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by George McKechnie

For an introduction to programmable remote controls, see Very Smart Remote Control Systems. Here, we continue the topic by exploring advanced features like bi-directional and touchscreen remotes, RS-232 control, the use of tablets and smartphones as remotes, as well as some important technical issues.

Bi-directional Remotes

Most universal remote control systems (and virtually all remotes shipped with components) are uni-directional. They send command codes to their dedicated electronics devices, one-way only, with no acknowledgement that the command was received. You know they have succeeded when the component you are trying to control responds in the way you intended.  If not, try again.

Most advanced remotes offer bi-directional operation.  In addition to sending commands, they can receive signals—from one or many components—so they can confirm that the command (or commands) was received.  More importantly, they can receive a wide range of other data and display it—including such meta-data as the playlist on a smart phone, or the name of the song you’re listening to.

Some of these devices can even handle broadband communication; you can use them to surf the internet or display streamed video. Because the additional features often involve the display of video data, these remotes are typically large, two-handed units with color touchscreens, and come with docking stations and rechargeable batteries.

RS-232 Control

As described in Very Smart Remote Control Systems, IR data transmission can be problematic, since it relies on a line-of sight light pathway and a steady aim.  Even RF control can be less than perfect, as it ultimately relies on IR flashers to deliver the data to the IR sensor that is located on the front panel of most consumer electronic products. These flashers are manufactured with a sticky surface, so that they can be attached directly over the IR sensor.  With time (or spring cleaning), these flashers can slide away from the sensor or even fall off the front panel of the component, losing the IR “connection.”  To restore communication, they must be re-positioned in the exact right place or they won’t work properly.  To keep them in place after they’ve fallen off a few times, it’s sometimes necessary to resort to superglue.

An alternative transmission method, borrowed from the computer industry, avoids this problem. Named RS-232, this communications protocol allows components to be hard-wired to the remote control system (or to the RF receiver, in the case of wireless remote controls), thus avoiding the problems associated with IR and RF technologies.  Because RS-232 is the most reliable communications method, many brands of premium-grade components (and the upper end of some consumer-grade lines) support RS-232 communication.  A special port for this purpose is located on the back panel of the component, and connects to electronics inside that implement this feature.  Most advanced remote control systems support this system, along with RF and IR control.

A few caveats regarding RS-232: first, this feature is typically not available in entry level consumer grade products, or on Cable or Sat boxes.  Second, RS-232-enabled control systems are more expensive than those limited to IR/RF communication.  And third, because there is no uniform industry-wide wiring standard for RS-232, cables must be custom-fabricated for the actual components being controlled, increasing labor costs slightly.

Keypads vs Touchscreens

Standard-issue remotes supplied with electronic components typically use a handful of pre-labeled buttons arranged as a keypad to control the dedicated component.  Universal remotes vary in design, depending on the intended application and price.

Entry level universal remote models will typically have a large keypad area, along with a small greyscale LED screen which can be programmed to define the functions of up to 10 buttons positioned to the left and right of the screen.  Home page on the display is usually programmed to offer the user a choice of sources—such as Cable TV, Blu-ray, CD, etc.  Additional “pages” can be programmed to label additional functions (like the names of favorite TV stations or special buttons to navigate a built-in DVR).  These are displayed on the screen as needed, depending on the macros that are programmed into the system. Each page will display the labels for the functions available when that page is shown.  A macro is selected by clicking the button next to the label on the screen.  Further pages will provide other macro choices.

In a typical application, the home page displays the choice of source components available: Satellite, Blu-ray, CD, DVR, internet streaming, etc.  If the user selects the Satellite button, the macro programmed into the remote will send out a series of commands to turn on all the components needed to watch a show via Satellite, and to adjust the needed settings on the components so that the satellite sends an image to the TV and sound to the speakers.  Then, by selecting favorites, the user’s preferred TV station names (ABC, CBS, PBS, ESPN, etc.) appear next to the buttons.  Perhaps several screens of favorites will be needed, depending on the breadth of viewing of the family.

If satellite music is important to the user, an extra page might be programmed to appear first, with WATCH and LISTEN buttons to choose from.  Once the Watch/Listen choice is made, another favorites page will appear, offering either music favorites or TV favorites from which to select.  If Listen is chosen, the macro will turn on all of the usual components.  Then, after you have made your music station selection, the remote may be programmed to turn the TV off (since you just want to listen to music, and want to save energy).

