rotating monitor methods

[edge]

csa3d -
I think they mean that when a user selected a horizontal or vertical game, the front end can send a signal to the LEDWiz (or similar hardware) to turn on/off the rotating motor.

As for relays.. I think whamoed (sp?) makes a little hardware relay that people have used to turn on/off their PCs/marquees/etc.  Maybe that is another option to automatically control the rotating engine?

[csa3d]

Edge:  Yes, this makes sense.  So everyone is talking about part 1 of 2 to achieve this.  Someone still needs to write the interface to the hardware, and that missing link belongs in the front end.  So currently, there is no "out of the box" solution to this as I understand it.  I suppose upon reading the first few posts, I got to thinking maybe there was and I was missing something.

Thanks!
-csa

[koz319]

I was going to take some pictures of the monitor setup in my cab this weekend, but I forgot I loaned out my camera.  I got the camera back today, I'll try to take some pics tonight.

I did find some old pics from when I was building the cab.  Unfortunately, they were taken with the worlds worst digital camera.  They also unfortunately dont show any of the electrical connections.  They do give a fair idea of how the monitor is mounted though.  If you look in pic mountcab5a.jpg,  you can barely make out the motor and belt used to turn the monitor.  (Motor drives a belt wrapped around the monitor 'cage' to turn it.)

The current command line util I use to control rotation can be called from a frontend before mame is launched to turn the monitor.  (FWIW, the mame recompile is pretty simple, this is actually what I use now.)  I do want to get away from having to modify mame to auto rotate though.  I'm about halfway done re-writing the cmd line prg to query mame for a games orientation and rotate as necessary.  The idea is to call this prg (instead of mame) with whatever parameters you normally pass mame. The prg queries mame, rotates as necessary, then launches mame passing the params.   

I'll post the pinouts/wiring I'm using, I just need to find my wiring diagram in my garage .   I'll also post the command line util if anyone is interested.

If you want to build your own controller,  see this link http://www.bobblick.com/techref/projects/hbridge/hbridge.html

This is the basic circuit I'm using, I just connected it to the parallel port and added limit switches.

I want to make two more of these for myself.  I took a look at what it would cost for the components and to get a few pcb's printed.  Looks like it's right  at 25$.  Thats for a complete PCB with components, terminal blocks for the motor supply in, power output, limit switch connections, as well as a db25 connector and a 25pin cable to connect to the pc.   If anyone else is interested, let me know ($25 is actual component cost, not interested in trying to profit here)

Anyway, here are some really bad pics.

Koz

[ahofle]

Not sure if this was mentioned, but how do you handle the bezel for a rotating monitor?  Would it just be a 'plus' shaped hole that partially shows the back of the cabinet?  Tinted plexi?  I also suppose it could also be done with two overlapping bezels.

[koz319]

Not sure if this was mentioned, but how do you handle the bezel for a rotating monitor?  Would it just be a 'plus' shaped hole that partially shows the back of the cabinet?  Tinted plexi?  I also suppose it could also be done with two overlapping bezels.

If you look at the pics attached to the previous post, you can sort of see one way of doing this.   Normal Happ bezel attached to monitor and trimmed.   Plexi masked and painted (in the plus shape you mentioned) to mask everyting else.  Looks decent IMHO.

Koz

[ahofle]

Ahh, I totally missed that.  Looks good! (I assume you painted the circular wooden piece around the monitor black as well?)

[koz319]

Ahh, I totally missed that.  Looks good! (I assume you painted the circular wooden piece around the monitor black as well?)

The wooden circle is completely cover by a standard Happ bezel, which is trimmed to the shape of the circle.  (So the circle is not painted) This bezel rotates with the monitor.

The painted plexi covers everything else. The Happ bezel shows through the 'plus' shaped window in the plexi.

Koz

[DaOld Man]

Any progress on making an interface to automatically rotate the monitor?
Im thinking of making a program that is launched by a frontend, such as GLaunch, that could look up a list of games, and turn on an output (printer or serial) to rotate the screen.
For example: run galaga88.
Program looks on a list of games for Galaga88, if found in list, read in desirable screen position, turn on appropriate output to turn screen.
If game is not on list, use a default setting.
My problem right now would be how to intercept the run game command from the front end.
Perhaps there is a frontend already out there that can do this?
This is just an idea in its infancy. Appreciate any input.

