I have for some time no wanted to write text to the E46 (low) cluster to advertise speedcameras (speedlimit and distance) using for example "GATSOHunter" and "RoadRunner"
My thought was to have the arrows flashing to draw your attention to the cluster, and then present the current speedlimit followed by the distance to the speedcamera (GATSO).
After some digging through the web I have understood that writing to the E46 (low) cluster is not possible... WRONG!!!
Now I have finally succeeded to do just that...
The clue is that it MIGHT not be possible to DIRECTLY write text to the alphanumeric display, but use it's pre-defined messages kind of...
There are afaik 3 different types of messages that can be displayed:
-Distances in meters or feet
-Speeds in km/h or mph
-Temperature in degrees Celsius or Farenheit
Maby it's possible to write "plain" text as well, this I don't know at the moment.
Today I logged the following _DISTANCE_ codes and tested to write them back to the cluster with success:
_HEX codes WITH checksum attached!_
7F 05 80 44 29 30 A7 <--- 300m
7F 05 80 44 29 25 B2 <--- 250m
...
7F 05 80 44 29 10 87 <--- 100m
7F 05 80 44 21 90 0F <--- 90m
7F 05 80 44 21 80 1F <--- 80m
7F 05 80 44 21 70 EF <--- 70m
7F 05 80 44 21 60 FF <--- 60m
7F 05 80 44 21 50 CF <--- 50m
...
7F 05 80 44 21 10 8F <--- 10m
7F 05 80 44 21 00 9F <--- 0m
7F 05 80 44 20 00 9E <--- CLEAR DISPLAY? (this was the last code logged from the GPS -> IKE
Here the GPS (7F) is the source and the IKE (80) is destination.
The first DATA byte, (the fourth byte in the string) seem to be the code for "distance display". That is the "m" is displayed after the data in the display.
The second DATA byte, (the fifth byte in the string) it is used to distinguish between 100's and 10's.
The third DATA byte, (the sixth byte in the string) is the actual distance data.
I have logged codes for speedlimits as well, but I have lost that log. I'm pretty sure that the format is very similar, but with another hexcode for the FIRST databyte to put the display in "speedmode" for example.
Will test "speeddata" tomorrow...
Kind regards
Marc in Norway