Modifiable TV - Page 1
Forum section: electronics / general

author: dtnieberding
author_rank: Newbie
timestamp: February 06, 2025, 01:02:35 pm
content: I'm looking to build a special TV for a handicap person. It needs to be controlled entirely by a single button. The button will power it on (if off), and will cycle through video files with each press. A motion sensor (or something similar) will power off the TV when there's no motion (he leaves the room).I need GPIO for the button, and an input for the motion sensor.My plan was to use any TV and a raspberry pi. The raspberry pi can send CEC commands through HDMI. However, I thought maybe there's a TV model that is already built on something equivalent to the raspberry pi, and will allow me to modify it. Does anyone know of such a TV model? Perhaps one that is designed for digital signage.I'm also open to any other suggestions for the project.

author: bostonman
author_rank: Super Contributor
timestamp: February 07, 2025, 02:45:21 am
content: I'm sure explaining why it needs to be a single button is difficult, but can it be a four position push button such as a game controller?This way the person can select a menu option and scroll up/down/left/right and push to select.

author: antenna
author_rank: Frequent Contributor
timestamp: February 07, 2025, 05:21:23 am
content: If instead of controlling the TV via HDMI, you could connect an IR LED to an arduino and save the PI for a more demanding project. This would allow it to be on the chair, instead of tethered to the TV.

author: ledtester
author_rank: Super Contributor
timestamp: February 07, 2025, 06:33:22 am
content: Quote from: dtnieberding on February 06, 2025, 01:02:35 pmIf you didn't have GPIO you could easily create a USB HID (human interface device) with a small microcontroller that would translate the button and motion sensor into keystrokes (or joystick controller button presses). Just google "make Arduino usb keyboard". Then you would only need USB.QuoteI think you'll find developing the software a lot harder than doing it with a Pi. Also, using a Pi would make it very easy to change the display device since you only communicating over standard interfaces.If you absolutely can't use a Pi, you might be able to implement your project as an app on a smart TV. Maybe an Android TV app and then you might be able to run your app on TVs based on Android TV. Of course, you would first have to spend a lot of time learning that development environment. Your application is dead simple on a Pi so I would just with that.Update:Even simpler that the "Arduino keyboard" idea... just take an existing USB keyboard and wire up the button to "press" one of the keys by closing the same circuit that the physical key closes when pressed. Ditto for the motion sensor.

author: tooki
author_rank: Super Contributor
timestamp: February 07, 2025, 09:41:22 am
content: Quote from: dtnieberding on February 06, 2025, 01:02:35 pmOne avenue I’d look into before building anything yourself is the Apple TV settop box: it has support for one-button accessibility out of the box, using Apple’s OS-level switch support. Start here:https://support.apple.com/en-mt/guide/tv/atvbc96e032c/tvosWhat I don’t know is if there’s any ability for the switch to turn on the Apple TV box. (If so, that’s all you’d need, since turning on the Apple TV will automatically turn on the TV set via HDMI CEC, and the box has the ability to turn off the TV, too.)

author: Bobson
author_rank: Regular Contributor
timestamp: February 07, 2025, 11:02:48 am
content: Quote from: antenna on February 07, 2025, 05:21:23 amIt would be very unreliable. IR commands are menu-position dependent, while HDMI CEC are not.

author: tooki
author_rank: Super Contributor
timestamp: February 07, 2025, 11:48:07 am
content: Quote from: Bobson on February 07, 2025, 11:02:48 amWhile I actually agree with your recommendation to use CEC, it should be said that IR command sets vary wildly, and typically include direct commands even if the included IR remote control doesn’t have buttons for them. (For example, the included remote might not have buttons for specific inputs, but the command set might, allowing “absolute” control without menus.) So you can’t make blanket statements like “IR commands are menu-position dependent” because that isn’t true as a blanket statement. It might be true for some devices, or it might be truejust for the included remote control, but it’s not true for all IR.

author: Bud
author_rank: Super Contributor
timestamp: February 07, 2025, 05:30:17 pm
content: If the person can wave their hand, check ST Guesture Recognition sensors.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 08, 2025, 10:44:13 pm
content: If you use a display that supports DPMS, make use of that feature.

author: geggi1
author_rank: Frequent Contributor
timestamp: February 09, 2025, 08:45:42 am
content: If this person can use voice thera are models that can be contolled directly or by external hardware.

