diff --git a/atrcopy/fstbt.py b/atrcopy/fstbt.py
new file mode 100644
index 0000000..25943f5
--- /dev/null
+++ b/atrcopy/fstbt.py
@@ -0,0 +1,4 @@
+# generated file - recompile fstbt.s to make changes
+
+# append jump target (lo, hi) and sector address list before saving to disk
+fstbt = b"\x01\xa8\x8dP\xc0\x8dR\xc0\x8dW\xc0\xee\x0f\x08\xadl\x08\xc9\xc0\xf0U\xc9\xd0\xf0\xf2\xc9\xd1\xd0\x05\x8dT\xc0\xf0\xe9\xc9\xd2\xd0\x05\x8dU\xc0\xf0\xe0\x85'\xc8\xc0\x10\x90\t\xf0\x05 M\x08\xa8,\xa0\x01\x84=\xc8\xa5'\xf0\xc9\x8a {\xf8\t\xc0H\xa9[H`\xe6A\x06@ U\x08\x18 Z\x08\xe6@\xa5@)\x03*\x05+\xa8\xb9\x80\xc0\xa90L\xa8\xfcL"
diff --git a/atrcopy/standard_delivery.py b/atrcopy/standard_delivery.py
index 1ecacfe..43a06d6 100644
--- a/atrcopy/standard_delivery.py
+++ b/atrcopy/standard_delivery.py
@@ -139,18 +139,11 @@ class StandardDeliveryImage(DiskImageBase):
 
         return dsk
 
-
-# fast boot code minus final jump address and sector address table
-fstbt_64k = b'\x01\xa8\xee\x06\x08\xadM\x08\xc9\xc0\xf0?\x85\x27\xc8\xc0\x10\x90\t\xf0\x05 .\x08\xa8,\xa0\x01\x84=\xc8\xa5\x27\xf0\xdf\x8a {\xf8\t\xc0H\xa9[H`\xe6A\x06@ 6\x08\x18 ;\x08\xe6@\xa5@)\x03*\x05+\xa8\xb9\x80\xc0\xa90L\xa8\xfcL'
-
-fstbt_64k_hgr = b'\x01\xa8,P\xc0,R\xc0,W\xc0\xee\x0f\x08\xadV\x08\xc9\xc0\xf0?\x85\x27\xc8\xc0\x10\x90\t\xf0\x05 7\x08\xa8,\xa0\x01\x84=\xc8\xa5\x27\xf0\xdf\x8a {\xf8\t\xc0H\xa9[H`\xe6A\x06@ ?\x08\x18 D\x08\xe6@\xa5@)\x03*\x05+\xa8\xb9\x80\xc0\xa90L\xa8\xfcL'
-
-fstbt_64k_trigger = b'\x01\xa8\x8dP\xc0\x8dR\xc0\x8dW\xc0\xee\x0f\x08\xadl\x08\xc9\xc0\xf0U\xc9\xd0\xf0\xf2\xc9\xd1\xd0\x05\x8dT\xc0\xf0\xe9\xc9\xd2\xd0\x05\x8dU\xc0\xf0\xe0\x85\x27\xc8\xc0\x10\x90\t\xf0\x05 M\x08\xa8,\xa0\x01\x84=\xc8\xa5\x27\xf0\xc9\x8a {\xf8\t\xc0H\xa9[H`\xe6A\x06@ U\x08\x18 Z\x08\xe6@\xa5@)\x03*\x05+\xa8\xb9\x80\xc0\xa90L\xa8\xfcL'
+from . fstbt import fstbt
 
 def get_fstbt_code(data, address_list, run_addr):
-    code = fstbt_64k_trigger
-    pointer = len(code)
-    data[0:pointer] = np.fromstring(code, dtype=np.uint8)
+    pointer = len(fstbt)
+    data[0:pointer] = np.fromstring(fstbt, dtype=np.uint8)
     hi, lo = divmod(run_addr, 256)
     data[pointer:pointer + 2] = (lo, hi)
     address_list.append(0xc0)  # last sector flag