Side Projects: "mini" SLG & CGA->VGA converter

[yotsuya]

Just let me know when you're ready to take my money, CM! 

[CraftyMech]

Thanks Nephasth for posting up pictures of the 60-in-1 + mini-SLG!

The 60-in-1 puts out 640x480, which is perfect for the mini-SLG to work with. I have tested as well with the GBS-8200 CGA->VGA converter and the SLG worked great. I tried it out using a Namco Pacman/Galaga board.

As for the quality of the GBS-8200 itself, well that is another story I'm making progress though on my own CGA->VGA converter, and will be building scanline generation into the board, toggled on/off through an on-screen settings menu.

Just let me know when you're ready to take my money, CM!

Soon! Today I spent some quality time laying out the pcb, and fitting a large batch on a 7"x7" panel (50 units per board). I'll be putting the order through tomorrow, and with luck I'll get the boards back right before Christmas. My component/connector orders are also starting to come in, so I should have everything I need to start building the production units before New Years, and that puts me on track to start selling the first week of January. I'll keep everyone posted with some pics of all the parts piles once they arrive.

[Le Chuck]

I received my unit for testing earlier this week but wasn't able to do any testing until this evening.  This is an impressive little tool.  The integration is pretty much seamless.  My unit was missing the screw posts to secure the adapter to the monitor but being a test unit this isn't an issue.  Bottom line, it works and works well. 

Monitor used for this test: M170EN05 LCD, 17" AUO SXGA Max Resolution 1280x1024
Resolution used in this test:  480x640
MAME was paused for pics, shading on pause is 10%.

 
Galaga left to right (or top to bottom depending on which device you're reading the forums on) we've got no scan gen, scan gen red full up, scan gen middle, scan gen red full down. 


Same deal, no scan, red up, half, red down


I really didn't like the green too much so I turned the red full up and left it, just looked "more right" to my eye but YMMV.  The pot isn't a bad idea and I do notice a huge difference but I think that if you just went with a strong red and ditched the pot I wouldn't mind at all.  Dodonpachi shown without and with.  The scan gen really takes the edge off and gives the bullets a nice warm glow rather than being little pink squares. 

 
I played around with some horizontal games as well.  It does take the edge off and adds a richness to the background.  This is a great project and is heading in the right direction.  Crafty, you've got a real winner here.  I'll get it tried out on some other platforms but for right now I'm just having a blast playing and almost immediately forget it's there until I disconnect it and then I immediately miss it.

One thing that I did notice right away, my MALA skin looks like hot garbage with scan lines.  This is not an issue with the scan gen at all, just a result of designing the art based on how it would look on the stock monitor.  If you have an eye for that kind of thing and are building with one of these in mind you're going to want to design your layouts/skins/whatever to capitalize on the new presentation you'll be getting out of the monitor with this scan gen.  Makes me want build a dedicated vert cab.

[CraftyMech]

Thanks Le Chuck for posting up these photos!

I've been thinking about the trim pot and I agree with you that I think using a fixed resistor to give that setting a balance that is biased to Red would be a good compromise. The part is actually the most expensive component, and it is a bit of a pain to get it to fit in the plastic case and get the case to fit together right.

So although I'm one of those people that loves tinkering with adjustments to get exactly what I want visually, I think that by removing the pot the unit becomes 100% self contained, and truly plug & play, which is also a nice feature. Color balance can always be adjusted using the monitor controls as well.

One trick you can use with Mame skins, or other emulator menus is to run them at 800x600, or 1200x1024. Those are +vsync modes, so the mini SLG will just pass the signal through without adding scanlines.

Sorry I forgot to include the screw posts! The shells came with a set for each end but because I was plugging and unplugging the adapter so much during my testing I never installed them in the prototypes.

[Eldritch1969]

Hi,
Added a link to your project in the Scanlines Generators topic at Bartopmania.com.

