PC-Based Smart Home Controllers

Today I’m going to discuss a range of X10 compatible PC controllers that the budding smart home enthusiast could take advantage of. These devices allow for the control of appliances by set times or through the sending of immediate commands. Before choosing a controller it is necessary to weigh up the limitations of each, with special consideration given to the reliability, as well as, how easy a custom application could communicate with… the device, should you wish to make one.


The most widely used controller is the CM12U. It connects to real time the PC via serial link and when batteries are placed into the device it is capable of storing user defined settings, for example if the home owner wanted the lights to turn on at 6pm, this can easily be accomplished by the CM12U even when the computer is turned off. A major limitation surrounding the CM12U is the fact that it uses a serial port for communication, which most PC’s do not support these days.

When I tried out a CM12U I purchased a serial to USB (Universal Serial Bus) adapter with the hope that it could work on my USB only laptop but to no avail. I assumed that this was due to the fact the CM12U has been around for a long time without much advancement, therefore compatibility even with a supposed adapter has not truly been considered.


The CM15A is essentially an evolution of the CM12U and makes use of a USB connection, rather than serial. This eliminates the problem of only being able to use the device on certain computer systems. It also consists of a wireless transceiver, thus providing a more elaborate means of communication. On first glance it might seem obvious to choose this device over the CM12U; however the device is known to be unreliable, not just with the additional wireless capabilities but also with the sending and receiving of signals over the household wiring, which the CM12U actually does rather well.

SmartHome PowerLinc Controller 1132CU

The PowerLinc controller developed by SmartHome connects to a PC via USB, just like the CM15A and is also capable of initiating pre-defined settings when the computer is switched off just like the previously mentioned devices. The built in backup battery has a 10 year lifespan, a good advantage over the other two components. If you wanted to create your own custom application the PowerLinc is not a good one to choose because it is a lot harder to program than the other two devices, down to the fact there isn’t much in the way of support for the development of your own application using this device.