author: dtnieberding
author_rank: Newbie
timestamp: February 12, 2025, 05:53:42 pm
content: Sorry for the delayed response. I thought I would get email notifications, but I guess not.The handicap person is severely disabled. He can't use a game controller, or a tv remote. He doesn't have the motor skills. He also can't use any motion control or voice control. However, he can understand simple things, like operating a light switch on the wall to see the light turn on, or pressing a large button to see the TV change. He enjoys watching some TV programs but has to rely on caretakers to turn them on. The goal with this project is to give him some independence in choosing to watch TV.Thanks everyone for all of the suggestions! I'm still thinking the RaspberryPi method is my best option.I was thinking of using a giant arcade button. Couple problems with that. Most of the buttons seem to be meant to be mounted on a panel. It will need to be hard wired. A self-contained wireless button would work better. Something like the Staples Easy Button. Does anybody know of a self-contained wireless giant arcade button? If not, I could buy the Staples button and modify it to transmit a wireless signal.

author: edavid
author_rank: Super Contributor
timestamp: February 12, 2025, 06:54:52 pm
content: Quote from: dtnieberding on February 12, 2025, 05:53:42 pmDid you click the Notify button on the thread?Anyway, what does the client actually watch? If it is (or could be) local files, Internet sources, even OTA stations, it's pretty easy to build your own "TV" and control it however you want. If there has to be a cable box involved, that's more of a problem.

author: dtnieberding
author_rank: Newbie
timestamp: February 12, 2025, 10:27:00 pm
content: I'm on a mobile device and it does not show a "notify" option on the mobile version of this site. When I switched it to full site, notify showed up. So now I should get notified. Every other forum I've been on, has email notifications enabled by default.He watches a select few children's shows, and some game shows. I wasn't planning on factoring in any broadcast TV, or streaming. He should be fine with a bunch of video files.

author: bostonman
author_rank: Super Contributor
timestamp: February 12, 2025, 11:15:23 pm
content: Seems as if you have quite a challenge to help this person.In a previous message I suggested a game controller, but, as you stated, that won't work. The large button seems like it will be the best option.Another idea I had earlier was whether the person uses a wheelchair (most likely not based on your description) and whether a floor switch could be implemented. Maybe it engages when driven over, has a X second delay so it can't turn on/off quickly should the wheel remain on it, etc...Anyway, good luck and nice you're trying to help this person.

author: edavid
author_rank: Super Contributor
timestamp: February 12, 2025, 11:42:45 pm
content: Quote from: dtnieberding on February 12, 2025, 10:27:00 pmThat makes it much simpler. I think you could do what you want pretty easily with the "PiPresents" kiosk software package.Just store the video files on the RPi and let a GPIO pin advance to the next file and play it. You wouldn't have to control the TV/monitor at all.For the wireless button, it might work to buy a wireless USB remote like the ones sold for OSMC, and connect a big button to it. You might also be able to adapt a wireless doorbell.

author: dtnieberding
author_rank: Newbie
timestamp: February 13, 2025, 12:12:06 am
content: Quote from: bostonman on February 12, 2025, 11:15:23 pm.I like the idea, but he does not use a wheelchair. He can walk

author: dtnieberding
author_rank: Newbie
timestamp: February 13, 2025, 12:15:40 am
content: Quote from: edavid on February 12, 2025, 11:42:45 pmI've not heard of PiPresents before this, but I just looked it up and I think that would work well.I'm checking out wireless USB remotes now. Thanks for the suggestions!

author: Doctorandus_P
author_rank: Super Contributor
timestamp: March 01, 2025, 09:11:20 am
content: Quote from: dtnieberding on February 13, 2025, 12:12:06 amThen, maybe some foot pedals work? Some sort of plate with left, right, up, down.I have always abhorred the direction of attempting to minimize the number of buttons on a user interface. I still have nightmares from those alarm clocks you have to advance 23 hours and 59 minutes because you released a button 2ms to late, or a jittery button that added another minute while attempting to set the clock.

author: bostonman
author_rank: Super Contributor
timestamp: March 02, 2025, 03:21:59 pm
content: Quotehahhah I have an alarm clock over three-decades old and it has a similar issue. If releasing the alarm time set button at just the right moment while pushing the hour (or maybe minute) button, it advances the current time of day by an hour.Thankfully I've always caught it.