Keep up the good work, CraftyMech

[CraftyMech]

Thanks Eldritch, I'll have to take a look at bartopmainia.com

Today I replaced the trimpot with a fixed resistor chosen to create a nice balance for the intensity of the RGB scanlines. I like how the result looks for the games I've tested. I used a Namco MsPacman/Galaga board, and my 60-in-1. More pictures to follow, but I think I've arrived at the final design! Removing the pot saves me $ and assembly time, and will allow me to sell the mini SLG at $15 like I've mentioned before. I like how the design is now a true plug-and-play adapter, just plug it up between your monitor and video source, and you have scanlines

Ms.Pacman (60-in-1 board) & mini SLG on a LCD (640x480):


Congo Bongo (60-in-1 board) & mini SLG + GBS-8200 CGA->VGA converter on a CRT (640x480):


Fatal Fury 2 (Neo Geo MVS board) & mini SLG + GBS-8200 on an LCD (640x480):


Fatal Fury 2 & mini SLG + GBS-8200 on a CRT (640x480):


1943 Kai (60-in-1 board) +mini SLG on a CRT (640x480):

[Nephasth]

Looks great!

[yotsuya]

Can't wait! Definitely in for three!

[emphatic]

Looks great!

It does indeed!

[CraftyMech]

Today I received an early Christmas present, the PCBs I ordered for mini SLG production!

To keep the per board fabrication cost low, I squeezed 50 copies of the design onto a 7" x 7" panel. I had to buy 4 boards however to qualify for the discount package, so lets just say I won't run out of stock for quite awhile

I scored and separated a row of boards tonight, and built and tested my first production unit. Worked like a charm!

The first picture below is one of the 7x7 panels, and the second picture is of mini SLG #1 in a black case. I will have two colors available for the plastic shell: beige & black. I also have a smaller quantity of the metalized plastic shell on the right.

I'll get a price list for single and multiple discounts posted this weekend, and I'll be ready to start building and shipping out units late next week!

[sharpfork]

If I order one, can we schedule a 1up or 2up delivery?

[CraftyMech]

Sounds like a plan, I have not been to a good arcade in forever. And I will accept payment in the form of beer

[Nephasth]

200 mini-SLGs!

[Eldritch1969]

Could I order two of these, please ?

[RigoHoward]

Today I replaced the trimpot with a fixed resistor chosen to create a nice balance for the intensity of the RGB scanlines.

Just wow! it's impressive!

I really respect your work and i want to thank youre sharing the schematic with all of us

I got one question (trying to do a mini SLG by myself), i can figure out what kind of resistor do you use to balance the intensity scanlines neither betwen wich pins it's placed. Can you give me a hint?

Thank you in advance!

[CraftyMech]

Hey Rigo,

In the schematic, the Red signal line is connected to the 100 ohm R4 resistor, and is connected to pin 5 of the IC. The blue signal line is connected to the 1K ohm R3 resistor, and is connected to pin 6. Both resistors are the common carbon film type, 1/4 watt.

[CraftyMech]

Could I order two of these, please ?

You bet Eldritch! I'm working this afternoon on figuring out the shipping cost to Europe. The mini is very light weight, so the shipping should be quite reasonable. I'll send you a PM once I have the numbers worked out.

[yotsuya]

Yay! 

[CraftyMech]

I started this project because I wanted inexpensive scanlines for my bartop build. Once I realized the design would be simple and very compact, I decided to offer the mini for sale because I believe an SLG is a must for retro gaming on VGA displays. My margin on each unit is low, so I'm not going to get rich selling these. If I can sell enough units to cover my investment in parts & time, plus a little pocket change, I'll be happy

The price list + shipping costs are below, just send me a PM with your order & email address and I will send you a PayPal invoice (for the time being, I will only be accepting PayPal for payment). I will start shipping orders next Friday!

mini SLG - $15 USD + shipping

Shipping: $3 USA, $4 Canada, $9 Europe (other destinations may cost more/less)


Deals For multiple units (US/Canada shipping included,  +$6 Europe):

"Duo" - 2 mini SLGs for $30 (save $3)

"Trio" - 3 mini SLGs for $42 (save $6)

If you are interested in more than 3 units just let me know in a PM and we can work out a deal.

