adding all checksum algorithm informations

Phil242 · Apr 12, 2022 · 3f16f43 · 3f16f43
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diff --git a/Protocol b/Protocol
@@ -1,5 +1,18 @@
 This the UDP protocol of Besen WB with APP
 
+
+**************************************************************************************************
+Packet checksum
+**************************************************************************************************
+
+Each UDP packets have a checksum at the end, stored before the 2 last constant bytes.
+The algorithm is quite simple (and scary!):     
+You just need to add each byte of the packet, byte per byte, from the first 0601… to the last byte before the checksum.        
+Each round you need to do a modulus 0X10000 to be sure the sum didn’t go behind 16 bits. And that’s it!
+See the C code example in the folder Checksum.
+Checksum is stored in Big Endian.
+
+
 **************************************************************************************************
 Command: Stop Charging
 **************************************************************************************************

diff --git a/README.md b/README.md
@@ -16,11 +16,11 @@ See for example https://community.home-assistant.io/t/wallbox-pulsar-plus-integr
 - Understanding how the phone and the wallbox exchange data    
 - Replay successfully a past charging command, with an old timestamp without modifying it        
 - Stop charging command has been reversed engineered  
-- Analysed SAE J1772 max control pilot usage for max current.
+- CRC algorithm reversed, understood and implemented
+- Analysed SAE J1772 max control pilot usage for max current
 
 #### In Progress:
 - Start charging command reserve on the go      
-- CRC algorithm reversed and understood, but needs more checks      
 - Reversing the only available firmware for ARM board (unknown model)       
 
 #### TODO: