diff --git a/assets/!BOOTSEC b/assets/!BOOTSEC
new file mode 100644
index 0000000..d014ab6
--- /dev/null
+++ b/assets/!BOOTSEC
@@ -0,0 +1 @@
+let p=_BIOS.FIRST_BOOTABLE_PORT;com.sendMessage(p[0],'OPENR"tvdos/TVDOS.SYS",'+p[1]);let r=com.getStatusCode(p[0]);if(0==r)if(com.sendMessage(p[0],"READ"),r=com.getStatusCode([0]),0==r){let g=com.pullMessage(p[0]);eval(g)}else println("I/O Error");else println("TVDOS.SYS not found");
\ No newline at end of file
diff --git a/assets/bios1.js b/assets/bios1.js
index d7dc9e1..c193e58 100644
--- a/assets/bios1.js
+++ b/assets/bios1.js
@@ -82,4 +82,5 @@ Object.freeze(_BIOS);
 
 ///////////////////////////////////////////////////////////////////////////////
 
+// TODO load a bootsector using 'LOADBOOT'
 con.move(4,1);
\ No newline at end of file
diff --git a/assets/bootsec_source.js b/assets/bootsec_source.js
new file mode 100644
index 0000000..05ffb6a
--- /dev/null
+++ b/assets/bootsec_source.js
@@ -0,0 +1,17 @@
+// load TVDOS.SYS
+let p = _BIOS.FIRST_BOOTABLE_PORT;
+com.sendMessage(p[0], 'OPENR"tvdos/TVDOS.SYS",'+p[1]);
+let r = com.getStatusCode(p[0]);
+if (r == 0){
+    com.sendMessage(p[0], "READ");
+    r = com.getStatusCode([0]);
+    if (r == 0) {
+        let g=com.pullMessage(p[0]);
+        eval(g);
+        0;
+    }
+    else
+        println("I/O Error");
+}
+else
+    println("TVDOS.SYS not found");
diff --git a/assets/tvdos/TVDOS.SYS b/assets/tvdos/TVDOS.SYS
index 37f29e8..7a7893e 100644
--- a/assets/tvdos/TVDOS.SYS
+++ b/assets/tvdos/TVDOS.SYS
@@ -1,11 +1,11 @@
-// Boot script
+// define TVDOS
 var _TVDOS = {};
 _TVDOS.VERSION = "1.0";
 _TVDOS.DRIVES = {}; // Object where key-value pair is <drive-letter> : [serial-port, drive-number]
 // actually figure out the drive letter association
 // Drive A is always the device we're currently on
 _TVDOS.DRIVES["A"] = _BIOS.FIRST_BOOTABLE_PORT;
-
+//TODO
 
 
 Object.freeze(_TVDOS);
@@ -53,4 +53,16 @@ filesystem.readAll = function(driveLetter) {
     }
     return com.pullMessage(port[0]);
 };
-Object.freeze(filesystem);
\ No newline at end of file
+Object.freeze(filesystem);
+
+///////////////////////////////////////////////////////////////////////////////
+
+// install other stuffs
+filesystem.open("A", "tvdos/gl.js", "R");
+var GL = eval(filesystem.readAll("A"));
+
+///////////////////////////////////////////////////////////////////////////////
+
+// Boot script
+filesystem.open("A", "tvdos/command.js", "R");
+eval(filesystem.readAll("A"));
diff --git a/assets/tvdos/flsh.js b/assets/tvdos/flsh.js
index 75756e8..8b0f957 100644
--- a/assets/tvdos/flsh.js
+++ b/assets/tvdos/flsh.js
@@ -7,11 +7,11 @@ const welcome_text = "TSVM Disk Operating System, version " + _TVDOS.VERSION;
 function print_prompt_text() {
     // oh-my-zsh-like prompt
     con.color_pair(239,161);
-    print(" "+CURRENT_DRIVE);
+    print(" "+CURRENT_DRIVE+":");
     con.color_pair(161,253);
     con.addch(16);
     con.color_pair(0,253);
-    print("\\"+shell_pwd.join("\\"));
+    print(" \\"+shell_pwd.join("\\")+" ");
     con.color_pair(253,255);
     con.addch(16);
     con.addch(32);
diff --git a/assets/tvdos/gl.js b/assets/tvdos/gl.js
index fd9d625..9b7e280 100644
--- a/assets/tvdos/gl.js
+++ b/assets/tvdos/gl.js
@@ -101,4 +101,4 @@ GL.drawSpriteOver = function(sheet, xi, yi, x, y) {
     }
 };
 
