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Thursday, August 16, 2012

Armed Police Batrider artwork

Received the following awesome Raizing artwork, thanks to Bay!

Wednesday, July 04, 2012

CGA2VGA scaler for arcade PCBs

UPDATE (03/01/15) There have been a lot of breakthroughs in hacking these Gbones upscalers via Raspberry Pi and I2C connection.   Details can be found on the shmups forum thread located here.

I made a very interesting discovery with the CGA2VGA scaler that came in my Red Storm cabinet.  The scaler looks like the generic/OEM version we've all seen on eBay for ~$35, except even cheaper since they removed all the components except for RGB input and VGA output.  But the big difference is the one that came in my cab can successfully scale PCBs of various refresh rates, like the very difficult Seibu 55hz games!

Here is a visual comparison.  The Gonbes GBS-8220 in on the left, and the Red Storm generic is on the right.

(click picture for hires pic)

Comparing both side by side in a similar setup, the menus are exactly the same, except the red storm version allowed for a wider range of values to be set for horizontal and vertical settings.  Looking closely at the both boards, the GBS-8220 has a 2011.08.16 V30 silkscreened on it, while the stickers on the red storm version looks like it's firmware was updated in February of 2012.

So I'm hoping someone can help me figure out how to dump the firmware of the red storm version and see if I can successfully upgrade the GBS-8220 firmware.  I see there are two sets of 4 pin "upgrade" connectors on the right side, although it looks like some were removed.  There is also a 2 pin connector directly under these which I assume may be a selectable "write" jumper?

Monday, April 09, 2012


Assault is an amazingly fun (and difficult) overhead tank arcade game that has a distinctive style all its own.  The original vertical cabinet is pretty unique being noticeably thinner, with twin stick controls, making it a rare find outside of its native environment.

I wouldn't hesitate picking up an Assault cabinet if one were to pop up locally, but given the opportunity to buy the PCB alone (a Namco System 2 board), I considered it a challenge to see how it would play in one of my vertical candy cabinets.
Being a fan of dual playing certain vertical shmups, I'm rather comfortable using both player sticks simultaneously while pressing A and/or B buttons.  This got me thinking that playing Assault on a typical candy control panel shouldn't be that difficult given proper re-wiring of the controls.
Rather than re-wiring actual connectors under one of my control panels, I just created a little adapter to remap the right stick controls over to the Player 2 inputs, and then mapped the A button to both sides.  Since the original cabinet used 4-way sticks, I did have to adjust my Sanwa JLF-8YT restrictors to 4-way, which honestly I didn't even know was possible until I looked into it.
What we have left is the following control setup, which is probably faster/easier for making small adjustments in aiming than using the original grip joysticks.  It didn't take long to get used to this setup, where I primarily used P2's shoot button with my right pinky. Pulling the sticks apart to perform the bomb shot seemed almost too easy, in fact I kept accidentally doing this while trying to perform quick horizontal roll dodges...which is just a matter of me getting more practice with the game.

Overall I'm pretty happy with how this plays, but again, I'd prefer the overall vibe and feel of an original cabinet if one were to be found locally.

Sunday, April 01, 2012

Red Storm 32" LCD arcade cabinet

I've been saving up for over a year now to get an LCD cabinet, and sold one of my Astro City's to make room in my garage.  The wait paid off last week when I was able to take home a new Red Storm 32" LCD cabinet.

This is a sister to the Black Storm 32" LCD cab (as seen on arcadeotaku back in September).  They are made in China and based on the New Delta 32 design by Riverservice (although not a direct copy).  Unlike the New Delta 32, there is no slick LCD rotate mechanism, but its fairly easy to unscrew the four bolts holding the LCD onto the frame to remove and rotate manually.  The LCD itself weighs about 50 pounds, so a single person can rotate it without a problem. 
Visually, the Red Storm differs from the Black version by the color of the control panel and monitor although the rest of the cab has the same red accents.  Personally, I think the Red Storm looks better, especially with the red light up panel.

The LCD on the Red Storm also differs from the Black Storm, with a host of inputs including VGA, HDMI, Component, and S-Video (Black version only has VGA and DVI).  Inputs are located on the side of the LCD rather than the bottom like the Black version.  This however presents an interesting problem for the Red Storm, in that rotating the monitor counter-clockwise for vertical games, puts all these inputs facing the top of the cab, which does not fit the fame's design.  
You can rotate the monitor clockwise (the wrong way) and have the inputs facing the bottom of the cab, only in this configuration, you'll not be able to attach the top marquee since the mounting holes are now also on the bottom, but more importantly, you'll only be able to play jamma games that support a screen flip option (most do but some don't).  However, I did find a solution to this strange issue, which involves rotating the square chassis on the back of the LCD 180 degrees.  This takes an additional 2 minutes while the LCD is off, and the wires support flipping the chassis around.  Now when you mount the LCD back on the frame, its oriented properly (counter-clockwise) and inputs are facing the bottom of the cab

[Update!] Since this original posting, I received a set of low profile Power, VGA, and HDMI cables from GameCenter Arcade, which now allows me to rotate the monitor proper without having to flip the chassis on the back.  So in total, rotating takes about 2 minutes (just unscrew 4 hex bolts from the back, rotate, and screw back in.  This is actually faster than rotating an Egret II if you consider the time it takes to also rotate the bezel.
Now lets take a quick look under the hood.  You'll see in the pictures above, a very convenient light when the cabinet door is open, a shelf for your PCB, an adjustable main jamma power supply, and a stereo amp with its own independent power supply. Behind the coin door (not shown) is a modern coin mech with electronic coin comparitor, and illuminated power switch with standard test and service buttons.  Wiring is for straight jamma (no JVS) with a VGA cable for the monitor.

