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Friday, January 06, 2017

Twitch streaming arcade PCB's

(Double playing Mad Shark)

Exactly 4 years plus second child later, and I'm back to update this neglected blog with a little something I did over the holidays.

Twitch live streaming has become quite popular, and I've started following some friends that stream live PCB plays.  Given I've got a unique collection of not only PCBs, but also of cabinets and arcade controls, this was a great opportunity for me to try and share more of my gaming treasures with the rest of the world.

For PCB/RGB capture I used a StarTech PEXHDCAP card I bought many years ago, as it was a cheap OEM version of the great (and expensive) Micomsoft SC-500N1.  Startech has since discontinued this and released a PEXHDCAP2 version, with reduced input features, but higher capture framerate for HD resolutions.  In addition to RGB/VGA input via the DVI port, the original PEXHDCAP also had HDMI, Component, Composite, and Stereo inputs. The only draw back was 1080p could only capture at 30 frames, but I didn't have a need for that.

The minimum PC specs for the PEXHDCAP was an Intel Core 2 processor with 2GB ram.  And it just so happens this is all I have in terms of a crappy PC with PCI express slot (I'm not much of a PC gamer if you haven't noticed).

Since PCB RGB is typically 1V and PC Analog RGB is .7V, taking the RGB/Gnd/CSync lines from your PCB and running straight into the DVI port (via VGA 15 pin adapter) is going to give you a washed out bright picture.  To adjust the RGB levels, you're going to need a CGA to VGA adapter (like this found on eBay).  No conversion actually happens, it just routes your RGB lines to the 15 pin adapter, but does have adjustable resistor pots on the RGB lines to bring levels down to PC analog spec.  I then run this via VGA cable into the DVI input (with VGA to DVI adapter).

Routing audio from your PCB into the PEXHDCAP's external audio break out cable will also take a bit of hacking to tap line level audio from the PCB's amplified sound.  I'll have to follow up with an actual circuit for this, but basically you need a resistor, a cap, and a mono input jack.  I just happened to have a prebuilt headphone line out with volume pot which did the trick.  I've seen others just use an external microphone setup next to the cabinet speakers, which can also be used to pickup your voice, but you won't get good quality sound from the PCB.

Last is streaming software, which is pretty well known if you've ever tried to stream something from your PC.  I use OBS which is plug and play ready to work with Twitch.  There are plenty of tutorials out there on how to set this up and configure plugins, so I won't go into detail here.

I almost forgot, most players also have a webcam setup to show off their joystick prowess, or to show their face, adding more personal interaction while streaming.  The webcam I use is a Logitech Quickcam Pro 9000.  This is pretty much the cheapest 720p camera out there that is compatible with Windows 10.  One issue I did run into was trying to run two quickcams plugged into the same PC to show both my hands/joystick as well as my face.  The issue is that two of the same cameras can't be plugged into the same USB bus as they will both resolve to the same USB address.   Buying a second PCI USB adapter (~$10) solves this, and also alleviates any framerate/bandwidth issues running on a single USB bus.  Turns out my crappy Intel Core 2 started to choke with two cameras and PCB capture at the same time, so I trimmed down to a single camera, and am back to a mostly 60FPS stream at 1280x720.

I've already tested this setup on several cabs, including a medium res game, and VGA (Sega Naomi) game and it works great!  So expect me to be streaming some Planet Harriers and NARC in the near future.  I'm typically on for a half hour at night after my kids go to sleep, maybe once or twice a week.  You can checkout my twitch page here, and be sure to check my saved streams.

Sunday, January 06, 2013

Heavy Unit

Sorry for the lack of blog updates.  "Real Life" has gotten pretty busy with the birth of our first child, but that hasn't kept me from picking up a few random PCBs over the holidays.

First up is Heavy Unit, a relatively unknown Taito published shmup on Kaneko hardware, and apparently was unemulated up until the end of 2010.  You can still find this pretty cheap in the US, so I went ahead and got one.

The detailed artwork is rather nice, a mix of bio-horror and mecha type enemy and scenery.  You have standard powerups for your A and B shots (no bomb button), and a transforming powerup that switches your ship to a mecha.  Unfortunately the game suffers from lack of autofire, which means a very sore wrist without (or much easier game with) autofire.  Rank seems to depend completely on your powerup level, which is nice when you die, as its not too difficult to get powered up again.

