diff --git a/doc/notes.txt b/doc/notes.txt
index 272f69d6..219d0539 100644
--- a/doc/notes.txt
+++ b/doc/notes.txt
@@ -94,6 +94,7 @@ TODO:
 - stego shareable images (http://pico-8.wikia.com/wiki/P8PNGFileFormat)
 - https://makecode.com/language?
 - show .map file in listings?
+- open ROM from URL?
 
 
 WEB WORKER FORMAT
@@ -191,4 +192,19 @@ intermediate file could still be edited
 switch between hex/graphic editor? (palettes should edit via hex)
 final display types: number, color, sprite, etc
 CHR editor has palette selector, obj selector
+individual objects in single file or multiple files?
+RLE compression
+
+Types
+- byte
+- RGBA color
+- structured object
+  - metasprite
+  - metatile
+  - level actor
+- bitmap
+- array of stuff, array can have a shape (width,height) like numpy
+Mappers can refer to multiple objs
+Slice (window) of array for selections
+
 
diff --git a/embed.html b/embed.html
index 655ba652..1e5edc35 100644
--- a/embed.html
+++ b/embed.html
@@ -71,111 +71,12 @@ function require(modname) {
 <script src="gen/baseplatform.js"></script>
 <script src="gen/audio.js"></script>
 <script src="gen/recorder.js"></script>
+<script src="gen/embedui.js"></script>
 
 <script src="lib/liblzg.js"></script>
 
 <script>
-
-window.Javatari.AUTO_START = false;
-var PLATFORMS = exports.PLATFORMS;
-var platform, platform_id;
-
-var _qs = (function (a) {
-    if (!a || a.length == 0)
-        return {};
-    var b = {};
-    for (var i = 0; i < a.length; ++i) {
-        var p = a[i].split('=', 2);
-        if (p.length == 1)
-            b[p[0]] = "";
-        else
-            b[p[0]] = decodeURIComponent(p[1].replace(/\+/g, " "));
-    }
-    return b;
-})(window.location.search.substr(1).split('&'));
-
-// catch errors
-function installErrorHandler() {
-  if (typeof window.onerror == "object") {
-      window.onerror = function (msgevent, url, line, col, error) {
-        ga('send', 'exception', {
-          'exDescription': msgevent + " " + url + " " + " " + line + ":" + col + ", " + error,
-          'exFatal': true
-        });
-        //alert(msgevent+"");
-      };
-  }
-}
-
-function uninstallErrorHandler() {
-  window.onerror = null;
-}
-
-function addPageFocusHandlers() {
-  var hidden = false;
-  document.addEventListener("visibilitychange", function() {
-    if (document.visibilityState == 'hidden' && platform.isRunning()) {
-      platform.pause();
-      hidden = true;
-    } else if (document.visibilityState == 'visible' && hidden) {
-      platform.resume();
-      hidden = false;
-    }
-  });
-  $(window).on("focus", function() {
-    if (hidden) {
-      platform.resume();
-      hidden = false;
-    }
-  });
-  $(window).on("blur", function() {
-    if (platform.isRunning()) {
-      platform.pause();
-      hidden = true;
-    }
-  });
-}
-
-function startPlatform(qs) {
-  if (!PLATFORMS[platform_id]) throw Error("Invalid platform '" + platform_id + "'.");
-  platform = new PLATFORMS[platform_id]($("#emulator")[0]);
-  platform.start();
-  var title = qs['n'] || 'Game';
-  var lzgrom = stringToByteArray(atob(qs['r']));
-  var rom = new lzgmini().decode(lzgrom);
-  console.log(rom.length + ' bytes');
-  platform.loadROM(title, rom);
-  platform.resume();
-  return true;
-}
-
-function loadPlatform(qs) {
-  if (qs.data) qs = qs.data;
-  platform_id = qs['p'];
-  if (!platform_id) throw('No platform variable!');
-  var scriptfn = 'gen/platform/' + platform_id.split(/[.-]/)[0] + '.js';
-  loadScript(scriptfn, () => {
-    console.log("loaded platform", platform_id);
-    startPlatform(qs);
-  });
-}
-
-function loadScript(scriptfn, onload) {
-  var script = document.createElement('script');
-  script.onload = onload;
-  script.src = scriptfn;
-  document.getElementsByTagName('head')[0].appendChild(script);
-}
-
-// start
-function startEmbed() {
-  installErrorHandler();
-  window.addEventListener("message", loadPlatform, false);
-  if (_qs['p']) loadPlatform(_qs);
-}
-
 startEmbed();
-
 </script>
 
