Reverse-Engineering a Scoreboard Display

https://hardfault.life/p/big-seven-segment

by ryukoposting • 2 years ago

99 17 2 years ago

ben7799• 2 years ago

If you've ever had the pleasure of running a Daktronics scoreboard... Holy cow is there some bad UI there!

Looks like a 1970s military interface. With cards that you overlay on the controller for different sports, but the schools, etc.. lose the cards.

So many operations require strange & confusing sequences of button presses.

At least with basketball professional referees often understand the UI well and can help out in a pinch, but these things are really really hard for volunteers to figure out.

There are some newer ones that are self contained where the computer & scoreboard are integrated and sit on the desk with the scorers and timekeeper. Those have the lovely design that the horn/buzzer is right in the unit and it blows everyone's ears out when it goes off.

ulf-77723• 2 years ago

Not sure if there are a lot of different producers in europe, but I know that it’s not much easier to use the boards in german gyms. Have seen a couple of them so far. The interesting thing happening here is that the boards stay in place but they get new interfaces to use them with smartphone apps.

roamerz• 2 years ago

For the last few years they have had a bluetooth controller and a companion phone app. The other beauty of these is they have a data out port that is able stream the data for other applications such as overlaying the score on a live broadcast. I know because I retrofitted a sports park a while back with steaming audio/video/scoreboard data. The people at Daktronics were super easy to work with and what a super fun project.

toast0• 2 years ago

I only interact with these at ice rinks; they've all got laminated cheat sheets pasted to to score table; and the control box is fixed in place. not like in a high school gym where the control box has to come and go.

Our home rink was built in ~2000 and had a "high tech" system with a palm pilot driving the scoreboard. It got replaced by a computer running a java webserver and internet explorer maybe a decade ago. A lot more friendly for a novice, but the daktronic wired remote switch to start and stop the clock is a lot nicer than having to hit a small click target area. And I could see a skilled operator getting to the point where they could touch type the control box; gotta have eyes on the screen for the web based system (no hotkeys; or at least they're not known by the team parents)

patmorgan23• 2 years ago

If you're gonna go screen and keyboard might as well go the CLI route. So people could touch type.

You can still have the web based display and click targets, and have them send the commands to an in-browser terminal/command log. This allows people to learn the CLI while exploring the GUI.

owlninja• 2 years ago

I have been volun-told to keep score at a few youth baseball games on these. The first time I definitely fumbled around keeping the count straight - which was always quickly pointed out to me from the stands :)

tyingq• 2 years ago

If this is something you want to play with, but these high end Daktronics units are too expensive, search AliExpress for "gas station price display".

Here's, for example, a 12 inch 7-segment high single digit for ~$38, including shipping: https://www.aliexpress.us/item/3256802774192337.html

You can use their driver boards, or just scale up a cheap 7-segment driver with a few extra parts to drive the 12v it wants for each segment.

pavel_lishin• 2 years ago

If you ever see a car hit a light pole with a crosswalk sign, you can also ask the city if you can take it home; they have very similar stuff inside, including a double seven-digit display.

It's not really "programmable", though - the only thing you can set is the duration of the walk/stop cycle, and how long the warning countdown lasts, and iirc it's powered by some pretty high voltages. But nothing is stopping you from connecting to the LEDs directly, via some pins that you can use a ribbon cable to connect to.

russellbeattie• 2 years ago

Interesting I've recently noticed these popping up all over at those independent gas stations that are somehow substantially cheaper than national chains. This type of display must have just become easily available or made 10x cheaper or something.

ryukoposting2• 2 years ago

There seems to be a cottage industry of Chinese manufacturers making super-cheap products out of LEDs that would have failed QA at the LED factory. The LEDs often still turn on, but they're quite dim and will die very quickly.

orenlindsey• 2 years ago

I love these stories of "reverse engineering [insert name here] display," there's so many of them.

hinkley• 2 years ago

I wonder what fraction of Arduino/RPi displays are purchased with plans to interface with all of these proprietary video displays.

TheWizardOfUgh• 2 years ago

I love seeing stuff like this. It almost makes me want to try to reverse engineer the one at my uni. It's just sitting unused. It would be cool to try to reverse engineer it and get it working again.

The again the one I want to try actually displays video? So it's probably way harder. I wish I could find more documentation about how daktronics systems work.

MeteorMarc• 2 years ago

But what was the purpose of the ninth input pin mentioned?

ryukoposting2• 2 years ago

OP here - It's not connected to anything. I'm assuming it would be used for a decimal point or a colon on a different model.

lofaszvanitt• 2 years ago

The bane of these systems are these wirings. Somehow we have to nuke the wires. It would help tremendously if it's governed by software.

nyanpasu64• 2 years ago

Please excuse the horrendous SMD soldering work. I haven’t done any SMD soldering in quite a while, and this was my first time ever trying to hand-solder teeny-tiny 0603 components. It won’t be my last time, either - I ordered 50 of them, and I only needed 10 to assemble this board.

You should touch up the joints with external flux.

Reverse-Engineering a Scoreboard Display

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