Mid-market universal remote models may sport small color LED screens, again with buttons along the sides to select from among the functions defined on-screen.  These programmable remotes do a great job of controlling home theaters, and are justifiably very popular.  Some models even have enough computing power (and display area) to control other systems, too: distributed audio, simple alarm systems, and limited lighting control.

Larger, two-handed models typically offer color touchscreens, with or without associated keyboard buttons.  Screen size can range up to 16 inches diagonal or more.  A full Graphical User Interface (GUI) allows the screen appearance to be fully customizable, so it can be adapted to almost any application.

Perhaps the user simply wants a large NFL Channel logo to dominate the home page—a hard-to-miss target!  Or, if security is of paramount concern, the screen might show a floor plan of the home, with red and green lights indicating which doors and windows are locked.  Another page might show the floor plan displaying the on/off status of all the lighting control devices in the home.

7_Advanced Remote Controls-02Dedicated Remotes vs Tablets

With smartphones and tablets increasingly popular these days—with apps available that can perform simple smart home tasks—the question arises: will these devices replace dedicated remote controls?  The answer is probably not very soon, for a number of reasons.  First, unless it is dedicated solely to home integration control, a typical phone or tablet may have too many competing apps and screens on the display or in drill-down menus to allow easy control of all the smart home integration systems in the home. The number of clicks or touches needed to get from the home screen to change a TV channel may defeat the whole purpose of macros, which is to accomplish a complex operation simply and almost instantaneously with a single stroke of a the keypad or touchscreen.

Second, although some smartphone models can multi-task, most cannot easily be used to simultaneously answer a call or surf the net plus turn on or navigate through a home theater system—or activate the security system, or check a surveillance camera.  In time this may change—probably will—but not yet.  For now, many makers of dedicated touchscreen remotes offer table and smartphone apps, which allow these devices to be used as a backup to a dedicated remote.

Third, most current smart phones have a usable battery charge of about 8 hours or less, depending on the extent of daily use.  For most users, this means recharging every night—just when you want to settle down for some good entertainment. Entry-level universal remotes use batteries that last 4-6 months before replacing, depending on the model and use pattern.  Upscale models, with rechargeable batteries and a recharger built into a docking station, may last a week or two between charges when used as a regular remote—less if used for surfing the internet or streaming content.  But since they are intended to sit in their recharging dock when not in use, this seldom presents a problem.

Fourth, and probably most important, effortless control of home integration systems (especially home theaters) requires the creation of macros which typically contain workarounds—special programming routines that might rely on custom-timed and sequenced redundancies or other tricks—which have been programmed by specialists who know how to tame thousands of products from hundreds of manufacturers (sometimes including those from different eras) so they can be pulled together into smooth-working systems.

This challenge is well beyond the app store business model, where economies of scale require a standardized cookie cutter approach.  And because programming dedicated remotes requires extensive knowledge of audio/video product idiosyncrasies, it is not something that the typical IT professional is able to tackle.

Adaptive Solutions

Visually-impaired consumers and those with other special needs can sometimes be assisted greatly by remote controls that are custom programmed to help compensate for their particular disabilities.  Often, this is done in combination with specific adaptive home integrations strategies, as described elsewhere.  Sometimes the remote itself is a key part of the solution.  See Aging in-PlaceAn Electronic Safety Net for Elders

Consider, for example, someone with a significant visual impairment.   An oversized TV screen viewed from close up may markedly improve their viewing experience, by helping them to see key facial cues that let them “read” emotions—whether watching drama, a comedy show, or a spectacular moment in a football game.  But how to help them change stations when others are not at home?   Even a normal universal remote may be beyond the limits of their limited visual acuity.  Solution:  An oversized color touchscreen remote programmed to compensate for their limited ability. Here’s how.

Say, for example, the person mostly watches shows on four favorite TV stations.  To help the person navigate between them, a simple Graphical User Interface (GUI) could be created by dividing the screen into four quadrants, each with a different color.  Each quadrant is set up as a mini-macro leading to a different favorite station.  Touching any one of the quadrants turns on all the system components, selects Satellite TV, then tunes to the particular station corresponding to the color chosen.  All the person must do is to learn the color associated with each favorite TV station.  A fifth, small macro button is programmed into the corner of the screen.  It jumps to a standard home page, converting the unit into an ordinary universal remote, programmed to the needs of the family.


