So, What’s Inside a Sega ST-V Game Cart (And Differences)

Over the past few months I’ve picked up a few Sega ST-V games.  The ST-V was an arcade system based on the Sega Saturn.  The budget arcade board of it’s time as the main Sega releases were all coming out on Model 2 and Model 3.  The CARTs are quite big and I want to see what’s inside so this post is just about opening and having a look around.


A Stga ST-V cart (Front)

This is the CART in question a very silly Colums like game called Baku Baku Animal. Looks pretty easy to get in to.  Clips on the top and two screws on the back bottom.


Retaining screws

Annoyingly, these are security screws and they are in quite tight.  I know this is done for ‘reasons’ but it’s very annoying.  Happily I have a tool.


Stupid  Security SCrews

This is a 4.3mm ‘Game Bit’ that I bought to open up SNES CARTS.  It fits these security screws perfectly though. Remove the two screws.


4.3mm Game Bit

Once the screws are removed the bottom of the case can be seperated and these two tabs/clips can be pressed to seperate the top of the cart case.  These feel quite delicate though so be careful!


Top retaining clips

Once open we see the front of the cart.  It even fills most of the  space inside the plastic shell.


Front Removed

Taking the PCB out and looking at the front side, everything is really well labelled.  There’s a row of ROMs at the top, filter CAPs in the corners, a couple of ICs (Octal Bus trancievers) and a custom Sega chip at the bottom (guessing this is the program ROM).


ST-V Board Front

The Rear of the CART has space for more ROMs but this is a small game so not used.  Just a row of Octal Bus Trancienvers.  These are used fo 2 way communication (Async) between the ROMS and the controller chip/system.


ST-V Board Back

A close up of the trancievers. All the same part: “3-STATE Octal Bus Transceiver” (guessing the 3 states are send, recieve and off)


IC line

Here’s a close up of the game ROMS.  These are 32Mbit ROMs.  Specific to the game on the cart.


So that’s the inside of a Sega ST-V cart.  I did then take apart another game that I had issues with, Decathlete.  This game was working finemost of the time but had a habbit of freezing at random.  I was worried it was bootleg So I opened it up…


Sega Decathelete

And found this.  From research this is legit and how it came from the factory but the program ROM is a socketed EEPROM (like the ones used for NAOMI BIOS chips (Same label and font).  It’s not super visible in this picture buy 1/4 of this chip was loose in the socket.  Pushing it back down again seems to have solved my issues of freezing.


Socketed Program ROM

The other interesting item on this board is a Sega branded chip the 315-5838.    This is not present on any of the games I have with non socketed Program ROMS (I opened a few others.  I Think this is a comms / decryption chip to stop people simply copying the EEPROM.  I can’t be sure though.


Custom Sega Chip

So that’s the inside of a Sega ST-V cart.  Actually more interesting than I initialy thought and a good example of a mid 90’s budget arcade system.










Posted in Arcade, Games, retro, Sega ST-V, Software, Teardowns | Tagged , , , , , , , , , , , , , , , | Leave a comment

Sammy Atomiswave – System Pickup and Tear Down (95%)

My latest pickup, and something I’ve been on the lookout for a while (as always at not stupid B.I.N Pricing) is an Atomiswave system by Sammy.  This is the cheaper, slightly less powerfull version of the Sega Naomi (i.e. less RAM).  This actually came out AFTER the NAOMI 1 and NAOMI 2 systems just as arcades started going downhill again in the early-mid 2000’s.  Basically a Dreamcast in arcade clothing that runs on JAMMA (with VGA output) so it has great compatibility with old and newer arcade cabs and I’m guessing this was kinda the point given when it was released.


The Sammy Atomiswave System

The system itself is in rather good shape (certainly better shape than the abused NAOMI systems you always see).  Howerver, this has two holes drilled in the side of the system so it looks like someone has done, or tried to do, a stereo Mod at some point.  Will be interesting to see if this is a hack job mod or if any remnents still even exist.


Holes for Stereo RCA jacks

So, time to take it apart and see what we can find inside.  Removing the plastic covers for the expansion ports (used for things like inter cab communications board and the gun controller I.O board) reveals 6 screws that help secure the top plate of the case to the main chassis.  Remove these first.


