I recommend trying to drive the flippers via the arduino too. I had problems in my conversation every time I had a contact switching high voltages. The arcing would mess up signals, etc.

Delay shouldn't be noticeable. Wpc games have up to a 4ms delay and no one complains. Even if you don't want to use the arduino, I'd recommend driving them via a transistor directly from the button instead of having the button switch the high voltage.

Awesome another Arduino conversion. Resurrecting a parts machine is always fun and you get to add your special touches and game rules. I will be watching your progress.

Here is the one I did...
https://pinside.com/pinball/forum/topic/close-encounters-arduino-conversion

Looks like your machine was headless and missing more things than mine was.

What are you plans to resurrect this machine?

I do have another thread on building your own Lamp driver which consist of Shift registers (595's), some transistors (BS170's for now), and it only take 3 pins on the arduino to drive it. All the lamp pins are on the lamp driver board instead of the arduino mega.
The mega drives it with the data, latch and clock pins.

The arduino code is really easy consisting of an attract mode rtn and game play lamp routine.

The sound delay issues might be mitigated by not having sound events associated with the pop bumpers or spinners.
My game has 22 different sound events associated. The arduino triggers a sound event to the raspberry pi and it plays the sound.
It can play multiple channels of sound simultaneously. Examples background theme, knock down target, etc.
The key I found was the sound clips needs to be short.

As far as the solenoid driver board was concerned I ordered a board from Zebasion boards because I was too lazy to build one myself.
His has worked perfectly for the last year or so with no issues.

To cut down on wiring to the mega, I used a switch matrix for play field inputs. It is an 5 x 8 matrix.

One big thing I learned was delay() can cause strange behavior in you game. For example in my reading of the switch matrix use of the delay was a no - no.
This could cause missing of other events when your reading 43 switches at a pass and debouncing them.
The only spot I used delay was on the fire of my solenoids. I am working on some logic now to detect stuck on fire solenoid routine so they don't get burnt out and melt solenoid's.

Another thing I did was have a diagnostic button that exercises every thing to detect bad logic, sound events, solenoid events, switches, burnt out playfield bulbs.

I have always thought about using the mainstream OPP or PRoc and MPF solutions for building my pinball machines but then I never would have learned as much as I did so far.

Really love how you buttoned up your machine, wires are tidy and has a more finished look then my current frankenstien.

Perhaps we can share lessons learned from our arduino creations.

Frogger, what did you user for your transistors/mosfets ?
I am assuminging your machine is using 24 vdc for you solenoids ?

IRL540n. Same as most 2000s games use

Wow, that's real low. I think I'm paying $1+ a piece for them. Never thought of ordering from china.

might be better to just replace with regular coils? Weird that they don't label the resistors

I see from that schematic, Recel did things the El Cheapo way in regards to the flipper coils. I would use a Gottlieb A-5141 flipper coil instead of what is already there.

If you choose to maintain the original Recel coils, wire a 20 ohm @ 25 watts resistor in series with one of the coil lugs on each flipper coil. Watch where you mount the resistor as it will get very hot during game play. You'd need two of those resistors (one for each flipper coil).

Remember, if you run the flipper coils on DC power, you'll need diodes on the coils.

Looking good

I'm so impressed with your conversion and can't believe what you've done at this kind of budget. I purchased a Recel Mr Doom Playfield last week in much the same condition as yours (mine has all of the coils wires bulbs etc). I was going to use it as a display thinking it had gone to far but now I'm thinking of some kind of restoration, much like yours. What would you do? can I use the existing lights connections and plug it up to an Arduino? or do I need a new lighting loom, I was thinking of placing a new LEDs strip under the existing lights to help keeping them in place, much like you've done but preserving the original loom without destroying it and also using your script and changing it to fit mine (think the rules are similar).

I've never done anything like this before and think the scripting might beyond my ability, I'm also worried about the coils and making a solenoid driver board. What do you think? could a novice achieve something like yours?

