Stargate Pinball Reactive LED Ring Mod/Hack! 8


If you want to see more of the whole process of fixing, restoring and customizing this Stargate Pinball machine, you can look at my post on the subject here : https://www.stacydevino.com/2017/04/fixing-and-restoring-a-stargate-pinball-machine-with-3d-printed-parts/

 

The Game while in play at TPF

 

The game already looked great, played extremely fast because of all of the polishing and slicking of all the ramps and playfield, but that Stargate Ring in the top-box looked sad. This is a game from 1994-5, so LEDs existed but they were expensive and in all honesty the folks at Gottlieb knew this game would be their swan song so the Ring of Lights was not high on their “learn a new skill” meter, so they are INCANDESCENT BULBS IN SERIAL!. I mean, even the board were still using a 6502-based processor from the mid 70’s. These boards were probably designed to take advantage of the parts that they had and the code already written for the System 80 boards used from 1980-1990. Often these die (mine was working, but obviously replaced the original), and people resplace them with Blue Colored LED Rope meant to run at 18-24V. LEDs are required because the original runs at ~20V DC with the occasional 6.3V AC Pulse (when flashing).

In the game, there are some moments that the ring flashes. That means that we can capture that digitally! But…… ~20V DC and 6.3V AC blips are NOT GOOD to capture in a 5v microcontroller! So, in this design I am actually using an adjustable regulator. Part of using this as well is that it gives me fine tuned control in case of power fluctuation in the machine which causes odd ghosting on the ring replacements that other people have made. We want it to trigger only when needed.

In testing code, I found that the LEDs chosen (SK6812) will blind you if running at full color gamut or pure white will BLIND you while playing the game. So, in many cases, the code actually does a fast modulation that has only every other LED pulsing so it uses a POV effect! Side bonus is that this means I could run this directly off of the 12V unregulated input line in the game without blowing the fuse since the whole thing will run on ~2A at 5V in peak power.

Operation

Startup:

First Stargate Bootup-sequence, then Stargate Blue color spectrum wipe ignition, and finally the RGB Swirl Activated Mode

On Flash/interactive mode (interrupt driven)

Flashing White Theater Chase (can be continually activated), followed by the Startup Sequence

Standby 

RGB Swirl

Parts:

  • Ajustable Power regulators (need 2) : https://www.amazon.com/gp/product/B01GJ0SC2C/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
  • 144led 1m long SK6812 LED strip (with extra connectors) https://www.amazon.com/BTF-LIGHTING-Individually-Addressable-Flexible-Waterproof/dp/B01N2PCIB9/ref=sr_1_2?ie=UTF8&qid=1491100447&sr=8-2-spons&keywords=sk6812&psc=1
  • Silicone Tubing with 3/8″ inner diameter : https://www.amazon.com/gp/product/B00DYAFIRI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
  • Arduino Mego or Clone (or one of the ARM-based Arduino-code boards), needed primarily for the RAM as you are addressing 144 LEDs quickly.
  • 20-22AWG wire
  • Scissors
  • 8 Clear Zip-ties
  • Snips
  • Tiny Flat-head screwdriver

Optional: 

Arduino Prototype Shield (my design was made so each piece could be disconnected fully for debugging and switching to the original ring if this just did not work reliably… but it does so its optional) https://www.amazon.com/gp/product/B00Q9YB7PI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

Pre-work : Remove the original ring, attached plastic holder, and open up the latch to the backbox  boards/PCBs

 

Step 1

Download Neopixel library and Load Software on Arduino Board  (available here : https://github.com/childofthehorn/stargate_led_ring)

 

Step 2

Test the Code by plugging in the SK6812 LED strip PWR(red)-GND(black)-IO(green wire) to D6 on the Arduino-based board (you will want to add additional power through another USB port or 5V power supply to the 5V line directly on the LED strip).

Step 3

Solder in the regulator to the 12V unregulated line (Power and Ground) to the 12V input on the 12V-5V Main Power Board in the top back-box. This will require that you unscrew the board from the backbox and add the wires to the underside of the board. Now, turn on the game and use the tiny screwdriver to adjust the output from the regulator to 5V. (In my design I used a slightly different main power regulator because I needed to monitor voltage drop while in use so it has an LED display of the system input voltage seen in pictures).

Step 4

Solder and connect in the Ring activator voltage to the 2nd regulator and adjust the output voltage when active to 3.0-3.2V output. This will allow the uC to read it when it drops to ~2.3-2.0V and triggers the interrupt.

Step 5

Solder the 5V regulated output (game off) to the 5V line in the Arduino or the 5V area on the Prototyping shield. Do the same with the GND.

