Why not Bluetooth for TV remotes? [Caavo]

There is a review here:
of a new universal remote control called Caavo. This system goes to extremes to control video devices: it has a smart HDMI switch that connects to your TV and all types of streaming and media playing devices. The switch actually decodes the video and “looks at the screen” to figure out what state your Apple TV or Xbox One is in, and then emits infrared signals (as well as Ethernet and HDMI-CEC control signals) to control the devices. Their goal seems to be providing a single interface to select content from any source.

This has to be a fairly powerful computer to process and interpret video. The manufacturer must have a huge lab with One Each Of Everything and a team of software developers watching for firmware upgrades and pushing out new control profiles to the devices. Caavo is making a heroic effort to do something that the manufacturers have made hard: automatically control AV devices. Good for them but there ought to be a better way.

TV remote technology is stuck in the 1980s. There have been four generations of TV remotes. Gen 1 (1950s Space Command) had a light sensor at each corner of the screen. The remote control was a flashlight.

Gen 2 (1960s) was acoustic with a microphone in the TV, a tuned circuit for each function, and a set of mechanical chimes in the remote. The tuner knob on the TV actually moved when you operated the remote. DING – kerchunk!

Gen 3 (1970s) was ultrasonic with a piezoelectric transmitter and a battery in the remote. The TV still had a set of tuned circuits. There was one of these in my house as a kid, and jingling a large handful of quarters would reliably turn on the TV. It also came on full volume by itself a few times.

Gen 4 (1980s) uses an infrared LED and sensor. The remote transmits a carrier at some frequency like 32KHz (blinking on and off rapidly) and then modulates the carrier at a few hundred bits per second. The receiver is an integrated circuit that is tuned to the 32KHz carrier and outputs the bitstream. This is reasonably noise-immune, because there are few mechanical effects that can produce a 32 KHz flicker rate. One of my projects uses these remote sensors, and they are quite sensitive. They don’t work in full sunlight.

We are still using Gen 4 remotes. They are one-way, so the remote has no way to know what state the controlled device is in. You have to aim the remote at the TV, and sometimes devices interfere with each other. Universal remotes require arcane setup codes, and none of them control all the functions of every device. A few manufacturers have used one-way radio frequency control, which avoids the aim problem but also prevents the use of universal remotes.

The mobile device industry, by contrast, has successfully herded all the cats so Bluetooth actually works, at least for common functions. You can generally pair any headset with any phone. As a sysadmin I carry a Bluetooth keyboard for my phone, and that will also pair with just about anything that needs a keyboard.

So why not use Bluetooth for AV remote controls? It has more than enough range, the transceivers are cheap and low power, and there is already a mechanism to negotiate which functions each device can perform. This would allow for two-way remote controls. A universal remote would pair with all your devices, like a headset pairs with your mobile phone, and would map all the buttons automatically.

However, you probably would not need a separate universal remote, because any tablet or smartphone could act as a soft remote, with properly labeled buttons and the ability to execute macros.

Caavo is doing this the hard way because they have to: there is no cooperation between the hardware manufacturers, and each streaming provider wants to own the customer. However, if the mobile phone industry and the car industry can collaborate on Bluetooth, why can’t the home entertainment people do the same? If they don’t, the computer industry will replace them with more friendly devices.

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