Cheers PK

playfield back (resized).jpg

playfield top (resized).jpg

Thanks for that, i'll keep you posted on my progress.

Just to make sure I can connect the flippers and slingshots to a 24v power supply? then attach the slingshot pick up to the Arduino for the points information?

If you are interested in considering alternatives, you might want to consider OPP stuff (http://pinballmakers.com/wiki/index.php/OPP). It is not Arduino based, but based off the PSOC4200. (Arduino processors could not match the price and processing at the time). Basically if you order three solenoid wing boards from MezelMods (each wing supports 4 solenoids and I can see 9 solenoids in your pictures) and get $20 in parts from your favorite parts supplier such as Mouser, you will have enough to drive everything on that playfield. Added bonus is the interface to Mission Pinball Framework is already done to control rules, scoring, etc.

If you are interested in learning about Arduinos, how to program them, and how to breadboard stuff, that is also a great way to go.

Just understand there are options. Have fun. These types of projects are great to learn a ton of things for basically no cost, and just have a great time. Good luck.

very cool project. I hope the methods get standardized and people can use these boards to bring back EM machines if parts are not available.

It wouldn't be too hard to even make a modular board set designed to be dropped into everything from EMs straight up to many solid states just by selecting the right peripheral board for the type of setup they have. All solenoid drivers work the same, there's only two real ways to drive lights, etc. I worked on one for a while but I'm not really an electrical engineer

There basically are three standards at this point. (These are simply my opinions, so they may not be correct guesses on prices and such). I'll go from cheapest to most expensive.

OPP (Open pinball project): Hobbyist sort of thing that you have to solder the boards yourself. Everything is through-hole so it is easy to hand solder. To convert an old Dolly Parton (mid to late 80s) machine it cost approximately $60 to drive everything. To fully convert an EM style machine it can run $80 because you have to drive the score reels. (Jeremy has done this, although he eventually switched to PROC). Supported by MPF (Mission Pinball Framework) which has many helper functions to make things like driving score reels, roto-targets, etc much easier. OPP has it own very simple pinball framework if only interested in displaying static images, or no graphics at all. (The Dolly/Van Halen machine was driven by essentially a Pi zero which is too under-powered for MPF in my opinion).

Fast: Slightly less expensive than PROC (or it used to be). It was approximately $450 to convert a machine last time I looked. MPF is the only choice for a pinball framework. Nightmare Before Christmas and a bunch of other homebrews use Fast.

PROC: Used in TNA. I believe it continues to be more expensive than Fast, and it is now approximately $500 to convert a machine. Supported by MPF (script based programming or python code), and also Skeleton framework (c++ based code).

This link has the information from the 2018 MPF survey of who is using what. Since it is the only framework that I know that supports multiple platforms, it gives an interesting comparison (the second message in the thread has the charts about platforms):
https://groups.google.com/forum/#!topic/mpf-users/omWVIaroykQ

Hey there, I'm starting to make progress with my Mr Doom conversion but I'm having problems with the solenoid board. When I connect the ground from the solenoid board the mains 24v power supply stops putting out voltage. I tried unplugging the grounds, which give me voltage but still the switch doesn't trigger the solenoid. I'm using a basic code that I used to turn the lights on and have swapped a led for a solenoid. I get the feeling it's my solenoid board. Some how I think there's a short somewhere. In your diagram your lower 10k resistor looks like its connected to a positive power source but from your description its connected to the ground. Have I got this right? I've put power straight to the solenoids and they all work fine. I'm going straight from solenoids to board (solenoids not connect to the loom).

sorry bother but I'm using you as my guide! this is just a test board, hopefully when I get it right it will be better.

cheers PK

back of board (resized).jpg

top of board (resized).jpg

Still no joy!! made a new board but nothing. I think I understand how the mosfit works with the arduino, opening the gate so the power pass back to the coil and enable it but I loose power from the power supply when the GND is attached to the power supply.

