diff --git a/assembler.js b/assembler.js
index c765f01..874655c 100644
--- a/assembler.js
+++ b/assembler.js
@@ -38,8 +38,11 @@ const mnemonics2opcodes = {
 function decodeInstructions(line) {
   let lines = line.split(/\n/); // returns an array of lines
 
-  let machineCode = new Array(INITIAL_IP_ADDRESS).fill(0);
-  machineCode[POINTER_TO_START_OF_DISPLAY_MEM] = START_OF_DISPLAY_MEM;
+  //let machineCode = new Array(INITIAL_IP_ADDRESS).fill(0);
+  let machineCode = new Array(256).fill(0);
+  dbgExec(2, () => logMemory(new Uint8Array(machineCode)));
+  machineCode[POINTER_TO_DISPLAY] = DISPLAY_ADDR;
+  machineCode[POINTER_TO_KEYPAD]  = KEYPAD_ADDR;
 
   let labels = {};
   let constants = {};
@@ -174,8 +177,9 @@ function decodeInstructions(line) {
     // DECODE!
     const op = mnemonics2opcodes[opName][addressingMode];
 
-    machineCode.push(op);
-    machineCode.push(arg_num);
+    machineCode[IP] = op;
+    machineCode[IP+1] = arg_num;
+
     dbg(3, `IP: $${num2hex(IP)}, new code: $${num2hex(op)} $${num2hex(arg_num)}`);
     IP += 2;
     dbgGroupEnd(1, 'Input line');
@@ -198,10 +202,6 @@ function decodeInstructions(line) {
     }
   }
 
-  // Add an END at the end
-  machineCode.push('0');
-  machineCode.push('0'); 
-
   return new Uint8Array(machineCode);
 }