I recently bought two old curling scoreboards for the dodgeball league I am starting up (See picture).
It has two score displays, a period/set counter, and two countdown timers. I felt this scoreboard was perfect since the style of dodgeball I am running uses 40 minute game time and a separate 3 minute set time. The problem I am having is that I need both timers to run at the same time, except in curing when one timer starts the other one stops, so that is what happens with this scoarbaord.
Ideally I would like to program an Arduino and attach it to the current buttons on the old controller. A brain transplant if you will.
I am new to Ardiuno and would rather not waste money buying parts I don't need during trial and error. I am ok with Python programming and have supports in that aspect. The controller connector is a 4-pin XLR type, pinouts are:
Pin 1 – V+ (DC)
Pin 2 – V- (DC)
Pin 3 – RS + (communication)
Pin 4 – RS – (communication)
My question is, other than an Ardiuno (obviously) which I did purchase one of those stater kits with various parts, what other equipment might I need to accomplish this task? Where do I even start with this?
The hardest part will be the LED interface, it will be extremely difficult to drive that unless you have a schematic or know exactly how it is wired into the system.
If that connector is the only thing between the button box and the scoreboard then my guess is that both have controllers with a serial connection and protocol to send command messages across.
Arduino can run serial but may need a cheap serial chip to send to the scoreboard. It also needs to know what to send. it may be findable and yes that would make it simpler than rewiring the scoreboard.
Start by determining the voltage levels of the 4 pins. With luck they will be in the 5 volt range. If not figure out how to get the communication lines to a 5 volt range.
Then get one one of the $15 USB 8 channel logic analyzers from Amazon or Ebay and figure out the signals sent from the various buttons on the control unit. Duplicate those with an Arduino and there you go.
You could possibly, eventually decode the signals with an Arduino, but it will be much less frustrating to use a logic analyzer.
So this means you are familiar with the basic concepts of what variables. if-conditions, functions, parameters are?
Are you familiar witt the basic concept how serial datatransmission is done?
I did not fully understand how you want to act the display
there are for digits in the first row and four digits in the second row
and this is left and right.
Can you describe what the display is doing with the existing controller
in a way
left 1st line countdown active right 1st line countdown inactive
left 2nd line countdown .... etc.
Can you open the display with the leds without cutting/breaking anything?
If yes
If you open the display with the leds
Can you see how the LEDs are wired ?
Can you post a picture of the opened backside?
At the moment wie know almost nothing about how this display works.
Depending on how it works it might be easier to directly drive each LED-segement directly with a MOS-FET-transistor.
But this is only one option among many others.
Analysing the signals on the 4-pin connector looks like a very good approach.
These logic analysers are mostly named 24 MHz 8 Ch logic analyser.
You can read in the signals to a PC with the software pulseView from sigrok.
PulseView is able to translate all the bitbanging low high into a lot of protocols.
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