I haven't had enough time to play this past the first few levels, and I like the detail and variety of enemies, but feel the game may be too easy with autofire.  Bosses go down quite quickly if you are fully powered up.  I'll come back to this when I get more time to clear the game.

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.

Sunday, December 04, 2011

Reset highscore table on Cave SH3 PCBs

If you bought Mushihimesama or Espgaluda II Cave SH3 boards used, chances are you have a bunch of very high scores logged in the permanent hishscore section, with no chance of entering your own initials - outside of "Today's Highscores", which erases when you power down the board.  So what's a mediocre shmup player to do?  Well thanks to kernow for starting this thread on the shmups forum, and to rtw and idc for replying with an answer, I bravely tried the procedure on my Mushihimesama PCB.

**** WARNING! ****  I take no responsibility if these instructions lead you to frying your PCB. Proceed at your own risk!

What you need is a 100 ohm resistor (pictured below is actually a 97 ohm precision resistor).

With the PCB turned OFF, first remove the battery, then put one end of the resistor to ground.  You can use any ground.  I found the hole of pin 5 on the missing serial connector a good place so it wouldn't move.  Then carefully hold the other side of the resistor to pin 9 (Data Output) of the RTC/EEPROM (U10), and power on the PCB.  The bootup sequence will first check the program code, and then checksum the EEPROM.  Its at this point, the checksum will fail, and the board will re-initialize the EEPROM, so quickly remove the resistor as soon as you see the EEPROM "initializing".

Since these surface mount chips are very small, and you don't want to accidentally ground other pins on the RTC chip, I used an exacto knife to cut and place small squares of electrical tape to isolate pin 9.

You can verify the procedure worked by going into the operator menu and checking the ranking display.  Here is the before and after shots of Original mode scores on my PCB.

Note: Ibara, Pink Sweets, and Muchi Muchi Pork have an operator menu setting to clear the ranking display (thank you Mr. Yagawa!).  Deathsmiles also has a reset ranking option.  I do not know if Mushihimesama Futari or DoDonPachi DaiFukkatsu boards have this option as I do not own these yet. :)

Saturday, November 12, 2011

DIY Speaker Sheilding

I've always loved vector games of the 80's, and spent many a coin on Asteroids and Battlezone back in the day.  Plus, the vector graphics looked ahead of their time back then, so that only made these games seem much more appealing.

Anyway, over this past summer I had an opportunity to buy a vector cabinet locally, and jumped at the offer, considering the game was in such great condition.

Space Duel is an interesting two player cooperative take on traditional Asteroids.  Plus its a color vector game!  There was only one problem I noticed with the cab, and that was a color blooming issue in the lower left corner of the vector tube.  Actually it was more than just color, the convergence of the tube was pulling in that corner, but he adjusted the picture to be smaller in the center of the screen so the vectors weren't as affected as the colors were.  This defect helped me in negotiating the price on the cab, and in my mind I thought it was really just a degaussing  issue.

After getting the cab home, and using an external degaussing ring,  the color blooming was not going away. I open the cab and inspect around the tube to make sure there was proper shielding, and noticed the original speakers under the control panel, and above the monitor were swapped out for larger size cones, presumably to give it better bass response.  Larger speakers also means larger magnets attached to the back of the speakers, which were upsetting the magnetic balance the cab was originally designed for.

Since these are not high end car audio speakers with protective shielding, I would with have to either replace the speakers with original spec, or try to shield them myself.  I chose the latter since the four larger speakers makes this cab sound tremendous!

A quick googling led me to Andy Rondeau's Do-It-Yourself (DIY) Speaker Project. Although at the top of the article, he states this information is now outdated (as you can now buy expensive speaker shielding kits), I liked his DIY approach with cheap Home Depot supplies.

So I measured my speaker drivers, and went to Home Depot to look for those same steel pipe cap/ covers (which were about $5 a piece).  I also found some electrical boxes (for $1.50 a piece) with much thicker steel and approximately the same size, which fit quite snugly inside the cap covers.

I decided to return the more expensive cap covers, and just stick with the cheap electrical boxes as combined they didn't seem to add any additional shielding from my testing.  The boxes were a bit larger than the two speaker drivers behind the marquee, but fit perfectly over the speakers under the control panel.

(Note how close one speaker under the control panel is to the chips on the PCB!)  

I used electrical tape to ensure the boxes didn't fall off, and to insulate the edge next to the speaker terminals.  The results were amazing!