Is my Power Supply up to it? I've tested all the coils by putting 24v pos and neg to the terminals and all work fine. I'm quite lost I can't see whats wrong, I think I might be going mad.

Could I use relays instead? I've seen some on Amazon. Are their any issue with using them? delay or something! why did you go down the mosfit route?

Once I get the solenoids working I think I can start coding! all the switches, lights (LEDs now) are now working, replaced the the burn coil and the end EOS switches on the flippers, new rubbers. I'm excited but going around in circles with the solenoids.
I've also been trying to use the multiplex board as well but no joy there ether.

this is the code I used

int solenoidPin = 4; //This is the output valve on the Arduino

void setup() {
// put your setup code here, to run once:
pinMode(solenoidPin, OUTPUT); //Sets the valve as an output
}

void loop() {
// put your main code here, to run repeatedly:
digitalWrite(solenoidPin, HIGH); //Switch Solenoid ON
delay(2000); //Wait 2 sec
digitalWrite(solenoidPin, LOW); //Switch Solenoid OFF
delay(5000); //Wait 5 sec
}

PK

20181024_205358 (resized).jpg

20181024_205612 (resized).jpg

front (resized).jpg

front_LI (resized).jpg

new back (resized).jpg

Can you draw it up as a schematic somehow? It's hard to follow your pictures

Do you lose power as soon as you hook it up, or only once the arduino fires it? What if you arduino is left unplugged from everything?

There is no ground between the arduino and the breadboard. Your arduino's ground is at a different voltage than your power supply's (24V) ground. You must tie those two grounds together. Try reading this blog post and see if it makes sense:
https://openpinballproject.wordpress.com/2016/11/16/111521-why-is-it-so-hard-to-explain-grounding/

I have tried putting a pin from the GND on the board back to the arduino gnd with no luck. Quick question, there's 3 GNDs on the arduino, are they all the same?

Here's a really bad example of my board but I think it's about right

bread (resized).jpg

The arduino, breadboard, and the 24V grounds all need to be connected

I'm think I tried connecting the ground back to the arduino as well as the power supply. I'll try again tomorrow and in the meantime I'll read that grounding post.

Thanks for the help I'm sure I'll get my head around it sooner or later. when I do i'll maybe start my own blog and not hijack this, sorry Frogger!

Cheers PK

when the arduino has been disconnected from the usb power I get power to the coil! it doesnt activate but power is going through, I've just run the GND from the board to the arduino and also tried arduino back to the power supply GND. Still no joy. I might try a pre built relay. I dont think my bread board making is up to scratch or my power supply is not up to it.

new board 2 (resized).jpg

the lower resistor in your diagram looks like it goes to the positive side of the coil and not to ground is that right?

I've driven whole machines off breadboards, no problem. And if your supply can power it when you fire it manually it should work fine with the mosfet

Do I need to connect the negative side of the power supply to anything (probably a very stupid question)?

Tie all grounds together. At one point would be good. I would solder a ground wire onto the ground pin solder pad on the Arduino board. Using the header sockets for ground is not very solid and will cause issues. The grounds on the Arduino are all the same.

Hey Frogger1108 I worked up a set of arduino mini dmds for a Nugent upgrade I am working on. I'm more than happy to share2018-03-28 17.05.00 (resized).jpg

You got a part number for those grids? I've been looking for some...

Finally it's working!!!!!!! Ahhhhhhhhhhh Sorry for being such a zombie!! Mr Doom is slowly coming back to life. Thanks for all the help

MAX7219. They are SPI but I found that I can't run more than 12 8X8 from a pair of pins on the mini and have enough power to run the 13th display.

Here's a set on ebay slightly more expensive than I paid. ebay.com link: Dot LED Matrix MAX7219 MCU Control LED 4 In 1 Display Module for Arduino 5x