EV-ruZ" customClass="HiRes" customModule="A2Mac" customModuleProvider="target">
+                            <customView canDrawConcurrently="YES" translatesAutoresizingMaskIntoConstraints="NO" id="LlM-EV-ruZ" customClass="HiRes" customModule="A2Mac" customModuleProvider="target">
                                 <rect key="frame" x="16" y="8" width="568" height="384"/>
                             </customView>
                             <button verticalHuggingPriority="750" translatesAutoresizingMaskIntoConstraints="NO" id="mfd-12-bcR">
diff --git a/A2Mac/HiRes.swift b/A2Mac/HiRes.swift
index bfec12b..5a24b0b 100644
--- a/A2Mac/HiRes.swift
+++ b/A2Mac/HiRes.swift
@@ -560,10 +560,12 @@ class HiRes: NSView {
     //        self.hidden = videoMode.text == 1
         
 //        NSColor.green.setFill()
-        NSColor(calibratedRed: 0.0314, green: 0.635, blue: 0.071, alpha: 1.0).setStroke()
-
+//        NSColor(calibratedRed: 0.0314, green: 0.635, blue: 0.071, alpha: 1.0).setStroke()
+//        NSColor(calibratedRed: 0.05, green: 0.7, blue: 0.1, alpha: 1.0).setStroke()
+        NSColor.systemGreen.setStroke()
+        
         path.removeAllPoints()
-        path.lineWidth=0.7
+        path.lineWidth = 0.7
         path.move(to: NSPoint(x: 0, y: 0))
         
 //        path.appendRect(NSRect(x: 0, y: 0, width: 10, height: 10))
diff --git a/Resources/Qbit.woz b/Resources/Qbit.woz
new file mode 100644
index 0000000..b51cd1e
Binary files /dev/null and b/Resources/Qbit.woz differ
diff --git a/src/cpu/6502.c b/src/cpu/6502.c
index db23bfd..845cba0 100644
--- a/src/cpu/6502.c
+++ b/src/cpu/6502.c
@@ -897,7 +897,7 @@ void m6502_ColdReset( const char * bundlePath ) {
 
     
     // GAMES
-//woz_loadFile( bundlePath, "qbit.woz"); // Lode Runner, Hard Hat Mack, QBit, Crossfire, Heat Seaker, Flight Simulator
+//    woz_loadFile( bundlePath, "qbit.woz"); // Lode Runner, Hard Hat Mack, QBit, Crossfire, Heat Seaker, Flight Simulator
 //    woz_loadFile( bundlePath, "Donkey Kong.woz");
 
 /**///    woz_loadFile( bundlePath, "Crossfire.woz");
@@ -910,6 +910,7 @@ void m6502_ColdReset( const char * bundlePath ) {
     
     // SYSTEM
 /* Requires 64K *///    woz_loadFile( bundlePath, "ProDOS_312.woz");
+/* Requires Enhanced //e or later *///    woz_loadFile( bundlePath, "ProDOS_402_System.woz");
 
 //    woz_loadFile( bundlePath, "Merlin-8 v2.48 (DOS 3.3).woz");
     woz_loadFile( bundlePath, "Apple DOS 3.3 January 1983.woz");
diff --git a/src/cpu/6502.h b/src/cpu/6502.h
index 463195e..dc6d536 100644
--- a/src/cpu/6502.h
+++ b/src/cpu/6502.h
@@ -118,6 +118,7 @@ extern double mhz;
 
 #define fps 30
 
+extern void woz_loadFile( const char * bundlePath, const char * filename );
 extern void tst6502(void);
 extern void m6502_ColdReset( const char * bundlePath );
 extern void m6502_Run(void);
diff --git a/src/cpu/instructions/6502_instr_load_store.h b/src/cpu/instructions/6502_instr_load_store.h
index dae249a..2b57264 100644
--- a/src/cpu/instructions/6502_instr_load_store.h
+++ b/src/cpu/instructions/6502_instr_load_store.h
@@ -11,6 +11,7 @@
 #define __6502_INSTR_LOAD_STORE_H__
 
 #include <ctype.h>
+#include "../../dev/mem/mmio.h"
 