 </body>
diff --git a/src/embedui.ts b/src/embedui.ts
new file mode 100644
index 00000000..7bf1f5e2
--- /dev/null
+++ b/src/embedui.ts
@@ -0,0 +1,108 @@
+
+window['Javatari'].AUTO_START = false;
+
+import { PLATFORMS } from "./emu";
+import { Platform } from "./baseplatform";
+import { stringToByteArray } from "./util";
+
+export var platform_id : string;	// platform ID string
+export var platform : Platform;	// platform object
+
+// external libs (TODO)
+declare var ga, lzgmini;
+
+var _qs = (function (a) {
+    if (!a || a.length == 0)
+        return {};
+    var b = {};
+    for (var i = 0; i < a.length; ++i) {
+        var p = a[i].split('=', 2);
+        if (p.length == 1)
+            b[p[0]] = "";
+        else
+            b[p[0]] = decodeURIComponent(p[1].replace(/\+/g, " "));
+    }
+    return b;
+})(window.location.search.substr(1).split('&'));
+
+// catch errors
+function installErrorHandler() {
+  if (typeof window.onerror == "object") {
+      window.onerror = function (msgevent, url, line, col, error) {
+        ga('send', 'exception', {
+          'exDescription': msgevent + " " + url + " " + " " + line + ":" + col + ", " + error,
+          'exFatal': true
+        });
+        //alert(msgevent+"");
+      };
+  }
+}
+
+function uninstallErrorHandler() {
+  window.onerror = null;
+}
+
+function addPageFocusHandlers() {
+  var hidden = false;
+  document.addEventListener("visibilitychange", function() {
+    if (document.visibilityState == 'hidden' && platform.isRunning()) {
+      platform.pause();
+      hidden = true;
+    } else if (document.visibilityState == 'visible' && hidden) {
+      platform.resume();
+      hidden = false;
+    }
+  });
+  $(window).on("focus", function() {
+    if (hidden) {
+      platform.resume();
+      hidden = false;
+    }
+  });
+  $(window).on("blur", function() {
+    if (platform.isRunning()) {
+      platform.pause();
+      hidden = true;
+    }
+  });
+}
+
+function startPlatform(qs) {
+  if (!PLATFORMS[platform_id]) throw Error("Invalid platform '" + platform_id + "'.");
+  platform = new PLATFORMS[platform_id]($("#emulator")[0]);
+  platform.start();
+  var title = qs['n'] || 'Game';
+  var lzgvar = qs['r'];
+  var lzgrom = stringToByteArray(atob(lzgvar));
+  var rom = new lzgmini().decode(lzgrom);
+  console.log(rom.length + ' bytes');
+  platform.loadROM(title, rom);
+  platform.resume();
+  return true;
+}
+
+function loadPlatform(qs) {
+  if (qs.data) qs = qs.data;
+  platform_id = qs['p'];
+  if (!platform_id) throw('No platform variable!');
+  var scriptfn = 'gen/platform/' + platform_id.split(/[.-]/)[0] + '.js';
+  loadScript(scriptfn, () => {
+    console.log("loaded platform", platform_id);
+    startPlatform(qs);
+  });
+}
+
+function loadScript(scriptfn, onload) {
+  var script = document.createElement('script');
+  script.onload = onload;
+  script.src = scriptfn;
+  document.getElementsByTagName('head')[0].appendChild(script);
+}
+
+// start
+export function startEmbed() {
+  installErrorHandler();
+  window.addEventListener("message", loadPlatform, false);
+  if (_qs['p']) loadPlatform(_qs);
+}
+