Under the lighted control panel, you'll find a typical Chinese CGA2VGA scaler.  This version is seriously budgeted to only take RGBS input and VGA output, although the firmware supports component input.  I added my own SGL3000 to add realistic scanlines at 640x480 which does make a world of difference when playing low res PCBs.  Button and sticks on the panel are typical Sanwa JLF controls.

On the back of the cabinet (not shown) are 4 fans, two large 4 1/2" and two smaller 2 1/2".  This creates a large amount of cool airflow inside the cabinet, which is good news if you want to put a console or PC inside.  Also on the back are a set of versus connectors (and cable included) for hooking two cabinets together.

Light up marquee and instruction strip are a nice touch, although both use non-standard sizes, which really sucks for the instruction strip as its significantly shorter than the typical Astro City size. 
LCD cabs are not known for displaying great pictures for low resolution 15khz PCB games, and this holds true with the cheap scaler included in the Red Storm.  However, I was pleasantly surprised that the cabinet was able to sync and display a picture for oddball refresh rates like 54hz for Seibu games!

Of course the cabinet really shines when displaying HD games for Taito Type X/2 and modern consoles.  I especially like that most vertical arcade games for XB360 allow me to rotate and position the 4:3 picture with a background image filling in the remaining area.  Of course you'll need to supply your own console-to-jamma solution to hook up he controls, but there are many options available on the market or homebew for doing this.

Overall construction of the Red Storm is surprisingly good, with quality components, and well thought out access panels and hatches for the back and monitor/LCD.  Some corners were cut when constructing the base, where I found screws holes that were not tapped properly (they were just drilled holes with screws), and the paint job around the speakers pods looked amateurish. I'll likely be investing in a better stereo amp (the sound is quite thin), as well as a better scaler for the 15khz mode.  I didn't notice any LCD lag, but I've herd this model may have 1-2 frames of lag for pro's playing SSFIV, although it appears the chassis can be easily upgraded/replaced.

Saturday, March 10, 2012

Jaleco (NMK) shmups

Received these two Jaleco PCBs over the weekend.  Both were actually developed by the team that would later form NMK, and their difficulty prove it, especially Saint Dragon!

Sunday, February 19, 2012

Sega Naomi video problem

Here is a quick fix to what I believe is a common Sega Naomi video problem.  I've seen this happen on two Naomi motherboards I own, as well as on a Hikaru motherboard.  Video looks to be smeared or ghosting, like in the picture below.

I don't know exactly how it happens or why (I'm too lazy to really investigate at this point), but the problem is with the filter board (not the motherboard).

After removing the filter board, turn it over and you'll notice a burned trace just under one of the long connectors.  This pin is one leg of an RC network that goes to the VGA port, and then runs under the connector to another set of pins above it.

The fix is simple, jumper the two connectors to bypass the burned trace, and your video will look crisp as new.

Happy gaming!

Sunday, January 08, 2012

New Years resolution

With the new year comes resolutions, and this year I am pledging to learn how to diagnose and fix common PCB failures.  Over the years I've been steadily contributing to a collection of broken PCBs, some that I think could be fixed easily, and others that I think require deeper investigation.  Not having an EE background, I've had to learn much of what I know on my own, and will try doing more of that this year in troubleshooting circuits.

The most common failures with PCBs I've noticed, happen during handling: be this incorrect packaging during shipment, or incorrect storage, or even the act of plugging them into a jamma harness inside a cabinet.  In all these cases, the PCB flexes, causing solder joints or traces to crack, or pins on SMT chips to lift from their pads.  Very few failures happen due to static electricity (ESD) while handling...of course this is my own observations, maybe I'm just more careful than most when it comes to ESD.  Lastly, environmental situations can cause a PCB to corrode, or capacitors and batteries can simply leak over time.  There isn't much we can do about this, other than look for the warning signs and then take action.

So I kicked off the new year with buying a Weller WESD51 soldering iron, as my previous Radio Shack 15/30 iron wasn't up to the task of  soldering delicate SMT chips.  I also invested in building a bench top supergun consisting of PC power supply, jamma harness, CGA-to-VGA upscaler, and rotatable small/cheap LCD monitor.  I'm not worrying about input controls at this point as the broken boards I have can't boot up or have graphical glitches that are noticeable without playing the game.

Above is a pic of my bench with a broken Alcon PCB.  The monitor is a small 15" HP 1502 that I got for $30 shipped, I then mistakenly bought an incompatible HP rotatable stand, and had to hack the monitor up a bit to make it bolt to the stand.  I would recommend finding an HP 1530, as its the same small monitor but comes with a rotatable stand and stereo speakers built in.

Next is a standard CGA-to-VGA upscaler you can find on eBay for $35-$40.  I bought one that came with a jamma adapter and RGBHV and power wires for an additional $25.  This makes it very easy to hook up to any jamma harness with an LCD or VGA monitor.

Last, I bought a jamma harness with PC power supply, and provided my own 8ohm stereo speaker I had laying around.

So far I've noticed this setup isn't compatible with games that use a refresh rate below 60hz such as the Raiden series, and a few miscellaneous games.  I am investigating some really fun alternatives to this setup, so stay tuned.