MVS-99-6 - Project on hold until further notice (2014-03-10)

[Ryglore]

Excellent! Can't wait to see it in place and working!

[Yvan256]

Awesome, absolutely fantastic work. I have been trying to find a solution for MVS credit LED's for a year now.

Do you mean a real MVS cab? I don't want to disappoint you but my final board won't have the same pinout as the original MVS-LED boards... nor will it provide exactly the same functions. I don't want to create a credit display board that goes against the spirit of MAME, so it's not going to be complete enough to be used in a commercial setting.

The way it's going to work is "increase credit total by one when token is inserted, decrease credit total by one when player start button is pressed while at the same time send the player1 button command to the computer". The board won't care if MAME is started or not, nor will it be able to carry over credits when switching games. Just so it doesn't go all weird with the credit count I'll probably reset it to zero when I start a new game in MAME (via a parallel port pin).

I hope my explanation makes sense.

Real enough that it seems to work like a real one when in a game, but fake enough so that it can't be used in commercial settings. 

[jtslade]

No sorry I should of been more detailed. I realize that it won't interface with a real mvs LED. I was wanting to go toward the PIC controller route as well. Maybe use the LED's from a real board and de-solder them.

It's just good to have someone make so much progress on this front.

Keep posting the pics of your terrific work!

[Yvan256]

Once again, not much of an update, but it's some of the last few wood pieces to do on the cab...




The angled back bottom and the vertical hinged back panels are now in place! And so are the marquee and speakers!




Another shot from the side to better appreciate the MVS shape of the cab.




Eight screws currently hold the angled back bottom, once all parts are cut and fitted, it's also going to be glued using carpenter's glue. This panel isn't going anywhere.




I tried to take a close-up of the marquee and speakers, but the speakers panel is already painted black. And since all I currently have to take pictures  is a crappy webcam, we can't see much. Sorry about that. 

The top panel, which is going to be attached to the vertical hinged back panel, is almost ready too, I just need to cut it at an angle where it meets the top panel of the marquee holder. After that, monitor and CP supports and the rest is electronics, laminate/paint, artwork, etc. I'm almost done with the woodworking and I'm very happy with the results so far.   

[Ryglore]

Nice! Bet it feels good to take a break from the electronics and actually do a bit of the woodworking again! 

[jeffhlewis]

Real enough that it seems to work like a real one when in a game, but fake enough so that it can't be used in commercial settings. 

I've always thought it'd be awesome if Mame could emulate a 2 or 4 slot cab - i.e. the ability to specify 2-4 roms populating the slots on an MVS board. Like does the software or hardware control the credit counter between games?

[Yvan256]

I've always thought it'd be awesome if Mame could emulate a 2 or 4 slot cab - i.e. the ability to specify 2-4 roms populating the slots on an MVS board. Like does the software or hardware control the credit counter between games?

That would be nice indeed if MAME could emulate a two, four or six-slot cab, with the ability to output to external hardware to light up the mini-marquees.

As for the credits, you mean in my setup? There won't be any connection for the credit counter between games... The best I'll be able to do, I guess, is reset the credit counter between games. But other than that, the credit counter will show the number of token inserted and probably be connected to the "player start" button to decrease the counter.

[Bender]

Yvan

I was just looking for some black plastic corner guards to use for a marquee retainer and I rembered you were still looking
I found this and ordered some, though it might work for you too

[Yvan256]

I was just looking for some black plastic corner guards to use for a marquee retainer and I rembered you were still looking
I found this and ordered some, though it might work for you too

And it's 0.75" just like I need! Awesome, thanks for the info!

[Yvan256]

Okay, a lot has happened since the last time I wrote about MVS-99-6, one being that I dumped the Microchip PIC micro-controllers. Their weird bank system, their lack of registers, the accumulator (or whatever it's called) being the only place to do any real processing... it's too complex and was tired of messing around with all that cr*p.

So now I'm using the AVR chips from Atmel. I got a development kit and was able to not only start from scratch, but go beyond the point I was with the PIC in under four hours, and that includes rewiring the whole thing to the new chip.

I now have the counter that displays the number of credits AND it can be wired to a coin mech to count the coins. I'm still having small problems with the debouncing of the switch, I tried inserting 100 tokens and three or four times it registered two tokens instead of one.

The final plan is probably going to be:
1. insert coin
2. increase dual 7-segment display to show the new total credit
3. when the user presses [start], the total credit counts down by one credit if it's not zero

That way it's going to be a "real" MV-LED-look-alike in both look and function, up to a point. The [start] button doesn't know if MAME (or any other emulator) is ready to receive a [start] command, so the whole system is kind of "external" and completely independant of MAME/etc.

No photos or videos for now, I need to clean up the wiring first. I get hungry for spaghetti just looking at it. Besides, it's still the same LB-302VF dual 7-segment display, the only exciting part would be a video of me inserting a coin and showing the counter go up.


P.S.: I also ordered a big 0.56", red dual-digit display to make a prototype for life-size MVS MAME cab owners. I'll keep you informed on that, when the time comes it's going to be announced as a separate project ("MAME-MVS-LED" or something). The pcboard for that project will probably NOT fit a real MVS cab on purpose, as a first step to prevent usage in a commercial environment. Feel free to send me a private message if you are interested/opposed to this MAME-MVS-LED thing.

