So the CobraPin has the direct switches and the matrix. Out of curiosity, how hard is it to setup a matrix myself?

If could do an 8x8 matrix as well, I'd only need one blue pill board. Obviously not breaking bank buying another board, just think it'd be cool to get by on one.

My requirements are;

1-2 blue pills for,

At most 50 serial LEDs

28 playfield switches (including the pop bumperish device, which goes to the solenoid board, right?

6 cabinet switches (the flippers, the drain, the shooter lane, the tilt bob, and the start button)
Probably forgetting something there

One solenoid board

And a separate motor driver board (I only really need directional control on one of the motors, but dual drivers for little robots seem pretty affordable.)

I have also been wondering if there is something in the car stereo/accessory area that would fulfill my 12v power filter needs. Going to do some digging.

Fair enough. Direct switches it is

So just a few more questions.

On the CobraPin, I could drive a motor with one of the coil outputs or on a dual relay board attached to the relay control output for directional control, correct?

When determining needed current for the power supply, is it the sum of draw from all the solenoids, LEDs, etc.? Just the highest one?

Edit: Nevermind the second one. I think I figured it out.

Thank you all so much! I really appreciates the help.

So here's the plan:

CobraPin controller.

Something like this for a dual relay board to control a 12v dc motor in two directions.
https://www.amazon.com/dp/B0057OC6D8/ref=cm_sw_r_cp_awdb_imm_B1JQSEWX81EA9YZYR0HH

Meanwell RD-125a power supply.
https://www.meanwell-web.com/en-gb/ac-dc-dual-output-enclosed-power-supply-output-rd--125a

12v going to coil power input, 5v to that input. I think there should be enough 5v left to power a single board computer to be the host when the game is finalized (maybe some small speakers too?)

Any red flags on that idea?

Turns out, when you have free time, you can actually do things. Who knew?

Grandparent came to visit and watch my kids, so I finally had a chance to chop up a sheet of plywood that's been sitting there for ages. I made frames for my backbox and my son's pachinko. I think the box joints came out well, considering I don't have a table saw or router.

Game Room in ProgressBox joint Close Up

P.S. As no one replied "NOOO!! DON'T!!! OH THE HUMANITY!..." on my last post, I think I'm going to start ordering some of those parts.

Admittedly, 12v is weak. You can see it in the video. The pop and spinning flipper could use some extra oomph.

I didn't expect any of this to actually work early on, so I just grabbed an old 12v wall supply from the e waste bin. Things kept working though and I ended up with this playfield and mechs built around 12v.

So given the choice between an underpowered game or changing the flow/possibly breaking some of my mechs, I'm leaning towards underpowered.

I couldn't tell if 24v is the minimum for the cobrapin, or if it's just listed as that because 24v is the common minimum and anything under is kinda stupid. But I never claimed to be smart

Definitely have to watch that video from Jab.

That is a very good point.

So the solenoids are labelled as 12v, but there are seemingly identical solenoids on ebay/ali express labeled or listed as 24v. The spinning flipper motor has no labels! Who knows what that can handle? It was listed as 12v when I bought it, but I don't have any spec sheets. The shaker motor is listed as 24v compatible, so there's that I guess.

Motor1 (resized).jpgSolenoid1 (resized).jpgSolenoid2 (resized).jpg

The balls are standard size. Had to do at least one thing the normal way.

Got confirmation from @cobra18t. 12v is an option, just an uncommon choice. Probably good info for anyone building a mini pinball.

Look what came in the mail today! May the pinball gods be merciful and I don't break it.

PXL_20210924_170013209 (resized).jpg

Well, I was cutting and crimping all day. Connected some switches, feeling smart and... I lost my nerve when I was going to connect power.

So the cobrapin board has 2 vin and 2 gnd for both the high voltage and 5v. The super helpful cobrapin wiring diagram (not sarcasm, love that thing!) shows two red / two black going into presumably separate channels on the PSU.

My psu has only one channel for each voltage and com.
PSU

Should I run two wires into the PSU channel or can I use 1 vin and 1 gnd on the board inputs?

Thanks! Confidence restored.

Argh! Thar She Glows!!!

default blue glowGI and Bomb lights

LEDs are in! I'll actually have to think about an attract show now.

Even more progress (two things in one week, crazy right?) The monitor is mounted in the backbox. You can even see a little bit of my art, the part I don't entirely suck at.

backbox monitor

Obligatory tangled mess of wires photo.

playfield underside

Everything but the motors are wired up. I have a few questions on that, but I'm going to test what I have first.

Sorry for the junk video.

It actually kinda works! I know this is pretty small potatoes compared to amazing work the rest of you are making, but as my first DIY electronics project, it's a pretty big deal for me.

Obviously, without the mini flipper motor running it's missing a big piece of the gameplay, but it lights up/keeps score/flips balls. Minimum definition of Pinball achieved!

Alright, motor talk.

1. Easy question, Shaker motor. Do I need to add a flyback diode to it like I did the coils?

2. More challenging questions, miniflip motor. I'm using a relay module and was going to wire it up like this.

relay module wiring diagram

Any reason I shouldn't do it that way?

