The CM15 is X10's update to the CM11.

The serial connection was replaced with a USB connection so no USB Serial adaptor is required. Unfortunately since they did not implement a device serial number to tell multiple instances apart, only 1 CM15 can be connected to XTension at a time.

XTension supports the CM15 for receiving X10 wireless commands

XTension supports the CM15 for receiving X10 security commands.

XTension supports the CM15 for transmitting X10 wireless and Ninja camera mount remote control. (NOTE: transmitting X10 wireless commands requires at least build 775 which is currently available on the beta page)

CM15 support is included in XTension and does not require any plugins or additional software licenses.

Like the CM11a the CM15 advertises the ability to download a subset of commands to the interface and have it function as a simple timer without a computer attached. XTension does not support downloading to the interface and must remain running in order to support it's full feature set. You should not put batteries in your CM15 when in use with Xtension.

the CM15 in the picture has custom added coax connections for receiving and transmitting antennas in an attempt to increase it's range. These are not part of the shipping product but can be added after the fact by an enterprising user with a soldering iron and no respect for their warranty.

Any wireless commands received on the “A” house code will be automatically forwarded to the powerline. Xtension will receive them as well but it cannot stop them being echoed onto the powerline.

The CM15 is unable to send an X10 signal while it is still receiving a wireless signal. XTension attempts to wait for the wireless signal to finish before sending any powerline commands that it might generate but this can cause timing issues. For example, if you have a wireless remote that sends an ON for a lamp, the ON wont be able to go out until you stop holding the button down.

Wireless reception and transmission range is limited by the included antennas, however if you're willing to take a soldering iron to the inside of the case it is possible to add a coax connection for a better antenna.