All the Board Connectors

Now, on the front edge of the case, there’s a retaining screw in between the JAMMA edge connector (totally standard) and the remaining I/O ports on the right.  These are the DIP switches (for setting test mode and 15/31Khz modes), the volume wheel, a connector (CN3) that is for Stereo sound output via an adapter (that I don’t have), the VGA output and a serial port.  It should be noted that, as long as the monitor you’re running through can accept 31Khz via it’s Non-VGA connector you don’t NEED to plug in a VGA cable to use 31Khz mode  It will output 31Khz over the JAMMA edge.


Front I/O

This is a close up of the DIP Switches.  There are a little stranger then most I’ve come across as they ‘seem’ to operate in the opposite direction to how I think they should.  ‘On’ is flicking them DOWN and AWAY from theswitch housing (arrow shown).


DIP Switch Close Up

Flipping the case around reveals one final retaining screw and the FAN exhaust port.  Thankfully this is not as noisy as the NAOMI boards (I know I keep making the comparison but they really are so similar…).  It makes an audible hum, sure, but with game audio simply ‘on’ it’s not really noticable.


Rear Retaining Screw

Turning the case over reveals nothing….  this seems to be the main plate everything inside is mounted to (see the copper Motherboard standoffs visible and some venting holes).


Atomiswave Underside

So, the red top cover will now lift and slide off the rest of the case (up from the back and then slide over the JAMMA edge).  Doing this reveals a mettal Shield protecting the motherboard.  Undo the 5 shown screws and unplug the fan in the top left.  This loosens the plate but it can’t yet be removed due to  the small PCB in the bottom right stopping the plate from coming off.


Metal Shield Under top Cover

Here’s a close up of the part that needs to be removed in order to proceed.  It’s the board containing the volume control and Serial connector.  The serial connector port binding posts (Shown) will unscrew by hand if loosened with a set of pliers (just grip and turn counter-clockwise).


Serial Port Retention

The only thing stopping this board being removed now is this small plasticclip (left side of board).  This holds the board securly in place but, as it’s plastic, could be brittle.  Carefully compress the clip part and you should be able to simply pull the board up and off the plastic post.


Plastic retaining clip

This is the removed board.  A serial port and a variable resistor fo the sound.  The wire connector pulls out easily, there’s no locking clip and it’s keyed so it can’t be put back incorrectly.


Removed board

Now this board is removed we can see the area on the main PCB where the legs of the ‘CN3’ connector push through.  This is the stereo sound connector and shows where a previous owner has attempted to put a stereo RCA mod on to the board.  Clearly they have given up as this is all that remains of the attempt (outside of the holes on the outer case).  The idea would have been to solder wires to the L, R and Ground pins here and then attach them to RCA plugs on the case.  Thankfully, the remnants of this attempt came off really easily.


Botched Audio Mod

The main board has a VGA connector with the same retention screws holding it to the case.  Same as before,  unscrew to continue.


Video out Connector

More screws next with another 4 screws holding the motherboard to the chassis.  The top two are threaded slightly differently so ensure  you know which screw goes where.


Final Motherboard Screws

And now it should be possible to remove the motherboard from the chassis… but it isn’t… it turns out that the design of the Atomiswave includes an integrated heatsink.  But, in this case the CPU and GPU are thermally glued  (via adhesive pads) to a metal heat spreaderitself attached to the chassis.  Great for keeping the costs down and the heat at bay but rubbish for teardown and curious people.  I could technically remove this with a bit of heat and a spludger but i’ve not got any replacement pads and I do want to use the system. So, lets just look around as best we can without removing the board from the chassis.


Enter a captionCPU and GPU thermal pads

The actual design is interesting.  Heat from the GPU and CPU transfer to the metal heat spreader.  This is hollow and attached to the chassis backplate.  It’s also orientated that the exhaust fan pulls air through the gap cooling the system as it goes (direction shownvia arrow). I like this.  Very efficient!


Clever HSF/Air Flow Design

Looking through from the other side we cn see the backup area for the score saving / book keeping battery.  This looks like a standard rechargable Lithium button cell battery.  Happily this has sealed edges so 20 years down the lineit shouldn’t leak and kill the board (unlike every MVS system ever).


Battery Backup Area

Next up to the right is another integrated heat sink which looks like the audio amplifier as it’s connected to the ribbon cable that connects to the variable resistor on the sound control board.


