diff --git a/src/common/baseplatform.ts b/src/common/baseplatform.ts
index e7af32e6..9c8190d7 100644
--- a/src/common/baseplatform.ts
+++ b/src/common/baseplatform.ts
@@ -13,6 +13,7 @@ import { SampledAudio } from "./audio";
 import { ProbeRecorder } from "./recorder";
 import { BaseWASMMachine } from "./wasmplatform";
 import { CPU6809 } from "./cpu/6809";
+import { _MOS6502 } from "./cpu/MOS6502";
 
 ///
 
@@ -448,7 +449,7 @@ export abstract class Base6502Platform extends BaseDebugPlatform {
   abstract readAddress(addr:number) : number;
 
   newCPU(membus : MemoryBus) {
-    var cpu = new jt.M6502();
+    var cpu = new _MOS6502();
     cpu.connectBus(membus);
     return cpu;
   }
diff --git a/src/common/cpu/MOS6502.ts b/src/common/cpu/MOS6502.ts
index 33362d8e..2f516999 100644
--- a/src/common/cpu/MOS6502.ts
+++ b/src/common/cpu/MOS6502.ts
@@ -3,7 +3,7 @@ import { CPU, Bus, ClockBased, SavesState, Interruptable } from "../devices";
 
 // Copyright 2015 by Paulo Augusto Peccin. See license.txt distributed with this file.
 
-var _MOS6502 = function() {
+export var _MOS6502 = function() {
     var self = this;
 
     this.powerOn = function() {
diff --git a/src/ide/ui.ts b/src/ide/ui.ts
index 289c49b1..4551dfe9 100644
--- a/src/ide/ui.ts
+++ b/src/ide/ui.ts
@@ -30,6 +30,7 @@ declare var $ : JQueryStatic; // use browser jquery
 
 interface UIQueryString {
   platform? : string;
+  options?: string;
   repo? : string;
   file? : string;
   electron? : string;
@@ -2213,7 +2214,9 @@ function installGAHooks() {
 
 async function startPlatform() {
   if (!PLATFORMS[platform_id]) throw Error("Invalid platform '" + platform_id + "'.");
-  platform = new PLATFORMS[platform_id]($("#emuscreen")[0]);
+  let emudiv = $("#emuscreen")[0];
+  let options = decodeQueryString(qs.options || '');
+  platform = new PLATFORMS[platform_id](emudiv, options);
   setPlatformUI();
   stateRecorder = new StateRecorderImpl(platform);
   PRESETS = platform.getPresets ? platform.getPresets() : [];
diff --git a/src/platform/vector.ts b/src/platform/vector.ts
index ba2c5ed0..2df13cc2 100644
--- a/src/platform/vector.ts
+++ b/src/platform/vector.ts
@@ -270,7 +270,7 @@ var AtariColorVectorPlatform = function(mainElement) {
         clock++;
         if (--nmicount == 0) {
           //console.log("NMI", cpu.saveState());
-          var n = cpu.setIRQAndWait(); // TODO: only if I flag set
+          var n = cpu.setIRQ(); // TODO: only if I flag set
           clock += n;
           nmicount = cpuCyclesPerNMI - n;
           //console.log(n, clock, nmicount);
diff --git a/src/platform/williams.ts b/src/platform/williams.ts
index 7c2275ca..777e9cb1 100644
--- a/src/platform/williams.ts
+++ b/src/platform/williams.ts
@@ -432,6 +432,10 @@ var WilliamsPlatform = function(mainElement, proto, isDefender) {
   ] } };
 }
 
+var Williams6809Platform = function(mainElement) {
+  this.__proto__ = new WilliamsPlatform(mainElement, null, false);
+}
+
 var WilliamsZ80Platform = function(mainElement) {
   this.__proto__ = new WilliamsPlatform(mainElement, BaseZ80Platform, false);
 
@@ -462,7 +466,7 @@ var WilliamsDefenderPlatform = function(mainElement) {
 ] } };
 }
 
-PLATFORMS['williams'] = WilliamsPlatform;
+PLATFORMS['williams'] = Williams6809Platform;
 PLATFORMS['williams-defender'] = WilliamsDefenderPlatform;
 PLATFORMS['williams-z80'] = WilliamsZ80Platform;
 
diff --git a/src/worker/lib/vector-ataricolor/crt0.o b/src/worker/lib/vector-ataricolor/crt0.o
index 26a68713..a904d800 100644
Binary files a/src/worker/lib/vector-ataricolor/crt0.o and b/src/worker/lib/vector-ataricolor/crt0.o differ
diff --git a/src/worker/lib/vector-ataricolor/crt0.s b/src/worker/lib/vector-ataricolor/crt0.s
index 9dc585df..6ebaa318 100644
--- a/src/worker/lib/vector-ataricolor/crt0.s
+++ b/src/worker/lib/vector-ataricolor/crt0.s
@@ -8,7 +8,6 @@
         .export         __STARTUP__ : absolute = 1      ; Mark as startup
         .import         zerobss, callmain
         .import         initlib, donelib, copydata
-        .import         exit
         .import         __PRGRAM_START__, __PRGRAM_SIZE__   ; Linker generated
 ;        .import         __STACKSIZE__                   ; Linker generated
 
@@ -30,7 +29,7 @@ start:
 _exit:  pha
         jsr     donelib
         pla
-        jmp     exit
+        jmp     start
 
 nmi:
 	inc	$0