Serial Vs. VGA cable

[Jeremy airjer W]

Are they the same? I have two dance dance revolution interfaces that have broken pins in the cable ends. They look like serial cables. I found some VGA cables that look the same. Soldered them in and have no function control. I'm thinking they are two different things?

[Whoaru99]

No, they're not the same.

A serial cable generally is a DE-9 connector with nine pins. VGA typically uses a DE-15 connector with 15 pins.

Although, evidently it's not impossible to have a 9-pin video connector such as an older CGA or EGA video setup.

Generally, I'd expect a video cable to be a straight through pinout, but communication cables may not be...and that's likely the issue.

[Jeremy airjer W]

15 pins

[Jim Almquist]

Pin out for a VGA cable

Pin 1 RED Red video

Pin 2 GREEN Green video

Pin 3 BLUE Blue video

Pin 4 N/C Not connected

Pin 5 GND Ground (HSync)

Pin 6 RED_RTN Red return

Pin 7 GREEN_RTN Green return

Pin 8 BLUE_RTN Blue return

Pin 9 SENSE +5 V DC from gfx adapter

Pin 10 GND Ground (VSync, DDC)

Pin 11 N/C Not connected

Pin 12 SDA I²C data

Pin 13 HSync Horizontal sync

Pin 14 VSync Vertical sync

Pin 15 SCL I²C clock

Pin outs for a DB15 cable with the direction of the pins

Pin 1,8.15 system ground

Pin 11 carrier detect in

Pin 13 Receive in

Pin 12 transmit out

Pin 10 Data Terminal Ready out

Pin 3 Data Set Ready in

Pin 4 Ready to send out

Pin 5 Clear to send in

Pin 6 Ring indicate in

On a DB15 not all pins are used and when they reach the other end they will not be on the same pin. Pin 13 will be 12 at the other end and the same thing with pins 4 and 5. I hope this helps even though it will not fix your problem.

[Whoaru99]

It's somewhat possible, unfortunately, that it could be a non-standard/proprietary pinout too.

Best I can think of is to break out mulitmeter and use some small pins to see if you can probe the broken and unbroken pins to try to map out the cable.

[Jeremy airjer W]

Now it think where getting somewhere. If I understand what your saying the pins at one end could be wired to different pins on the other ends? This cable has male ends on both ends. Would this hold true for this type of cable? The other thing is there is one pin missing on the new cable but it has all the wires of the old cable had plus 3.

I guess I'll start ohm checking and see if the missing pin is the problem or the cable wiring is the problem.

Thanks so far for the help.

[LMITOUT]

Yep, some wires will "cross over", so the wire on end "A" in location #1, may end up on location #2 on end "B". Wire #1 on end "B" will then end up at location #2 on end "A". This is a typical transmit/receive pair.

If you can figure out the wiring from the old cable you can easily build a replacement with a soldering iron and parts online. We build them at work on occasion to fit our needs.

We have cables that are used for specific equipment and if you didn't know any better (or they weren't labeled) they would all look like a typical serial cable as they have the standard 9-pin connector. However, each device or manufacturer likes to put their own spin on the communications and they have their own special pin-outs. Makes it a PITA because you need to have multiple cables depending on what you're connecting to.

[LMITOUT]

If all else fails it looks like a replacement cable is about $10.

[Jeremy airjer W]

Know I get it. The one pin that is missing on the knew cable is the pin for the black wire on the old cable. I should have paid more attention when I picked up the new cable but who would think there would be a missing pin?

[Sandmannd]

Looks like you got it.

What happened Jer, you get a little crazy on the dance board this weekend?

[Jeremy airjer W]

No, they have four of the industrial strength units for the program my wife works for. They loaned them out to an event and three of the cables came back broken. I figured for $5 I'd try to fix them but it look like these must be some sort of custom cable. Unless I can find a 15 pin with all the pins and all the wires. I snipped another one I had laying around and there is definitely not enough wires but all the pins are there?????

It uses twelve wires.

[Jeremy airjer W]

This is what it is. The broken pin is one of the pins used in the interface so it has to have one. The pin thats missing in the VGA cable is also needed. Anyone have any experience with RGB cable? This is what it looks like.

[Wade Joseph]

Looks to me like an RS232 connection. You can but replacement plugs and assemble them yourself.