The ISY-26 system controller is bilingual — it knows how to send and receive both Insteon and X-10 control signals. This means one may use existing X-10 controls as part of a mixed X-10/Insteon system, and one may also use X-10 devices that are not available in Insteon form at the time of writing.

I have some old X-10 remote controls with enought buttons to suit my needs (big house, lots of controls) and when I began planning my Insteon installation, I decided the existing Insteon remote controls (example: 2440BK) didn't have enough buttons. This temporarily halted my Insteon planning until I realized the ISY-26 could translate X-10 signals and produce suitable Insteon commands (and I finally acquired an Insteon remote, which is rather good).

Here is an example. In my old X-10 system, I would use an UR19A remote to issue a command to house code 'H', unit code '1' to turn on my external lights. Then an RR501 wireless receiver would pick up the remote control's radio transmission and produce appropriate X-10 format, 120KHz power line signals.

In the new system, all the above events still take place, but in a third step, the ISY-26 runs this program to process the X-10 signal and issue an Insteon command:

If
        X10 'H1/On (3)' is Received
Then
        Set Scene 'External/Foyer' On
Else
   ...

Remember from the previous section that we need to be very explicit with a computer and cannot assume anything, because although computers possess plenty of logic, they don't possess any common sense. Consequently, we need to have this program also:

If
        X10 'H1/Off (11)' is Received
Then
        Set Scene 'External/Foyer' Off
Else
   ...

Here is an example that detects a signal from a motion sensor and decides whether it's appropriate to turn on the exterior lights. I have programmed my X-10 motion sensor to emit house code H, unit code 15 when it senses motion:

If
        X10 'H15/On (3)' is Received
    And From    Sunset  + 10 minutes
        To      Sunrise - 10 minutes (next day)
Then
        Set Scene 'External/Foyer' On
        Wait  2 minutes 
        Set Scene 'External/Foyer' Off
Else
    ...

This X-10 control translation can work in both directions. Let's say we have a mixture of Insteon and X-10 controls, and we want to be able to control them together. In this hypothetical example, we have a room with one Insteon and one X-10 control and we want both of them to turn on when the Insteon control is activated:

If
        Status  'Radio Room 1' is On
Then
        Send X10 'H5/On (3)'
Else
   ...

I think the reader will appreciate that this X-10 translation activity is temporary, until there is a complete set of Insteon controls inclding remotes with lots of buttons, motion and other kinds of sensors, that is, everything now available for X-10 systems.