Color choices for the plastic shell are beige & black. I have a limited quantity of shiny metalized plastic shells for $2 extra per unit (see photo a few posts back).

If for any reason you are not satisfied, I'll accept a return if you send a PM within two weeks of delivery (for the entire order, no partial returns). If you pay for return postage, I'll refund your entire purchase price (including original shipping costs) once I receive the unit(s) back.

If you have any questions, just ask. 

Scanlines for everyone!

[RigoHoward]

Hey Rigo,

In the schematic, the Red signal line is connected to the 100 ohm R4 resistor, and is connected to pin 5 of the IC. The blue signal line is connected to the 1K ohm R3 resistor, and is connected to pin 6. Both resistors are the common carbon film type, 1/4 watt.

Wow that was very detailed, many thanks!

Actually the problem was i was looking your old schematic..

I didnt realize that you updated the image

[bootsector]

Great work on making this a very accessible and affordable piece of hardware!

But what I like most is that you kept the open hardware spirit by making available the schematics.

You, Sir, got all my respect!

Cheers,

bootsector

Sent from my Nexus One using Tapatalk 2

[CraftyMech]

Wow that was very detailed, many thanks!

Actually the problem was i was looking your old schematic:

No problem Rigo! Although to avoid confusion, can you remove the old schematic from your post? Thanks!

Great work on making this a very accessible and affordable piece of hardware!

But what I like most is that you kept the open hardware spirit by making available the schematics.

You, Sir, got all my respect!

Thanks Bootsector! The projects that yourself and Toodles developed (RetroVGA & T-SLG respectively) over at the shoryuken.com forum inspired me to design the mini SLG. So you deserve credit for leading the way!

[RigoHoward]

Wow that was very detailed, many thanks!

Actually the problem was i was looking your old schematic:

No problem Rigo! Although to avoid confusion, can you remove the old schematic from your post? Thanks!

Fixed!

Thanks again, sadly i suck with this kinjd of projects , i already do all the wiring use the resistors and doesnt work for me

I check my soldering twice and even measure continuity using a multimeter but not luck yet

edit: i got video signal now after disconnecting HDMI cable (my bad...), but i dont get any scanlines i just have a ghostly image :S



BTW, how much it cost shipping two of your mini SLG to Chile?

[yotsuya]

Payment sent for 3! Thanks again!

[CraftyMech]

edit: i got video signal now after disconnecting HDMI cable (my bad...), but i dont get any scanlines i just have a ghostly image :S

It sounds like the output pins on the 74 IC are being held low. Double check that pins 2 & 6 are tied together, as well as pins 8 & 12. Those connections cause the Flip Flop to toggle with every vertical line. Also double check that vsync is connected to pin 1 & 13, and the HSync line is connected to pin 3. The Flip Flop won't toggle correctly without those connections either.

And shipping to Chile would be $9 USD, so just send me a PM with your email if you decide to order, I will start shipping next Friday

[Yvan256]

Not sure if it has been mentioned or asked, but what about offering your mini-SLG in kit form or even PCB only?

[CraftyMech]

Not sure if it has been mentioned or asked, but what about offering your mini-SLG in kit form or even PCB only?

My margin is low enough that there is not really an incentive for me to sell them as a kit. There are also a number of connections that have to be made between the VGA connectors and the pcb, so I can imagine a lot of troubleshooting on my end helping diagnose mistakes in wiring.

[Almighty]

Hello,

Looks awesome and let me know when they are ready
I really like to try one by myself for my new bartop build soon with a 60-1 pcb board.