I'm assuming that I should be running power directly from the supply, not the HV on the Cobrapin board, right?

On the software side, how do I control the relay module in MPF?

I'm reading that the motor device requires position switches and a reset position. I don't have those. It just needs to spin when triggered (randomly clockwise or counterclockwise, but that's a later issue.)

How would one configure a spinning disc like on Whirlwind, Fireball, Tron etc.? Seems like that would be similar to my needs.

Sorry if I'm not understanding the obvious. So I could use the relay numbers (rly0 and rly1) in the coil player?

Yeah, according to the pinballmakers text:

"Connecting the middle and upper pads gives control of the relay programmatically to MPF by using the 1-0-1 coil output."

For some reason, I thought the relay outputs (rly0 and rly1) could only be configured as digital outputs, using them as coils in coil player would be alot easier for me.

Good news is that my little shaker motor works pretty well and the family visiting for the holiday had fun with it, despite it's unfinished state.

Bad news is that I have more questions. Sorry folks, especially @jabdoa, seems like all I do is bother you.

1. If a ball goes missing from a device and mpf adds it back to the playfield ball count, is that ball a "ball_in_play"?

I'm trying to create a "just go straight to multiball" failsafe for the rare problem that one of the locked balls gets dislodged. Testing virtually, I'm getting some issues in multiball; extra balls added from the trough or end of ball drains when there is still one on the playfield. Logs seem to indicate a mismatch of playfield balls and balls in play.

2. Can I change the configured eject coil on a ball device in game?

Example, if I had Coil X as the default eject coil for the device, but an event triggers it to change to Coil Y.

A ball device can't have multiple eject coils and has to be configured as either eject,hold, or mechanical eject, right?

I thought that might work too, but mpf tells me that mechanically ejected devices cannot have more than one switch (mine has 5). I suppose I could split it up into multiple ball devices.

Happy new year everyone! Not alot of progress to report. I did get a chance to try out the relay output, but didn't have any luck.

I soldered together both of the the upper and middle pads on the Cobrapin board like the pinballmakers picture says to do for control through the 1-0-1 output.

cobrapin soldering points

In the config, I mapped the coil to the name rly0. Mpf threw an assertion error on start up. Tried 1-0-1, program locked up when the coil was activated. Is there a name that I'm supposed to be using?

I saw this on the MPF Users Google group,

"The built in connections only allow control from the 1-0-1 coil output or control from the processor board USB receiving power. If you want two separate programmatically controlled relays, you have to wire another pin from the coil outputs."

It seems like 1-0-1 can control only one of the relays?

So I tried to desolder one of the pairs and... I wrecked it. Ruined the pads on one of them.

I'm just going to settle for one direction of rotation, directly from the coil outputs.

(Sad Trombone)

It's not so bad. Everything else seems to work fine. I just can't use one of relay outputs anymore.

CW rotation disperses the balls nicely in a wide area, whereas CCW mostly hurls them down to the left flipper. So doing just CW is fine, the random directions would have been just a little extra surprise.

I'm kinda glad to be moving on to different problems.

Finally back. Solved my ball count problem and fixed a few playfield issues that had been bothering me. Multiball mode is working! Rules need more testing, but I mostly like them so far.

Here is the current ruleset, with another picture of the playfield for reference;

Full Playfield

At the top are the BLAM lanes. Completing the lanes increases the blast award score (10, 25, 50, 100). Below those is the kick out "Oomph" hole increases the multiplier for the blast award (2x, 3x,5x).

The blast award is earned at the start of multiball. Balls are locked under the bomb. Once a ball is locked a fuse timer starts The multiball begins when 3 balls are locked or the fuse timer runs out. Time is added to the fuse by locking another ball or hitting the spinner on the left.

The spinner also cycles the target for sabotage. During multiball, shooting a ball into the oomph hole will sabotage the targeted player, possibly yourself. Currently set to -10% of the player's score, requires a lot of testing to find that nice balance of fairness and cruelty.

Blast award is (# of locked balls x BLAM score x oomph multiplier) for a current maximum of 1500.

Down and right from the kickout is the captive ball. Targets adds +1 to all targets and lanes (most are 1 or 2 points, so a potential +3 increase is noticable but I wonder if it should be more.)

Lighting the captive ball targets and the midfield stand up targets adds to the jackpot in multiball. During multiball each formerly lit stand up turns flashing. A flashing target awards a mini jackpot.

Mini jackpot is (5 x # of lit stand up targets at multiball start x # of balls in play) for a maximum of 105

Jackpot is achieved by clearing all of flashing stand-ups. It is (mini jackpot value x # of lit stand up targets at multiball start) for a maximum of 735.

The "fizzle" drop targets are the safety net. Clearing the bank provides you with percentage (25% ,50%,75%) on drain of what would have been your blast award and your jackpot.

Hitting the pop bumper awards the joke "Pop" Art bonus on drain. It's the bumper score (including the captive ball increase) x the # of times the bumper has been hit in the player's ball/game.

Clearing the lower "phew" lanes restarts ball save.

Thoughts and critiques? I was thinking about adding a second multiball and/or a mini wizard mode.