Decoding of tag data

This test is done with a newly started tag. By chance I noticed that if you read the first four bytes of the data and AND it with 0xFFF you will get a graph that is rather near to the blood sugar data from the reader device. You can see it on the images: (Black line = Reader Data, Green line = Data that I calculated from tag data)

As you can also see, the data is somewhen passing away from the calculated green curve. I guess that with time, the tag builds up some knowledge about better calculating the real blood glucose value.

If I used my method for a tag that runs for 10 days, the green line is just garbish. For the generated images I used the formula: ((First two bytes) & 0xFFF / 6) - 37