[telengard]

I built a rotating monitor in my cab (21 in. crt) - controlled through the parallel port.   The parallel port controls an h-bridge which controls the direction of motor rotation. (if one pin is high, rotate clockwise - if the other pin is high, rotate counter clockwise.) 
There are two limit switches - each switch is set up to interrupt the signal to the h-bridge to stop rotation, as well as set another pin on the parallel port so the pc can read when the limit is reached.  Another paralled port pin is attached to the monitors degauss circuit. 
I wrote a quick command line prg that you pass a few arguments to - which way to rotate, degauss at end of rotation or not, and a timeout in seconds, so the montitor will stop turning if there is a limit switch malfuntion.   You can use this from you desktop or call it from whatever to change the monitors orientation.

I also re-compiled mame to do this automatically based on the orientation of the game that's launched.

If any of this sounds like it might be helpful, let me know, and I'll pass on any info you may want.

Good luck!- I think the rotating monitor is awesome.

Koz

I'd be very interested in your patch to mame etc.  I have a rotating monitor and one of the few things left on my TODO list is to make it automatic.  I'm not sure if my computer has an LPT port though.   PCs don't seem to ship with them anymore which is a shame because they are *perfect* for a lot of stuff like this.  I'm porting and modifying an existing program to act as a 1541 disk drive over the parallel port.  Hopefully parallel port cards will continue to be available.

What method did you use for rotating?

EDIT: Didn't realize this was a grave diggin' thread.     

~telengard

[telengard]

Not sure if this was mentioned, but how do you handle the bezel for a rotating monitor?  Would it just be a 'plus' shaped hole that partially shows the back of the cabinet?  Tinted plexi?  I also suppose it could also be done with two overlapping bezels.

If you look at the pics attached to the previous post, you can sort of see one way of doing this.   Normal Happ bezel attached to monitor and trimmed.   Plexi masked and painted (in the plus shape you mentioned) to mask everyting else.  Looks decent IMHO.

Koz

I did the exact same thing pretty much, except I have a PC monitor and a foam-core bezel (soon to be D9500 and Happ bezel).  The glass bezel has the "plus" slightly smaller than the size of the bezel which also is trimmed so when rotating it, it doesn't catch on the cab.

~telengard

[DaOld Man]

Im not sure if you replying to my post or the one you quoted.
But I have not started on my rotatable monitor yet.
What method did you use? Any pictures or links?
The last motherboard I purchased a couple of years ago did have a printer port.
But all MB's now have USB, so it may be possible to use that as an I/O port to do what we want.

[telengard]

Im not sure if you replying to my post or the one you quoted.
But I have not started on my rotatable monitor yet.
What method did you use? Any pictures or links?
The last motherboard I purchased a couple of years ago did have a printer port.
But all MB's now have USB, so it may be possible to use that as an I/O port to do what we want.

Oops, sorry yeah I was responding to the ones I quoted, but I thought this was a new thread.  Who knows if those folks still hang out on the boards.

I haven't seen any USB -> LPT cables yet just USB -> Serial.  That's great they exist though.  Might have to look into that.  I did my rotating monitor pretty much exactly like Mr Salty.  If I could give one word of advice on his method that I've learned over the past few years is to try and cut as best of a circle as you can.  Any part that isn't uniform near where the monitor is parked will cause it to move slightly to the left/right which can be annoying if little things like that drive you crazy (like me).  I used a jigsaw to cut it and wish I had taken it somewhere to be done better.  I stink at woodworking.     

As for my project it's here, if you have any questions about rotating I may be able to help, except for with doing it automatically w/ hardware.  that's next on my list of things to do.

http://users.adelphia.net/~bsturk/mame.html

~telengard  (does my site show up in my sig???)

[DaOld Man]

Your site looks good. (The url does show up in your signature BTW)
Do you have details on how you hooked a motor to it?
Also, I was thinking of using metal instead of wood to mount the monitor to, and maybe use some type of bearings to support it, however, looks like the cabinet wheels worked good for you.
I was thinking of using USB as a serial port, not LPT. I am sure you can write to the USB to turn on an output card, however a printer port is much easier. I have done projects at work that uses the printer port for inputs and outputs. Its really not that hard. The output (one pin and a ground on the LPT port), could turn on a transistor, which would turn on a relay.
It would be neat if I could write a program that will recognize when a mame game starts, then look in a data file to see which way the screen needs to turn for that game.
Its just easier said than done.

