diff --git a/demo/intelhex.ts b/demo/intelhex.ts
index ba5d6c8..3694ca4 100644
--- a/demo/intelhex.ts
+++ b/demo/intelhex.ts
@@ -5,11 +5,15 @@
  * Copyright (C) 2019, Uri Shaked
  */
 
-export function loadHex(source: string, target: Uint8Array) {
+export function loadHex(source: string, target: Uint8Array, baseAddress: number = 0) {
+  let highAddressBytes = 0;
   for (const line of source.split('\n')) {
+    if (line[0] === ':' && line.substr(7, 2) === '04') {
+      highAddressBytes = parseInt(line.substr(9, 4), 16);
+    }
     if (line[0] === ':' && line.substr(7, 2) === '00') {
       const bytes = parseInt(line.substr(1, 2), 16);
-      const addr = parseInt(line.substr(3, 4), 16);
+      const addr = ((highAddressBytes << 16) | parseInt(line.substr(3, 4), 16)) - baseAddress;
       for (let i = 0; i < bytes; i++) {
         target[addr + i] = parseInt(line.substr(9 + i * 2, 2), 16);
       }