Difference between revisions of "CM11A"

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''For setup information see [[CM11]]
 
''For setup information see [[CM11]]
 
== Description ==
 
== Description ==
CM11A is a device that uses [http://hypermetrics.com/rubyhacker/x10proto.html X10] protocol to control lights (and may be other stuff) around the house by injecting data into powerline.
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CM11A is a device that uses the[http://hypermetrics.com/rubyhacker/x10proto.html X10] protocol to control lights (and maybe other stuff) around the house by transmitting data over powerlines.
  
Each X10 device has an address formed as ''housecode''[A..P]+''unitcode''[1..16]. As powerlines are usually shared between near houses/apartments it's a good idea to choose other housecode than your neighbor, or purchase and properly install a filter.
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Each X10 device has an address formed as ''housecode''[A..P]+''unitcode''[1..16]. As powerlines are often shared by neighboring houses and apartments, so it's a good idea to choose a housecode different from your neighbor's. Otherwise, purchase and properly install a filter.
  
To control those devices you need a small box which is connected to computer (this one is CM11A), with it you can send commands to the devices.
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To control those devices you will need a small interface box which is connected to computer (the CM11A)). With it you can send commands from the computer to the devices.
  
The command usually consist of few bytes (command itself and unit to control) and an exchange of checksums needed because the line may be noisy and commands weren't received correctly. In this case the retransmission is required by protocol.
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The command usually consist of a few bytes (the command itself and the address of the unit to control). An exchange of checksums is needed because the lines are often noisy and commands may not be received correctly. In noisy conditions, retransmission is required by protocol.
  
There are several commands the LinuxMCE's CM11A implements:
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There are several commands that LinuxMCE's CM11A wrapper implements:
 
* '''CMD_Generic_On''' will send x10 ON
 
* '''CMD_Generic_On''' will send x10 ON
 
* '''CMD_Generic_Off''' will send x10 OFF
 
* '''CMD_Generic_Off''' will send x10 OFF
* '''CMD_Set_Level''' depending on the existing level versus requested level will send DIM or BRIGHT
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* '''CMD_Set_Level''' depending on the existing level. The requested levels will send DIM or BRIGHT.
  
Some devices may send commands to CM11A device (mostly motion detectors or some other bidirectional devices). We don't have any in the office so even if the code exists, it wasn't tested properly, but it should send SensorTripped event.
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Some devices may send commands to CM11A device (mostly motion detectors or some other bidirectional devices). We don't have any in our office, so even if the code exists, we were not able to test it properly. It should be able to send a SensorTripped event.
  
 
== Implementation notes ==
 
== Implementation notes ==

Revision as of 04:30, 29 May 2008

For setup information see CM11

Description

CM11A is a device that uses theX10 protocol to control lights (and maybe other stuff) around the house by transmitting data over powerlines.

Each X10 device has an address formed as housecode[A..P]+unitcode[1..16]. As powerlines are often shared by neighboring houses and apartments, so it's a good idea to choose a housecode different from your neighbor's. Otherwise, purchase and properly install a filter.

To control those devices you will need a small interface box which is connected to computer (the CM11A)). With it you can send commands from the computer to the devices.

The command usually consist of a few bytes (the command itself and the address of the unit to control). An exchange of checksums is needed because the lines are often noisy and commands may not be received correctly. In noisy conditions, retransmission is required by protocol.

There are several commands that LinuxMCE's CM11A wrapper implements:

  • CMD_Generic_On will send x10 ON
  • CMD_Generic_Off will send x10 OFF
  • CMD_Set_Level depending on the existing level. The requested levels will send DIM or BRIGHT.

Some devices may send commands to CM11A device (mostly motion detectors or some other bidirectional devices). We don't have any in our office, so even if the code exists, we were not able to test it properly. It should be able to send a SensorTripped event.

Implementation notes

  • CM11A is responsible for getting commands from LinuxMCE and transform them in X10 commands
  • DevicePoll will do all the communication with device (sending commands, checking checksum, etc) and also will treat any InterfacePool requests coming from bidirectional devices.
  • Message will transform unit code from for example 'A9' into internal X10 code '67'. Don't ask why, that translation is required by protocol.