And thats about it for interesting things that can be seen without taking the whole board away from the heatsink.  Now to put it together and go play a game 🙂



Posted in Arcade, Arcade Hardware, Atomiswave, General, Hardware, Teardowns | Tagged , , , , , , , | Leave a comment

Inside Metal Slug 6 (bootleg) Atomiswave Cart

I recently picked up my first Atomoswave board and it came with a copy of Metal slug 6.  Which was nice.  Now, I’m a huge fan of the series but, having played 6 before in the arcades and being a little underwhelmed I’m not super bothered if it’s original or not. This one most certainly isn’t legitimate. Happily, all bootlegs seem to have the same serial number on them so I KNEW this at time of purchase (and the price reflected this).

It works, so the obvious thing to do now is see what’s inside and if it’s as much of a hack up as most of the old Neo Geo MVS boots tended to be (with wires and EPROMs everywhere).


Same Serial Numer, giveaway

Flipping the cart over there’s a very obvious set of 4 x phillips screws to undo that should allow me access to the main PCB.  No ‘warrenty void’ stickers or anything (well, it is a bootleg).


This looks easy

With the metal plate off we get a good view of the underside of the main PCB.  Not very interesting…  A connector, some traces and a small sticker helpfully telling me this is a Metal Slug 6 Board.


Opened up

Taking the board out it does, indeed, look very clean.  I don’t know if the writing on the sticker is the S/N of the bootleg or something else…  Note the holes on the top left and bottom right edges of the PCB (next to the screw holes).  These are guide pins to stop the PCB being inserted in the wrong direction during assembly.  So far, this is a well made bootleg.  I mean, that sticker is even straight!


Clean, well made, straight!

Flipping the board over to reveal the front of the PCB is far more interesting.  ROMS and chips galore!  Again, a very clean layout and quality job. No EPROMs or hacked in wires / resistors, just a regular repro production run.  Taking a closer look at the chips for identification of function and type though reveals…..


Front of the PCB

…Nothing.  Every single chip on the board has had its identification and markings sanded off (neatly) so there is no way of identifying the components used or the supplier (I’m guessing this was the point).  Still, there’s been multiple levels of quality control (or multiple stages of QC stickering) so, again, looks like a quality job!  I’ll have to revisit this a little later when I have a legit cart to compare against so I can work out the chip functions (I’m pretty sure the long one populated in the bank of 4 is the main storage ROM thought).


Sanded off chips

Not much else to say about this cart really.  It plays fine with no graphics wobbles and it doesn’t need any jigelling around in the motherboard to make it work.  A good experiance really.  Obviously it’s not legit so it’s not ‘worth’ anything.  Happily, anyone buying this should be able to spot a boot quickly with the serial numbers all being the same and it being VERY easy to check the ROMs by asking for a ‘legit’ cart to be opened.  You’re not gonna dammange anything by checking.


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Arcade Buttons – Keeping Them Working (Dissassembely and Cleaning)

Arcade Buttons.  You know, the standard convex colourful plastic type that you get on pretty much all candy cabs and modern console ‘fight sticks’.  They are one of the few items in the arcade game hobby that can still be considered a cheap, easily availbale, part.  But, with a standard 2 player control panel having 14 of them (including start) it’s still an expense.

It doesn’t take that long for a button to start to not rebound quickly, stick or even fail to register a press now and again. This is amazingly frustrating when youre going  for a 1CC on whatever is the game of the month.  They fail even quicker if your kids spill a popular branded fizzy drink over the control panel and then not tell you about it for a weekend.

Thankfully, servicing these types of buttons is dead easy, very cheap, and results in the button feeling as if it were new again.  I found this method via a video from Luke Morse (link here) .  This is simple a pictoral version of me doing what he describes in the video in the hope that the more places this information is available, the more people will be able to fix their own gear.

The buttons shown here are standard Sanwa OBSF-30 ‘push in’ buttons most commonly found on japanese candy cabs.  In my case, player 2 side of a Blast City Control panel. Anyway,  to get your buttons working again…

Cleaning Method.

First up, Remove the buttons from the control panel itself.  Disconnect the wiring for the buttons from the pins (They Pull straight up and off).  These are wired in pairs (button x + ground) It doesn’t matter which wire of the pair goes to which pin but you will want to note which pairs got to which button so they can be re attached in the right order. NOTE: I know the pic below are two different pannels… It was easier this way!

Now you can remove the buttons.  These are push fit so simply apply pressure to the two tabseither side of the button (one side shown below) and the button should pop right out of the control panel.


Holding Tab

With the button out we can see the damage and goo thats acumulated and stopping it from working great.  We need to get rid of this  gunk.