[telengard]

Your site looks good. (The url does show up in your signature BTW)
Do you have details on how you hooked a motor to it?
Also, I was thinking of using metal instead of wood to mount the monitor to, and maybe use some type of bearings to support it, however, looks like the cabinet wheels worked good for you.
I was thinking of using USB as a serial port, not LPT. I am sure you can write to the USB to turn on an output card, however a printer port is much easier. I have done projects at work that uses the printer port for inputs and outputs. Its really not that hard. The output (one pin and a ground on the LPT port), could turn on a transistor, which would turn on a relay.
It would be neat if I could write a program that will recognize when a mame game starts, then look in a data file to see which way the screen needs to turn for that game.
Its just easier said than done.

Unfortunately I haven't hooked up a motor (yet).  I manual rotate by grabbing a cabinet knob I installed on the wooden circle.  I think you can see it in the screenshots on my site.  Making Mame do what you described wouldn't be too difficult (then again I'm a software developer and have hacked mame/mess) but the HW aspect is what has kept me from doing it.  I have minimal electronics design skills.

~telengard

[Jimbo]

I've been playing around in sketchup lately trying to design my cab.  I'm getting a 21" Hantarex Polo arcade monitor, and I want it rotate, so I've taken a few ideas from other projects on this site and come up with this (see pics below).  I've designed it to fit into a cab that's 28" wide, and the monitor is to be mounted at a 45% angle. The monitor unit can slide in from the back of the cab.

I haven't started building yet as the designs are still unfinished, but its getting there   Sketchup is great!

jimbo

[DaOld Man]

I like it. Hope you dont mind if I borrow some ideas from you.
What is sketchup? And where, pray tell, do I get it?

[RandyT]

Somehow this thread made its way past me in February, so my apologies for being so late to the discussion.

The LED-Wiz could indeed be used to control something like this.  I know AtomicFE allows for a user to tweak the LED-Wiz lighting on a per game basis, and others may as well.  One would need only to designate a particular output on the LED-Wiz as "Horizontal" and another as "Vertical".  Then tweak all of the control lighting definitions as necessary.

It could also be done with a small app that watches for the game title being played in MAME, searches through the game info file for whether it's a vertical or horizontal title, and then turns on the appropriate outputs.

The wiring would probably want to be such that a limit switch at the end of travel in both directions sends a signal to the software to kill the motor.  The LED-Wiz+GP would be a good solution as it has both Inputs and Outputs on one board.  Of course, a relay circuit with a means of reversing polarity on the DC gear motor would also be necessary.

RandyT

[danny_galaga]

ooh, that sounds great! and im already a fan of atomic as well. the rotation on mine is set up so that when the monitor reaches its limit, the microswitch cuts out and is set up for the opposite rotation. so signal-wise my particular set up only needs two different + signals. hmmm...

[Jimbo]

I like it. Hope you dont mind if I borrow some ideas from you.
What is sketchup? And where, pray tell, do I get it?

http://www.sketchup.com/

Its a 3D design program that's free, and easy to use.  I think its perfect for designing a cab.

[DaOld Man]

It could also be done with a small app that watches for the game title being played in MAME, searches through the game info file for whether it's a vertical or horizontal title, and then turns on the appropriate outputs.

The wiring would probably want to be such that a limit switch at the end of travel in both directions sends a signal to the software to kill the motor.  The LED-Wiz+GP would be a good solution as it has both Inputs and Outputs on one board.  Of course, a relay circuit with a means of reversing polarity on the DC gear motor would also be necessary.

RandyT

The reverse rotation would be very simple. Using two relays rated for the current of the motor, one supplying current in one polarity to the motor, the other supplying current in reverse direction. A end of travel limit (one for each direction) could turn the appropriate relay off. One output is all that would be needed. Output on, turn monitor one way, output off, turn it the other way.
I just need a software app that can tell when a mame game is called to start, and identify the game. A list could be made with each game displaying if it needs the output turned on.
Default for non listed games would be output turned off.

[DaOld Man]

Oh, sorry I forgot to say this on last post:
Thanks Jimbo for the link. I will check it out tonight, at work right now..