diff --git a/022.photons_bootloader/README.md b/022.photons_bootloader/README.md
index 3f21703..915e596 100644
--- a/022.photons_bootloader/README.md
+++ b/022.photons_bootloader/README.md
@@ -1,7 +1,21 @@
 Photon's bootloader
 ===================
 
+In this example we take [020.shrinkler](../020.shrinkler) and convert it to use [Photon's bootloader](http://coppershade.org/asmskool/SOURCES/Photon-snippets/DDE5-BootLoader.S).
+
+I hacked the [boot loader code](../shared/hardware_bootloader.s) just a little bit. Firstly I think some of the vasm optimisations messed with some of the code offsets that are assumed by Photon's code.  Secondly I modified it to be compatible with my previous bootloader.
+
+The bootblock code is in [../shared/hardware_bootblock.s](../shared/hardware_bootblock.s), and will be the default bootblock I use going forward.
+
+A new [Makefile](Makefile) config option has been added:
+
+```
+USERSTACK_ADDRESS=7fffc
+```
+
+Luckily the bootloader and shrinkler code still fit in the bootblock :-)
+
 try it
 ------
-  * [Download disk image](bin/shrinker.adf?raw=true)
-  * <a href="http://alpine9000.github.io/ScriptedAmigaEmulator/#amiga_examples/shrinkler.adf" target="_blank">Run in SAE</a>
+  * [Download disk image](bin/photons_bootloader.adf?raw=true)
+  * <a href="http://alpine9000.github.io/ScriptedAmigaEmulator/#amiga_examples/photons_bootloader.adf" target="_blank">Run in SAE</a>