Db-25, db-15, vga?


#1

Hey guys, I’m building a PCB independent stick and I had some questions about connectors.

I’ve seen people use DB-25 connectors but would I be able to use a DB-15 connector if I’m only gonna need 15 connections?

  1. up
  2. down
  3. left
  4. right
  5. A
  6. B
  7. X
  8. Y
  9. LT
  10. RT
  11. LB
  12. RB
  13. Guide
  14. Start
  15. Common ground

Are all of the pins in a D-sub connector independent? Are any pins common?

Also, I was wondering about 15-pin VGA. I gutted one and it looks like there is a large shielding going around all of the wires and then some smaller wires had there own shielding. Are the large shielding and the 5 smaller shieldings common with each other? If not, would could I use all 15 pins independently? If they are then I would only have 10 separate wires right?

Thanks ahead of time, I’m not very hardware/wiring savvy.


#2

I recommend DB25 because it is much cheaper than DB15 (VGA standard).

Here’s a diagram I drew up for connecting 2 wireless PCBs together. You can use as a reference.

DB25’s are wired straight through and pin 1 is usually used as ground. I wouldn’t use shielding as ground, I would tie it together to an independent pin dedicated for ground (pin 1). Don’t know much about VGA (DB15) standard, I believe not all the wires in a DB15 have the same impedance rating (impedance important for high speed video transmission).


#3

I prefer DB-15 for the one I’ve done; power, ground, 4 directions, six play buttons and 3 control buttons. The nice part is that you can match the Neo-Geo pinout, so your stick will play on AES and consolized MVS’s with just an extension cable, and use can use Neo controllers with your interface boxes.


#4

assuming your into neogeo stuff. if not then it doesn’t make any difference.


#5

Ok, just ohm’d the VGA cable I chopped up and found that all the shielding is in fact common. I also did notice that some wires had different thicknesses so VGA is a no-go.

faux123, Awesome! Looks like I’ll be using DB-25. Where do you get all of your DB-25 parts? The local radioshack didn’t have alot of stuff. Also, I’d like some more info on that selector switch, that would be bad-asss!

I’m trying to put 2 PCB’s in one box and having a selector switch saves me from having two DB female ports!

Thanks


#6

Check out MONOPRICE.COM. Best place on the net to get affordable HIGH QUALITY STANDARD cables period.

You will find the DB25 A/B switch on monoprice.com. It’s cheap around $8.

Good luck with you mod, post some pictures when you are done with it.

PS: My method is to connect a common ground PCB to a NON-COMMON ground PCB, so wiring is a bit more difficult. If both of your PCBs are common ground, you don’t need to use my method. You can search this forum for dual PCB mods or you can check out my site where I have posted a few tutorials for dual PCB mods.


#7

has anyone taken apart a db-25 selector and integrated it into a stick? Size might be an issue, would be cool though.


#8

Faux123, of course. Good ol’ monoprice.

HMMMM, do you think two PCB’s could fit inside the a/b db25 selector? If you bought one, whats the dimensions?


#9

Yeah, I was planning on using two common ground PCB’s but the stick I’m building is so slim that I may not even be able to fit a madcatz arcade stick PCB into it. Since I was gonna go with an independent PCB stick, I figured, “might as well make it multiple PCB’s”

Now you have me thinking… I think I’ll just use a DB-25 to connect the stick to the project box and have two common ground PCB’s joined. Time to look at those write-ups!


#10

Yeah… Is there any slim way to switch between two db-15 or db 25 cables? That box on monoprice is waaay too huge to fit in my stick case.


#11

i got a switch that has slots for 4 pcb. im loving it but to make room you can take the top off the switch box and it makes more room but for horis/jap sticks you might have to take it all out.good luck with that


#12

I read somewhere else in SRK that you can take all of the guts out of the a/b selector and mount it into your box.

BTW, just ordered some DB-25 cables today from monoprice


#13

Thejapino - Don’t get confused and only think there is only one type of DB15 connector, there is the VGA type which has 3 rows of 5 pins. There is also the one that Toodles is talking about which has 2 rows, one with 8 pins and the other 7 pins. Kinda like a DB25, but smaller.

You can then use any 15 core wire and solder your own plugs on the end.


#14

I plan on trying this soon.


#15

Ok, I ordered a molded m/f db-25 3ft thinking I could just cut it extra long on the male end. I was gonna wire the long male piece to the terminal strip in my stick and wire the short female end to the pcb in the enclosure. I hope I got the right kind.

Dreamcazman, I see what your saying. You build your own db-25 using some 15-strand wire and db ports. That’s cool


#16

nice, let us know how it goes.


#17

My switchbox was on the porch when I got home from school last night, so I eagerly opened it up and pulled out the multimeter to make sure it was straight through for all pins (I know some of them only send 14 pins through). To my joy, it was straight through. Well, it was 24 pins straight through (the 25th pin was a shared ground), but I’ll take it. In my pinout the 25th pin is for the home button, but since only the 360 and PS3 use a home button, I only had to move that pin on those two project boxes. I snipped off the shared ground wires.

I opened it up to see if it’d be possible to gut it and put it in my stick, and happily saw that it was. The selector knob is part of what looks like a turbine that has columns of three wires coming off of it all the way around. The wires are all going off to three different female DB25 connectors (one for the input, and the other two for the A/B connectors), and the turbine/knob and connectors can all easily be removed from the box. I took my stick’s signal/joystick wires, removed them from the barrier strip, and then clipped off the input DB25’s wires, one at a time, and spliced to the stick’s wires to match my pinout. When that was done, I spliced the B connector’s wires to lengthen them (they’re fairly short out of the box) and screwed it into my stick as the project box port. Today I’m going to send the A connector’s wires to a terminal strip, which will feed the internal PCBs.

I’ll take pictures as soon as I can and post them in the project box thread, but to answer your question, yes, you can do this. Here’s the exact box I ordered (it came to $13 with shipping and arrived about a week after I ordered it):

http://cablewebstore.com/DB25-Female-AB-2-Way-Switch/M/B000I9B2K0.htm