[Yvan256]

Ok, forget video, I can't shoot both the coin mech and the protoboard at the same time. So for now, here's a crappy photo montage of me inserting tokens into the coin door with a cropped 7-segment display pasted unto the cardboard next to the player start button.



Photos, from left to right:
1. Inserting a token
2. Token has been registered by the AVR and the credit display is now at " 1"
3. Inserting another token
4. Token has been registered by the AVR and the credit display is now at " 2"
5. "Player Start" button pressed twice, AVR has deducted two credits and now displays " 0"

Any further pressing of the "Player Start" button is useless since the AVR knows there is no available credit. The AVR will be connected to the "Player Start" button on the i-Pac, making the whole system act more like a real MVS cab (i.e. player start is useless unless there is available credits).

[Yvan256]

The ATtiny84 has 12 I/O pins, and I needed four for the coin and player start switches (input and output for both), so I was one pin short of controlling the two 7-segment digits. So with the help of a few users on the SparkFun forums I was able to save one I/O pin to control my dual 7-segments display. It may seem insignificant, but I already have ATtiny84 chips and since my space is limited I couldn't really go with a higher pin count chip (such as the ATtiny2313).

I added a transistor inverter, so bit 7 now controls the two digits instead of requiring on bit per digit. Since I don't use the decimal point, only one 8-bit port is required to control the 14 segments of the two digits.

The schematic below is a composite of two drawings I found on two different websites:
- http://www.kpsec.freeuk.com/trancirc.htm, "A transistor inverter (NOT gate)"
- http://www.picbasic.com/resources/articles/ledart.htm, "Figure 6"

[Yvan256]

I hit a small problem with the ATtiny84... I forgot to reserve the /RESET pin so that in-system-programming would still work. So I'm actually one pin short, even with the transistor trick I mentionned earlier.

So... long story short, I switched to the ATtiny861. The rewiring is already done and the circuit is working once again. And this time I have a working ISP header just in case I want to modify the code. Since the ATtiny861 has 16 I/O pins (minus one for /RESET) compared to the ATtiny84's 12 I/O pins (minus one for /RESET), I was also able to drop the 3rd transistor. I even have two I/O pins left in case I think of something else.

The C code compiles to 514 bytes, so yes I am wasting code space by using an ATtiny861 AVR instead of going for a cheaper ATtiny261. But since the price difference is only 26 cents, I said why not. You never know when you'll need more code space.


On another node, I was also finally able to get the LCD6610 working and can display bitmap graphics now. It's currently connected to the ATtiny84 (See? It will be used after all!) and displays a 132x46 mini-marquee of Rygar. I'll have to get the whole thing working with a 2MiB flash, DIP-8 IC since I've decided it would be easier to just ask the front-end to send a binary value through the parallel port (from 1 to 99, it is called MVS-99-6 after all), to tell the ATtiny84 which stored mini-marquee to display. If I ever decide to add more than 99 games I'll have to write the new mini-marquees into the small Flash IC, but 2 MiB is a very limited amount of storage space and I'm guessing I'll even have trouble storing 99 graphics, even accounting for the fact that non-Neo-Geo games have roughly 132x64 marquees at the most (ex: Rygar is 132x46).

[polaris]

fairplay man youre doing some incredible work here on the tiny details, great stuff. 

[Yvan256]

Attached are the two best pictures of the LCD I was able to take. In real life the display is very sharp and very bright. Disconnecting the LED backlight doesn't help as it only makes the whole thing completely black. People weren't kidding when they said "photos doesn't do it justice". I'm still wondering how they were able to take pictures at all. Maybe not using a crappy webcam would lead to better results.

Also attached is the picture the LCD is displaying in the first two photos (hint: no need to click on this one, it's displayed full-size already - 132x46 really is that small). The fourth photo is the new circuit of the credit display with the ATtiny861. That 6-wire flat cable on the right is connected to the ISP header which allows to reprogram the micro-controller in-circuit. To the right of that, out of the picture, are temporary buttons connected to the "coin mech" and "player start" inputs of the ATtiny861. Also missing are the two wires that will go out from the ATtiny861 to the i-PAC "credit" and "player 1 start" inputs.

[Yvan256]

MVS owners: I need your help!

If you have a Neo-Geo cabinet with a working MV-LED board I'd like you to take pictures of 6 credits, 7 credits and 9 credits being displayed. Also say if it's from a MV-LED or a MV-LED2 board (horizontal or vertical one).

The reason I'm asking for photos of the digits being displayed is because of the different ways of making the numbers 6, 7 and 9 on a 7-segment display. It's a small detail, but why bother making a credit display board if it doesn't show the same thing as a real MVS cabinet.  

[CheffoJeffo]

There are no serifs -- the numbers appear as in the lower picture.

[Yvan256]

There are no serifs -- the numbers appear as in the lower picture.

Great, it had to be the ugly ones. 

