Reverse engineering ELRO HA51 wireless: Difference between revisions

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We hooked up a logic analyzer on the 433 receiver board to "snif" the datastreams:<br>
We hooked up a logic analyzer on the 433 receiver board to "snif" the datastreams:<br>
We opened the remote to change the dipswitches:
We opened the remote to change the dipswitches:<br>
[[File:Elro_HA51_remoteinside.jpg|200px]][[File:Elro_HA51_remoteinsidedips.jpg|200px]]<br>
[[File:Elro_HA51_remoteinside.jpg|200px]][[File:Elro_HA51_remoteinsidedips.jpg|200px]]<br>


=Results=
After sniffing a few times this the result:<br>
After sniffing a few times this the result:<br>
"Put alarm off" with all dips off:<br>
"Put alarm off" with all dips off:<br>
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[[File:Elro_HA51_433_allon_alarmoff.png]]<br>
[[File:Elro_HA51_433_allon_alarmoff.png]]<br>
As you can see, the first pulse is always short, the next 8 pulses is the code of the system, dip "off" is a small pulse, a wide pulse is dip "on".
As you can see, the first pulse is always short, the next 8 pulses is the code of the system, dip "off" is a small pulse, a wide pulse is dip "on".
Also we have seen the last 4 pulses are used to control the system:
Wide=1
Small=0
System off: 1100
System on: 1110
System Delayed on: 1011
Panic button: 0011
Other codes will be added after analysing (PIR, door detection etc)

Revision as of 19:37, 30 July 2012

What is it

It's a alarm system, used with wireless accessories. We have a central and a remote control:

Setup

We opened the device, no internal alarm trigger's where used. The system contains 2 board:

  • Logic board
  • 433 receiver

We hooked up a logic analyzer on the 433 receiver board to "snif" the datastreams:
We opened the remote to change the dipswitches:

Results

After sniffing a few times this the result:
"Put alarm off" with all dips off:

"Put alarm off" with all dips on:

As you can see, the first pulse is always short, the next 8 pulses is the code of the system, dip "off" is a small pulse, a wide pulse is dip "on".

Also we have seen the last 4 pulses are used to control the system: Wide=1 Small=0

System off: 1100 System on: 1110 System Delayed on: 1011 Panic button: 0011 Other codes will be added after analysing (PIR, door detection etc)