-Object.freeze(GL);
+Object.freeze(GL); // this returns frozen 'GL'
diff --git a/src/net/torvald/tsvm/VMGUI.kt b/src/net/torvald/tsvm/VMGUI.kt
index f7eb732..f0c2ecf 100644
--- a/src/net/torvald/tsvm/VMGUI.kt
+++ b/src/net/torvald/tsvm/VMGUI.kt
@@ -60,30 +60,22 @@ class VMGUI(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter()
         val bios = fr1.readText()
         fr1.close()
 
-
-        val fr2 = FileReader("./assets/tvdos/gl.js")
-        val tvgl = fr2.readText()
-        fr2.close()
-
-        val fr3 = FileReader("./assets/tvdos/TVDOS.SYS")
-        val tvknl = fr3.readText()
-        fr3.close()
-
-
         //val fr = FileReader("./assets/tvdos/command.js")
         //val fr = FileReader("./assets/zippytest.js")
         //val fr = FileReader("./assets/serialtest.js")
         //val fr = FileReader("./assets/tvdos/fsh.js")
-        val fr = FileReader("./assets/tvdos/flsh.js")
+        //val fr = FileReader("./assets/tvdos/flsh.js")
         //val fr = FileReader("./assets/tbas/basic.js")
         //val fr = FileReader("./assets/jscon.js")
+        val fr = FileReader("./assets/!BOOTSEC")
         val prg = fr.readText()
         fr.close()
 
         vmRunner = VMRunnerFactory(vm, "js")
         coroutineJob = GlobalScope.launch {
-            vmRunner.evalGlobal("$bios\n$tvknl\n$tvgl")
-            vmRunner.executeCommand(prg)
+            //vmRunner.evalGlobal("$bios")
+            //vmRunner.executeCommand(prg)
+            vmRunner.executeCommand("$bios\n$prg")
         }
     }
 
diff --git a/src/net/torvald/tsvm/peripheral/IOSpace.kt b/src/net/torvald/tsvm/peripheral/IOSpace.kt
index e8e817f..b3bda14 100644
--- a/src/net/torvald/tsvm/peripheral/IOSpace.kt
+++ b/src/net/torvald/tsvm/peripheral/IOSpace.kt
@@ -5,6 +5,7 @@ import com.badlogic.gdx.InputProcessor
 import net.torvald.UnsafeHelper
 import net.torvald.tsvm.VM
 import net.torvald.util.CircularArray
+import java.io.File
 import kotlin.experimental.and
 
 class IOSpace(val vm: VM) : PeriBase, InputProcessor {
@@ -39,7 +40,7 @@ class IOSpace(val vm: VM) : PeriBase, InputProcessor {
 
     init {
         blockTransferPorts[1].attachDevice(TestFunctionGenerator())
-        blockTransferPorts[0].attachDevice(TestDiskDrive(0))
+        blockTransferPorts[0].attachDevice(TestDiskDrive(0, File("assets/")))
     }
 
     private fun composeBlockTransferStatus(portno: Int): Int {
diff --git a/src/net/torvald/tsvm/peripheral/TestDiskDrive.kt b/src/net/torvald/tsvm/peripheral/TestDiskDrive.kt
index 06776b1..2ce1c48 100644
--- a/src/net/torvald/tsvm/peripheral/TestDiskDrive.kt
+++ b/src/net/torvald/tsvm/peripheral/TestDiskDrive.kt
@@ -6,7 +6,7 @@ import java.io.File
 import java.io.IOException
 import java.util.*
 
-class TestDiskDrive(private val driveNum: Int) : BlockTransferInterface(false, true) {
+class TestDiskDrive(private val driveNum: Int, theRootPath: File? = null) : BlockTransferInterface(false, true) {
 
     companion object {
         const val STATE_CODE_STANDBY = 0
@@ -41,7 +41,7 @@ class TestDiskDrive(private val driveNum: Int) : BlockTransferInterface(false, t
         return sb.toByteArray()
     }
 
-    private val rootPath = File("test_assets/test_drive_$driveNum")
+    private val rootPath = theRootPath ?: File("test_assets/test_drive_$driveNum")
 
     private var fileOpen = false
     private var fileOpenMode = -1 // 1: 'W", 2: 'A'