More info about updates

diff --git a/api/update.gamestickservices.net/check.php.rst b/api/update.gamestickservices.net/check.php.rst
index c28e3f9e7af96a67dcce5f0de9abcad7564df236..227a407db7c7b120234cebabbf198979b6470af0 100644 (file)
--- a/api/update.gamestickservices.net/check.php.rst
+++ b/api/update.gamestickservices.net/check.php.rst
@@ -94,3 +94,14 @@ After download and chunk combination, the file is verified by standard Android
 mechanism ``android.os.RecoverySystem.verifyPackage()``.
 
 Information about the new firmware is written to ``/data/GameStickCache/update.info``.
+
+
+Chunks
+------
+Generating chunk files:
+
+1. The firmware update file must be split into files of 102400 bytes.
+2. Each part must be XORed with 91 (hex ``5b``, binary ``1011011``).
+3. The binary SHA1 sum of the XORed part file must pre prepended before the data
+
+Having a single chunk file only should work, too.