diff --git a/presets/coleco/bios.c b/presets/coleco/bios.c
new file mode 100644
index 00000000..6affaafa
--- /dev/null
+++ b/presets/coleco/bios.c
@@ -0,0 +1,45 @@
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "cv.h"
+#include "cvu.h"
+
+#define DEFINE_BIOS_FN(name,address) \
+int name() { __asm call address __endasm; }
+
+DEFINE_BIOS_FN(cvbios_skill_screen, 0x1f7c)
+//DEFINE_BIOS_FN(cvbios_read_ctl, 0x1f79)
+  
+int cvbios_read_left_joystick() {
+  __asm
+    ld hl,#0x0000
+    jp 0x1f79
+  __endasm;
+}
+
+int cvbios_read_right_joystick() {
+  __asm
+    ld hl,#0x0100
+    jp 0x1f79
+  __endasm;
+}
+
+const char* const HEX = "0123456789ABCDEF";
+  
+void main() {
+  // load BIOS-friendly stack address
+  __asm
+    ld sp,#0x73b9
+  __endasm;
+  // call BIOS
+  cvbios_skill_screen();
+  // loop and read joystick
+  do {
+    int ctl = cvbios_read_left_joystick();
+    cvu_voutb(HEX[(ctl>>0)&0xf], 0x1800 + 3);
+    cvu_voutb(HEX[(ctl>>4)&0xf], 0x1800 + 2);
+    cvu_voutb(HEX[(ctl>>8)&0xf], 0x1800 + 1);
+    cvu_voutb(HEX[(ctl>>12)&0xf], 0x1800 + 0);
+  } while(1) ;
+}
diff --git a/src/emu.js b/src/emu.js
index dfc853e9..8c9c3cd8 100644
--- a/src/emu.js
+++ b/src/emu.js
@@ -874,9 +874,16 @@ var BaseMAMEPlatform = function() {
   var video;
   var preload_files;
   var running = false;
+  var console_vars = {};
+  var console_varname;
 
+  this.luareset = function() {
+    console_vars = {};
+  }
+
+  // http://docs.mamedev.org/techspecs/luaengine.html
   this.luacall = function(s) {
-    //console.log(s);
+    console_varname = null;
     Module.ccall('_Z13js_lua_stringPKc', 'void', ['string'], [s+""]);
   }
 
@@ -906,6 +913,18 @@ var BaseMAMEPlatform = function() {
     return running;
   }
 
+  function bufferConsoleOutput(s) {
+    if (!s) return;
+    if (s.startsWith(">>>")) {
+      console_varname = s.length > 3 ? s.slice(3) : null;
+      if (console_varname) console_vars[console_varname] = [];
+    } else if (console_varname) {
+      console_vars[console_varname].push(s);
+    } else {
+      console.log(s);
+    }
+  }
+
   this.startModule = function(mainElement, opts) {
     romfn = opts.romfn;
     if (!romdata) romdata = new RAM(opts.romsize).mem;
@@ -920,7 +939,7 @@ var BaseMAMEPlatform = function() {
     window.Module = {
       arguments: [opts.driver, '-verbose', '-window', '-nokeepaspect', '-resolution', canvas.width+'x'+canvas.height, '-cart', romfn],
       screenIsReadOnly: true,
-      print: function (text) { console.log(text); },
+      print: bufferConsoleOutput,
       canvas:video.canvas,
       doNotCaptureKeyboard:true,
       keyboardListeningElement:video.canvas,
@@ -985,4 +1004,33 @@ var BaseMAMEPlatform = function() {
     }
   }
 
+  this.saveState = function() {
+    this.luareset();
+    this.luacall('cpu = manager:machine().devices[":maincpu"]\nfor k,v in pairs(cpu.state) do print(">>>cpu_"..k); print(v.value) end');
+    var state = {c:{}};
+    for (var k in console_vars) {
+      if (k.startsWith("cpu_")) {
+        var v = parseInt(console_vars[k][0]);
+        state.c[k.slice(4)] = v;
+      }
+    }
+    // TODO
+    return state;
+  }
+
+  var initluavars=false;
+
+  this.readAddress = function(a) {
+    if (!initluavars) {
+      self.luacall('cpu = manager:machine().devices[":maincpu"]\nmem = cpu.spaces["program"]\n')
+      initluavars = true;
+    }
+    self.luacall('print(">>>v"); print(mem:read_u8(' + a + '))');
+    return parseInt(console_vars.v[0]);
+  }
+
+  this.getDebugCallback = function() {
+    // TODO
+  }
+
 }
diff --git a/src/platform/coleco.js b/src/platform/coleco.js
index 72a1d59c..678df996 100644
--- a/src/platform/coleco.js
+++ b/src/platform/coleco.js
@@ -8,6 +8,7 @@
 // http://www.theadamresource.com/manuals/technical/Jeffcoleco.html
 // http://bifi.msxnet.org/msxnet//tech/tms9918a.txt
 // http://www.colecovision.dk/tools.htm?refreshed
+// http://www.theadamresource.com/manuals/technical/ColecoVision%20Coding%20Guide.pdf
 
 var ColecoVision_PRESETS = [
   {id:'text.c', name:'Text Mode'},
@@ -201,13 +202,6 @@ var ColecoVisionMAMEPlatform = function(mainElement) {
       romfn:'/emulator/cart.rom',
       romsize:0x8000,
       preInit:function(_self) {
-        /*
-        console.log("Writing BIOS");
-        var dir = '/roms/coleco';
-        FS.mkdir('/roms');
-        FS.mkdir(dir);
-        FS.writeFile(dir + "/313 10031-4005 73108a.u2", COLECO_BIOS, {encoding:'binary'});
-        */
       },
     });
   }