Here are some behind-the-scene issues that can interfere with seamless performance of a remote control system.  They may seem esoteric.  But if they get in your way, you’ll be glad to know about them.

Code Deficiencies

Not all component manufacturers use control code systems that are up to current standards with regard to smart home applications.   One often-encountered challenge when programming a universal remote to a home theater is the seemingly trivial matter of reliably turning a component on and off.  Until recently, many manufacturers controlled the component on/off with a single toggle code.  Some still do.

Here’s how it works.  The control codes are set up so that when you press the on/off button once, the component (your TV for example) turns on.  Press it a second time, and the TV turns off.  This sounds fool-proof, but it’s not, especially if there is more than one component in your system with toggle on/off codes, and you are trying to control them with a macro-enabled remote using IR communication.

Let’s say you have four components in your home theater system: TV, Blu-ray, Surround Receiver, and Satellite Box. They’re all within line of sight, and you have a universal remote (programmed with macros) that sends out all the codes via IR.  To get perfect communication, you must point the remote steadily at the components, and hold it long enough so that each one gets the codes it needs for the macro operation to be fully successful.  [This is much less of a problem with RF controlled systems, since the remote doesn’t have to be pointed at a sensor to reliably communicate the full macro code string to all the components.]

If your hand is unsteady, if you are distracted by a dog barking and turn to look, or if you suddenly need to scratch your back with the remote, one or more of the components will not receive all the codes built into the macro, and you won’t get where you want to go. Maybe only two of the components received the on/off code, and the Surround Receiver is still off.  So you try it again, this time making sure to hold the remote steady, as you count mentally to 5.  This time, the Surround Receiver does get the code—you hear the reassuring click as it turns on.  But the components that you previously turned on a few seconds ago (with the incomplete macro string) now turn off, because the manufacturer’s on/off codes are set up as on-off toggles.  And instead of easy navigating (as promised by the macro feature), you get frustration.

The solution: use only components with what are called discreet on/off codes.  Instead of employing the old fashioned single code (which toggles back and forth between on and off), new school components are controlled by separate codes for “on” and “off”.  The “on” code means: turn the component on, and if it is already on, leave it on.  And the “off” code means: turn it off, regardless of its current state.  This solution is so simple you’d think all manufacturers would have adopted it.  But they haven’t. This problem can cause so much frustration that most A/V specialty dealers sell only components with discreet on/off codes, and are reluctant to program remotes for components that toggle between off and on.

RF Interference

Transmitters built into RF-enabled remote control systems typically have a range of about 30-60 feet or more, depending on the make and model, the presence of metal construction features of the building, and the charge on the batteries.  Because these RF devices can transmit well beyond the line of sight, a problem of interference can arise—two or more universal remotes (in a home or apartment complex) operating on the same frequency, unintentionally controlling more than one system.  In such a situation, your neighbor’s remote could control your equipment, or the bedroom remote could control the family room system.

To solve this problem, many RF-enabled universal remotes provide a choice of frequencies over which to operate.  This way, if you have multiple remotes in your home (or if a close neighbor happens to use a remote system which operates on the same frequency as yours), yours can be set to a different frequency.  Then you won’t have to worry about someone changing your channel during the winning play of the Super Bowl!

One final point about RF controls is worth mentioning.  Manufacturers of TV lift cabinets, drop-down TV and projector devices, and other motorized A/V products typically ship them with a dedicated RF—not IR—control.  Because these devices are set to a proprietary frequency chosen by the manufacturer, they cannot be controlled directly by RF-enabled universal remotes.  But most of these manufacturers do offer accessories that convert their systems to IR or RS-232 control, allowing them to be integrated successfully into home theaters or other systems.

Regardless of these minor hurdles, in the hands of experts universal remote controls can virtually always be programmed to achieve this goal: to integrate any combination of products—from the tens of thousands of components made by hundreds of brands made over a decade or more— and control them easily and flawlessly.   Over the years, experienced programmers have created and shared thousands of “work-arounds,” safety-net redundancies, and rescue solutions to mitigate a wide range of challenges that inevitably arise when such varied products are integrated into a multi-system smart home.  This is the untold story behind successful home integration.