Reverse engineering ELRO DB280 Doorbel
The ELRO DB280 is a doorbel system with a wireless remote. The system has a fixed code, although it can be changed quite easily by changing some "solder bridges"
We analyzed the wireless signal with an Logic analyzer and a 433 receiver.
The jumpers are set:
After analysing the pulses with the logic analyzer we do see the following
If we invert the set jumpers and we the code 1 character we see the following:
0 1 1 1 1 0 1 1 0001010101000101010101010
We can conclude:
- Every pulse uses a 0 in front
- The code is inverted (or it's default up unless it's brought to the ground)
- There is a trailer: "010101010"