Oh well, if that's how the real MVS cabinets displayed credits, then that's how MVS-99-6 will display its credits too.

[Ryglore]

How goes the MVS-99-06?

[Yvan256]

How goes the MVS-99-06?

It's in standby for now, though I did make this about three months ago. I know, the top edge isn't cut properly, but I was in a rush when I made this.

The components are on one side and the 7-segment display is on the other side. This way the pcboard can be screwed flat into the MDF and I used the length of the pins of the 7-segment so that its top surface is flush with the other side of the MDF.

[emphatic]

  That looks great!

[Ryglore]

Awesome display. I envy your PCB building skills. 

[Yvan256]

Awesome display. I envy your PCB building skills. 

Actually the PCB was made by ExpressPCB (MiniBoardPro service).

[Ryglore]

Well in that case... they are awesome.

[WhereEaglesDare]

 

[Kman-Sweden]

Update?

[Yvan256]

No update to do since last time. No money and no time means the project is on standby.

[WhereEaglesDare]

  What is the foot print of your cabinet?  How wide and deep is the base of it?  How tall is it?

[Yvan256]

  What is the foot print of your cabinet?  How wide and deep is the base of it?  How tall is it?

The cabinet is 23.4 cm wide, 31.8 cm deep x 35.8 cm tall (9.21 x 12.52 x 14.09 inches), without the rubber feet and without the T-molding.

[WhereEaglesDare]

WOW, that IS tiny!  Im thinking about building a similar one.  but its going to be 25 inches high, because I dont have a MiniITX... its going to be a little less than double.  20 inches wide x 17 inches deep, and 25 inches tall.  Its going to be wider than the proportions allow, but I think it'll be manageable.

[Yvan256]

WOW, that IS tiny!  Im thinking about building a similar one.  but its going to be 25 inches high, because I dont have a MiniITX... its going to be a little less than double.  20 inches wide x 17 inches deep, and 25 inches tall.  Its going to be wider than the proportions allow, but I think it'll be manageable.

Similar one, as in another small Neo-Geo MVS cabinet? Can't wait to see that!

[WhereEaglesDare]

Well I just got back from Lowes with some wood, fresh new saw blades, and a new set of ear pro, got 4-5 hours left til dinner time so I should be able to get a good bit of cutting done today.

http://forum.arcadecontrols.com/index.php?topic=104764.0

[WhereEaglesDare]

WHat did you use to round off the front of the CP?  I read your mote about it and it does look scary, especially when you already have all the holes cut.



Any tips?

[Yvan256]

WHat did you use to round off the front of the CP?  I read your mote about it and it does look scary, especially when you already have all the holes cut.



Any tips?

I used my father's router table with a round corner bit. I was afraid the corner of my control panel would not hold, but there was no problem. Then again, I used metal brackets, screwed with pilot holes, and all panels glued with carpenter glue. If it had broken apart, it would have surprised me.

[WhereEaglesDare]

You are putting plexi over the CP, are your rounding off the edge of it?

[Yvan256]

You are putting plexi over the CP, are your rounding off the edge of it?

As you can see in reply #151, the original Neo-Geo MVS cabinets only had a flat plexi over their CP. It stops before the round corner.

Since I try to follow the original design as much as possible that's how mine is going to be too. And thanks to javeryh, I have 6 very small bolts to complete the effect. I'm not sure if I'm going to paint them black or not yet, but at least they're the right size for this miniature version of the cab.

Unless you actually meant rounding off the edges as in remove the sharp corner in the thickness, then I'm not sure. I can't remember if the originals were like that either. To keep things in scale, I'm going to use 1/16" plexi. I'm not sure it's worth rounding off the edges of such a thin material.

[Yvan256]

It's been a few months since the last update... Time flies.

The viewing angle of the LCD for the mini-marquees isn't good enough, not to mention that the backlight of the LCD makes it look more fake that it has to be. I know Neo-Geo mini-marquees were backlit, but it's a transparency lightning, they do not emit light themselves. There's also the aspect ratio of the current LCD (nearly square) which doesn't quite fit the Neo-Geo mini-marquees. And it's just a bit too small.

So I'm going to replace it with an OLED display. I was able to get 50$ from SparkFun's Free Day, so it means I was able to buy this 1.7" OLED module for much cheaper. Vertically, it's almost the perfect aspect ratio of mini-marquees, it's a bit bigger, it fits physically in the space I have and the built-in controller and microSD slot means displaying and adding new pictures will be much, much easier.

[Bender]

can't wait to see the New OLED

[Yvan256]

After reading the datasheet, I learned that:
- it doesn't support a file system (no FAT32, it uses direct block addressing... what's the point? Requires Windows software to load/convert the images, too)
- it doesn't support standard file formats (well, the Windows software does, but what's the point)
- you shouldn't display the same static image for "lengthy periods of time"... never mind that they don't even specify an actual recommended maximum time, it's a marquee!

I'll keep my current 128x128 LCD display. The ideal solution would be a color e-ink display. Maybe one day.

[Kman-Sweden]

How about placing the minimarquee behind a "smoked" screen? Maybe a piece of "DIY-Car-window-tint-kit" or something similar..?