Update readme.txt

Re-phrased, added more infos

tools/readme.txt

@@ -1 +1,39 @@
+Settings file (xslx):
+
+Thanks to user ClearY /ClearEyetem) from the Haustechnikdialog forum for providing this:
+https://www.haustechnikdialog.de/Forum/t/226142/Neue-Fernwaermeanlage-How-to-start
+The file helps you to note all settings of your Trovis. 
+
+
+Sniffers / .py files:
+
 Use these tools with caution - they were made quick&dirty and are highly experimental.
+The tools check one by one if a register/coil is readable.
+If yes, the value is displayed - if no, an error is shown.
+At the end, all found blocks are shown, and a 'quick read-out' by using validated blocks
+instead of single registers/coils is done.
+
+The tools require that you can communicate with your Trovis, so a stable interface is a MUST.
+
+The following points need to be validated / changed in case of need:
+- Interface: Default in code is /dev/ttytrovis, may need to be changed to /dev/trovis or such
+- Unit no.: Default in code is 247, may need to be changed as set in trovis menu
+
+A 'block' the sniffers shall check for readable registers/coils should not exceed 120
+(recommended: 100 to keep it easy and to be on safe side).
+
+Pretty much on top of the code, you can add search blocks by adding new lines as follows
+(add as many lines/search blocks as you like):
+suchbereiche.append([0,99])          # Check first block of 100 registers (0-99)
+suchbereiche.append([100,199])       # Check second block of 100 registers (100-199)
+suchbereiche.append([765,798])       # Check third block of 100 registers (765-798)
+
+Usage:
+- check/validate above points
+- amend registers as needed to source code
+- run a shell:
+> cd /usr/local/smarthome/plugins/trovis_557x/tools  # or wherever shNG resides
+> python3 register_sniffer.py
+> python3 coils_sniffer.py
+
+Note: When seaching for many registers/coils, it may take hours to finish!