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Rotating monitor construction *Project finished*

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DaOld Man:
Thanks, I suppose you are right about the heat sink. But ambient temperature was 68 F at the time I took the temps. Im sure the temp inside the cabinet in summertime will be higher.

Update:
Here is the promised picture of my new (old) motor.
Notice the knob on the end of the motor. Might be handy if something fails, turn knob until monitor is straight. I might be willing to part with one of these motors, but I wont decide which one to keep until I build the monitor support system.
I will post it then, so if you need a motor, keep an eye out.
Second picture is a printer cable I picked up at a yard sale for 50 cents.
I plan to cut the printer end off. The end I am holding will plug into the computer printer port.

DaOld Man:
Ok, I cut the printer plug off the cable and stripped back the outer jacket. (See first pic).
I then separated the wires, and trimmed each.
I then used my multimeter to "ohm" out each wire. (Second pic)
I wrapped a wire around the black probe, then touched the red lead to each pin of the plug on the other end of the cable. When I had zero resistance, I wrote the wire color down, and the pin number that the wire attaches to. I dont know if there is a standard color scheme for all printer cables. (I couldnt find one on the web). So I suggest you use this same method to identify which wire goes to which pin. The pins are numbered inside the plug (You might need a magnifying glass).
There are 13 pins on top, numbered 1 to 13.
There are 12 pins on the bottom, numbered 14 to 25. Pin 14 is the first in the bottom row, and is located below pins 1 and 2.
This cord has a shield (bare wire). This wire connects to the plug's metal case.
It will not be used in my application. One wire (Black w/ white stripe) connects to pins 18 thru 25.
These pins are all grounds, and need to be connected together to protect against noise, this cable will save me a little work, since it already has the grounds connected together.

DaOld Man:
I rigged up a test station. (First two photos)
I ran Koz319s program from command prompt and the leds lit as expected.
I could not wire the inputs as Koz319 did his. The inputs on my computer seem to float high, which means they give a high signal when connected to nothing. So I had to "tie" them to ground to bring them down to low.
I connected the inputs to ground through a 470 ohm resistor.
I then had a 330 ohm resistor tied to the output. I touched the 330 ohm resistor to the input to simulate a switch closing.
This works great.
I tried entering a call to Koz319s "rotate.exe" program in GLaunch.
In mame.cfg, I entered a pre command of "C:\(path to the rotate program)\rotate r 10"
Then I entered a post command of "C:\(path to the rotate program)\rotate l 10"
When I ran a game, the red led came on for 10 seconds, or until I touched the resistor leads together (simulating a switch closing). The red led went off and the game started.
It did the same thing for the green led when I quit the game.
This will work great if all your games in mame.cfg are rotated, I am working on a small program that will recognize which game needs to be turned. I think Koz319 is too.
The third picture is the diagram of my test rig.
Dont let this overwhelm you. It is really pretty simple.
Note about my test rig: I use an old Heathkit breadboard I got off ebay. These things are very handy. Radio shack sells small boards without power supplies that are pretty reasonable in price. I recommend you get one, if you want to get into electronics as a hobby. The parts on the right side of the board is a separate experiment Im doing with the nutchip.
Saint: Let me know if I am posting to much stuff on here. I dont want to use up more than my share of your server space.

DaOld Man:
Just a quick link to an informative site about printer cables and plugs.
It even tells how to make your own.
But the wire color chart does not match the colors in my cable, so I would not go by that if you are hacking an old printer cable like I did. Use the method I used with an ohmmeter (multimeter), or use an led and battery to identify which wire is attached to which pin.

http://www.geocities.com/keinhong/nfpt/ecp_cable.html

javeryh:
Awesome work DaOld Man!  I wish I could follow in your footsteps... I'm going to give the whole rotating monitor a shot on my next cab but It might take me forever to figure all this stuff out!   I only want to implement it if the rotation is automatic based on the game selected - I've got a lot of reading/learning to do!  :cheers:

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