Step 6

Solder the Ring regulated output positive to the Arduino D2 (digital 2) pin or onto the Portotyping Shield. Connect the GND to the GND on the Arduino.

Step 7

Carefully cut the excess edging on the SK6812 LED strip if it has any (only the center actually runs the wire on most of these strips. remove waterproofing strip if present.

Step 8

Spend about 2-3 hours pushing the SK6812 LED strip through the silicone tubing (you want that diffused look) very slowly as to not fold or bend or otherwise snap the LED strip.

Step 9

Zip-Tie-in and Orient the strip like this picture

Step 10

Solder the LED strip pigtail connector to the Arduino where PWR goes to 5V and GND to GND, the Green Digital connector will go to Pin D6 (digital 6).

Step 11

Connect everything together and put into the back of the front LED area of the backbox as shown.

Step 12

Turn on and Enjoy!

 

Standby Mode

 


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8 thoughts on “Stargate Pinball Reactive LED Ring Mod/Hack!

  • Russell Myers

    Hi, I am following your thread on your Stargate resto and it looks great.

    1. I want to print the switch bracket. I have downloaded the stl file from Thingiverse and am on Shapeways and I have no idea what material or others options to choose (never did this before)

    2. I really like how your DIY inside cabinet starfield decals turned out – where do I get that material and how much do I buy?

    Thanks!!

    RussMyers

    • childofthehorn Post author

      1. PLA or ABS or PETG, all will be more than fine with a 2mm wall and 20% infill.
      2. 150mm wide Galaxy Print Car/Motorcycle Vinyl Wrap. You can get 1 roll to cover the entire thing for like $15 shipped and it will be very high quality.

  • Gary

    Great mod! Thanks for posting the details. I’m getting ready to do this mod on my Stargate and wanted to touch base before to see if there are any changes not listed in your details. One thing I noticed is you mentioned how bright the LED’s are… it looks like they have a 30 LED model available as opposed to the 60, would you recommend going with that? Also, there is a non-waterproof model available. Was the waterproof model used for a reason?

    • childofthehorn Post author

      So, In the mod, the code is actually flashing the LEDs so fast that the human eye cannot tell. That way we can get the full color gamut and have the LEDs really close together. The 30/m LEDs won’t look nice and continuous like they do in the video. They are more expensive, but worth it!. If you want, you can also use Natural Teflon Tubing instead of Silicone. It will be MUCH easier to work with.

  • Dan

    Hey Stacy, I’m loving the idea of this mod! My ring hasn’t worked for years, and I finally got off my behind and ordered the parts to try and replicate your work. My level of knowledge isn’t as high as yours though, so may I ask if you have any more pictures of where exactly the wires hook up on both the MEGA (to make sure I my understanding of which ones are the “D” pins matches yours), and to the Stargate (the power connection).
    Cheers,
    Dan

    • childofthehorn Post author

      For Power, I have a a 5V DC-DC regulator board connected up to the GI (general illumination) power and ground. That would be the same Power/Ground used for the white background bulbs.

      The Arduino has the pins labeled, you can see the matching pin name in the *.ino file at the top. You don’t HAVE to use the shield like I did, but I did so because I wanted to be able to replace the processor/main board if anything ever went wrong or for upgrades in the future as well as ease of programming since I can just pop it off to try new code rather than get a long USB cable and try to push it in there.

      For info, I am using the Arduino Mega because of the speed of the processor and because it simply runs the code better without having to worry about ROM space.

  • frank

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    Here is Frank from Haobo Electronic, a Chinese led lights

    factory.
    We do all kinds of pinball machine led bulbs,
    Do you need the pinball leds at present?

    If need the newest pricelist for reference please do not

    hesitate to contact me at: hb-frank@hotmail.com
    Thank you and best regards,
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  • Mike J Willett

    Hi Stacy,

    I love what you have done with the Star Gate Ring and have decided to do this to my Star Gate pinball machine. I have purchased all the parts you have posted and are waiting for them to arrive. I am a bit confused as to where all the connections go on the reading. (two power regulators etc.) I prefer a diagram (schematic). I have viewed your readings many times and wanted to know if you could just draw a diagram/schematic out showing all the connections with each components. That is what pins on the driver board you get power from, each power regulators power connections and their out going connections showing what voltages are at. The connections into the Arduino Mego board and out connections to the LED’s. Would opt out on the optional shield board as this appears not to be needed. This would be very helpful and does not have to be perfect, but would be a bit easier to understand than words. mikespinballmachines@gmail.com

    Let me know……Thanks…Mike J Willett