Cheers

[CraftyMech]

Hey Almighty,

The mini SLG is ready to ship! A couple posts back is the price list, and also here in the buy/sell/trade forum: http://forum.arcadecontrols.com/index.php/topic,129344.0.html

PS - The mini SLG works great for 60-in-1 boards, I have one myself and used that board as my test system quite a bit while developing the design.

Just send me a PM with your email and order, and I'll send you a PayPal invoice.

[Almighty]

hello CraftyMech,

send you a pm for one mini slg

cheers!

[BadMouth]

I have a few oddball questions. 

Would it be possible to make a simple circuit that could turn the scanlines on and off on the fly (without bypassing the whole thing)?

What happens when it gets a widescreen resolution like 1280x720 passed to it?

[griffindodd]

PM sent, this will be the perfect addition to my little bartop cocktail.

[CraftyMech]

I have a few oddball questions. 

Would it be possible to make a simple circuit that could turn the scanlines on and off on the fly (without bypassing the whole thing)?

What happens when it gets a widescreen resolution like 1280x720 passed to it?

I was originally planning an on/off switch, but decided to not include one so I could keep the parts cost low & shave some time off of assembly. It is also a tight fit for the circuit board inside the shell, and it would be challenging to consistently mount a switch so that the case would snap close correctly.

For resolutions other than 640x480 or 1024x768, if the mini SLG is not compatible (the device requires a -vsync signal to work properly) then the screen will display normally without scanlines.

[ckong]

I got mine today. They are so tiny and sweet 



I suppose that they are meant to come without the screws?

[CraftyMech]

Hey CKong, great that your package arrived! Let me know how they work out for your setups.

The plastic cases I am using did come with screws, but they are tough to work with without a tiny screwdriver (not thumbscrews).  The cases were meant for VGA gender changers, so they were also just two sets of screws, rather then screws for one side, and posts for the other. The final straw was that they screws had to be in place when I snapped the plastic case shut, they have a lip on them that keeps them in place, but also prevents installing them once the case is shut. So I decided it was more trouble then it was worth for myself when building the units, and for the user because they were awkwardly small, and not hand adjustable.

[sharpfork]

I decided it was more trouble then it was worth for myself when building the units, and for the user because they were awkwardly small, and not hand adjustable.

Sounds reasonable.

[PL1]

CraftyMech -- For those that might want to find thumbscrews, what is the manufacturer/part number for the case you used?


Scott

[CraftyMech]

The screw holes are actually not threaded, so to install thumbscrews would require opening the case, and that is very tricky to do without damaging it. I've thought about sourcing a better case down the line if the unit continues to sell.

On a different subject, work continues on my CGA->VGA conversion board. I've been making good progress and have been able to drive a fairly stable image off a Neo Go MVS board, although more tweaking of the signal timing is needed. Once I have a nice conversion to demonstrate, I'll post up a YouTube video link of the converter in action.

The ADC module is still fairly primitive and just for prototyping, with 2bits per channel (6bit color). That works great for Pacman, but not so much for Neo Geo titles running on 16bit color. So I am experimenting with an 8bit ADC chip that if used one per channel would give a color depth of 24bits. The downside is it is SMD, so prototyping is a pain and requires soldering the chip to a small pcb that has through-hole pins and will plug into a breadboard. That is one bummer about the SMD revolution, a lot highly specalized integrated circuits, like ADC modules, are not available in DIP packages anymore. The ADCs that are available in DIPs tend to be under < 5mhz, which is too slow even for the 6-7 MHz pixel clocks of CGA "standard resolution" hardware.

[Yvan256]

Maybe not a good idea for the final versions, but it could help with prototyping...
https://www.sparkfun.com/search/results?term=soic+dip+adapter&what=products

[Le Chuck]

I'm using wee zip ties through the thumb screw holes to secure to my monitor and cable in the absence of thumb screws.  Seems to be working well but if I need to take it off for any reason I have to use a pair of snips.  Very secure.