Classic Computer Magazine Archive ANTIC VOL. 7, NO. 4 / AUGUST 1988

Power Manager X-10

Atari home controller connection

By Charles Cherry

One interesting application that was never previously available for any Atari is computer control of the X-10 PowerHouse home controller system. X-10 provides its own software for the Apple II, Commodore 64 and IBM, but left out the Atari. This unfortunate lack has now been corrected by Terrific Corp., whose PowerManager provides all the features available on other computers.


For those Atarians not familiar with the X-10 home control system, here's a brief overview:

A master controller turns lights and appliances (or anything else with an electric switch) on and off. A separate slave module is used for each item to be controlled, whether it's a lamp, appliance, wall socket, wall switch or thermostat. The lamp and wall switch modules also provide 16 levels of dimming.

The signals that control the slave modules travel through the normal house wiring. That's the real magic of the X-10 system – no additional wiring is needed. Just plug in the modules and you have remote control. I once worked with a small traveling theater company which used the X-10 system for stage lighting. We just plugged everything into the wall and were ready to go. No need to run cables everywhere. It was great.

X-10 PowerHouse hardware is reasonably priced and widely available from all kinds of stores that sell household electronic supplies. The controllers and modules are sometimes on sale for next to nothing. Even if you pay full price, the system's "power without the price" is an unbeatable value. The X-10 could be called the Atari of remote control systems.

Several different X-10 controllers are made, from simple manual ones to complex timers, wireless transmitters and even a telephone operated controller. The controller we're concerned with is the model CP290, PowerHouse RS-232 Computer Interface. With this controller – and the proper software and cable – your computer controls the PowerHouse system. The PowerManager provides the proper software and a cable that connects your Atari to the CP290.


The PowerManager cable plugs into joystick port 2. This saves you the cost of an RS-232 interface (such as an Atari 850 or a P:R: Connection). But it means you must be careful with the cable. Don't leave it plugged in when you run other software. Likewise, don't leave things like your PaperClip key plugged in when you run PowerManager.

The software is very similar to what's available for the other computers, except that X-10 software uses graphics – pictures of rooms into which you put icons of your lamps and appliances. PowerManager, however, identifies the devices numerically. Personally, I think PowerManager got it right. The X-10 pictures are cute, but they don't look like my house and there's no logical way to indicate devices that aren't in a room, like the porch lamp, the garage light or the automatic spririkler system.

The X-10 interface is limited to 16 devices. Eight can be manually controlled by switches on the interface and all 16 can be controlled by the computer. Actually, many more than 16 can be controlled by the computer. It seems that since the signals travel on the house wiring, there's a chance that you will also control your neighbor's X-10 system, if you are connected to the same local transformer (those big boxes on top of utility poles, usually serving about half a block).

To prevent this, each device can be set for a "house code." You and your neighbors decide who gets what code: "You're A, I'm B and the Murdocks are C." There are 16 house codes. If more families on your block get X-l0 systems, you're out of luck. However, it's unlikely that many of your neighbors are using the PowerHouse system. This means all those house codes are available for you – 16 house codes with 16 devices each, adds up to 256 devices. Now that's a respectable remote control system.

You can use the PowerManager software in two different ways. First, you could control your house directly from the keyboard or joystick. More likely, you will choose to program the interface to run from its internal timer. You can schedule as many as 128 different events. Each event can control one, several, or all of the 16 devices in one house code. You schedule each event for a specific time and have it automatically repeat on one or more days of the week. Or you can program events to occur on each scheduled day within an hour of the set time. This makes your home looked more lived-in while you are on vacation.

When your schedule is complete, you can save it to disk. You can build a library of schedules for various situations, such as summer, winter, vacations, etc. Once you select a schedule and upload it to the X-10 interface, the interface runs on its own. So you can use your computer for other things. The interface even has a 10-hour battery backup in case of power failure.


I found the logic structure of the menus inconvenient. You can only set the time and the default house code upon first booting. The arrow keys and [RETURN) are inconsistent and you cannot exit from a menu when you want to.

Another problem is the clock. It changes from a.m. to p.m. and back at 1 o'clock, not 12, so 12:30 in the afternoon must be entered as 12:30 AM, and 12:30 at night must be entered as 12:30 PM.

Also, I kept getting the following cryptic message: "* Error: Interface was powered down. *" I couldn't understand this, since the interface was plugged in and seemed to be working fine. In fact, everything worked just as it should have. Later when I read the X-10 programming guide, I realized the PowerManager was saying that the memory of the interface had been erased – it had been unplugged and "forgot" its previous programming. I don't think that qualifies as an error.


The PowerMaster X-10 was designed for home control and it works well there. I particularly enjoy waking to the glorious sound of my monster stereo instead of my tinny little clock radio. The system makes coffee and toast in the morning and it warms up the electric blanket before bedtime. It has eliminated the need for a $75 programmable set-back thermostat, and it remembers to turn on the porch light before my wife gets home and turn it off when we go to bed. When I get some relays and solenoids, I'll build an automatic cat feeder.

Home control is sort of a game. It's fun to plan your 2lst-century house. This programmable system can replace many expensive dedicated systems to control sprinklers, solar heating, fans, security systems, etc. And it's all done with little or no rewiring. However, the X-10 is not limited to the home. (Remember, we used it for a theater.)


Any application requiring remote control is a candidate for the X-10. And if that remote control needs to be programmed, an Atari with the PowerManager is a cost-effective solution. The individual modules are limited to switching 15 amps or dimming 300 watts, but they can drive relays to control larger loads like floodlights and electric signs.

Of course, the system is a natural for science fair projects and other experimental control systems. You should be warned, however, that in the scheduled mode, it's only accurate to within one minute. In the direct mode, you can get about 10-second accuracy, but that brings up another problem. There's no information on using this system in your own programming. The X-10 software for other computers includes a utility program to help you write BASIC applications. We could use the same for the PowerManger.

Writing custom software using the Atari's joystick and paddle inputs can create a simple data acquisition and process control system. A moisture sensor can trigger a pump, a phototransistor can turn off the lights, the vast array of security detectors (motion sensors, magnetic field detectors, infrared sensors) can be used to set off the appropriate responses.

(Antic would be interested in publishing software/hardware articles about interesting original X-10 PowerManager uses. – ANTIC ED)

Terrific Corp.
17 St. Mary's Court
Brookline, MA 02146
(617) 232-2317
$44.95, 48K disk. (Includes cable)

X-10 (USA) Inc.
185A Legrand Avenue
Northvale, NJ 07647
(800) 526-0027
(201) 784-9700–New Jersey