 /**
  LDA  Load Accumulator with Memory
@@ -112,6 +113,8 @@ INLINE void STR( uint8_t * dst, uint8_t src ) {
         else {
     //        printf("mmio write:[%04X] = %02X\n", addr, src);
     //        dst = Apple2_Dummy_Page;
+            
+            ioWrite( addr, src );
             return;
         }
     }
diff --git a/src/dev/disk/woz.c b/src/dev/disk/woz.c
index 3e78fdc..782cbb1 100644
--- a/src/dev/disk/woz.c
+++ b/src/dev/disk/woz.c
@@ -255,38 +255,40 @@ uint8_t woz_read() {
     m6502.clklast = m6502.clktime;
     
     uint16_t usedBytes = woz_trks[track].bytes_used < WOZ_TRACK_BYTE_COUNT ? woz_trks[track].bytes_used : WOZ_TRACK_BYTE_COUNT;
-
-    if ( clkelpased > 100 ) {
-//        printf("NEED SYNC : %llu\n", clkelpased);
-        bitOffset = (clkelpased >> 2) & 7;
-        trackOffset += ((clkelpased >> 5) +100) % usedBytes;
-        WOZread.data = woz_trks[track].data[trackOffset];
-    }
-
-    // to avoid infinite loop and to search for bit 7 high
-    for ( int i = 0; i < usedBytes * 8; i++ ) {
-        if ( ++bitOffset >= 8 ) {
-            bitOffset = 0;
-//                    if ( ++trackOffset >= WOZ_TRACK_BYTE_COUNT ) {
-//                        trackOffset = 0;
-//                    }
-            trackOffset++;
-            trackOffset %= usedBytes;
-
-//                    printf("offs:%u\n", trackOffset);
+    if ( usedBytes ) {
+        if ( clkelpased > 100 ) {
+    //        printf("NEED SYNC : %llu\n", clkelpased);
+            bitOffset = (clkelpased >> 2) & 7;
+            trackOffset += ((clkelpased >> 5) +100) % usedBytes;
             WOZread.data = woz_trks[track].data[trackOffset];
         }
-        
-        WOZread.shift16 <<= 1;
-        if ( WOZread.valid ) {
-            uint8_t byte = WOZread.shift;
-//                    printf("%02X ", byte);
-            WOZread.shift = 0;
-            if (outdev) fprintf(outdev, "byte: %02X\n", byte);
-            return byte;
+
+        // to avoid infinite loop and to search for bit 7 high
+        for ( int i = 0; i < usedBytes * 8; i++ ) {
+            if ( ++bitOffset >= 8 ) {
+                bitOffset = 0;
+    //                    if ( ++trackOffset >= WOZ_TRACK_BYTE_COUNT ) {
+    //                        trackOffset = 0;
+    //                    }
+                trackOffset++;
+                trackOffset %= usedBytes;
+
+    //                    printf("offs:%u\n", trackOffset);
+                WOZread.data = woz_trks[track].data[trackOffset];
+            }
+            
+            WOZread.shift16 <<= 1;
+            if ( WOZread.valid ) {
+                uint8_t byte = WOZread.shift;
+    //                    printf("%02X ", byte);
+                WOZread.shift = 0;
+                if (outdev) fprintf(outdev, "byte: %02X\n", byte);
+                return byte;
+            }
         }
+        if (outdev) fprintf(outdev, "TIME OUT!\n");
     }
-    if (outdev) fprintf(outdev, "TIME OUT!\n");
+    
     return rand();
 
 #endif // WOZ_REAL_SPIN
@@ -294,11 +296,11 @@ uint8_t woz_read() {
 }
 
 
-void woz_loadFile( const char * bundlePath, const char * filename ) {
+void woz_loadFile( const char * resourcePath, const char * filename ) {
     
     char fullpath[256];
     
-    strcpy(fullpath, bundlePath);
+    strcpy(fullpath, resourcePath);
     strcat(fullpath, "/");
     strcat(fullpath, filename);
     
diff --git a/src/dev/mem/mmio.h b/src/dev/mem/mmio.h
index 1124eca..2de96a2 100644
--- a/src/dev/mem/mmio.h
+++ b/src/dev/mem/mmio.h
@@ -499,8 +499,12 @@ INLINE void ioWrite( uint16_t addr, uint8_t val ) {
     //    printf("mmio:%04X\n", addr);
     switch (addr) {
         case io_KBD:
-            return;
+            break;
             
+        case io_KBDSTRB:
+            RAM[io_KBD] &= 0x7F;
+            break;
+
         default:
             break;
     }