Euuuck… Sticky

We’ll need to clean inside and out so, turn the button on its side. and notice the two clips keeping the top of the button in place.  Gently, with not too much pressure, push these tabs free of the main housing and remove the top.  NOTE:  You could snap these off if you push too hard.


Button top release tab

Now, with the cap off we can see theres a good deal of gunk on the cap itself and on the inside of the botton housing.  THis is causing excess friction and messing up the correct opperation.


Gunk Inside



Dirt and gunk on button cap

We have one more thing to remove before cleaning.  The microswitch itself.  This is a black rectangle at the bottom of the housing.  Easy to remove.  Turn the housing upside down, press on the two clips either side of the switch and it should pop right out.


Microswitch Holding Tabs


Empty Casing

Now, to clean the housing and cap, simply use a soft cloth (I use a dishcloth) and some standard cleaning spray (I used kitchen surface cleaner)  Spray the plastics and wipe off any of the dirt.  Careful with the microswitch,  just use a damp cloth on this.


Clean Cap

With the dirt off it would be tempting to just re-assemble and put back together but, to get that super smooth action, grab some bike chain lube (Dry lube recomended) and dab some on to the edges of the button cap.  With a clean cloth work this around the edges of the cap.  Repeat for the inside walls of the housing.  Now, when reassembled, the two pieces of plastic that are likley to touch have lubrication.  I’ve found this to be very hard wearing and lasts a long time.



The Assembled Button

Now assemble in the reverse order by putting the microswitch back in the housing, the cap on the button, the buttons in the pannel and then the wiring back on the pins.  You should have a fully working, highly responsive button.


Buttons Wired (Back how it was)

Now you should go play some games with the responsiveness of a new button 🙂

Posted in Arcade, General, Hardware, Repair, Restoration, Troubleshooting | Tagged , , , , | Leave a comment

Looking Inside A Razion LE (NG:Dev.Team) MVS CART

I recently had a bit of luck by managing to find a copy of Razion for the Neo Geo MVS at a sensible price.  The original manufacturers were doing a reprint of the game (hardly ever happens) so a copy of an already used “LE” version was up for grabs for a sensible, and comparible, price.  So I got it… and now I ant to know what’s inside it….

First run NG:DEV.Team games are a little different to regular MVS carts.  Essentially it’s the same game as the reprint but it comes in a wooden MVS shell.  There’s some included  ‘fluff’ I dont really care about also included in the box (like posters, art work etc.)

Of course, as this is a non standard SNK CART, I figure the insdes are going to be different to the usual SNK MVS boards (should be given it’s boasting 1560 MEGS).  So lets take it apart…  Here’s the CART (LE version).

Razion LE Cart and Board (6)

Spine: Nice Label, Wood Finish

The spine is nice.  The wood shell isn’t two halves that seperate where the label is like ususal MVS games.  Instead, the underside of the shell unscrews leaving the label in pristiene condition.  Good thinking NG:Dev.Team!

Here’s the top of the cart with vent holes and the hologram serial number.

Razion LE Cart and Board (5)

Top of the Shell

This is the underside of the CART.  With the 4 screws holding the wooden plate to the rest of the CART.  They are simple phillips head screws so lets get them out and see what’s underneeth.

Razion LE Cart and Board (4)

Underside: Vents and screws.

Opening up the case and we are greeted with…  A very dull picture.  This doesn’t look that interesting, some 2/3 height PCBs with the interesting stuff facing away from us and, what looks like, some form of connector at the top.  Lets turn them around and see what’s there…

Razion LE Cart and Board (3)

Opened up: the anti-climax shot!

once we’ve extracted the PCBs (snugly fitted in to the case, no wobble!) We see the large chip on the far left being a 512Mbit ROM surrounded by edge trigger chips (don’t know what they do).  The large chip in the center is a NXP microcontroller chip.  These contain USB and memory controller so I’m guessing this is used as the communications bus between the chips onthe right and the ROM boards, RAM and USB header.  Below to the right of that is a Xilinix CPLD (Complex Programable Logic Device) and further over on the top right we have a Spartan FPGA (Field Programmable Gate Array) with more flash rom below.  FPGAs need configuring at startup so I would guess this ROM contains the configuration for the Spartan chip.

Pure speculation here but I would also guess the Spartan chip constitutes the “MCU” you sometimes get a reference to in the game if there’s a error and it needs a reboot.  An FPGA is essentially custom and per task definable so whatever this does, NG:Dev.Team programmed it to do it…  I’ll never know.

Razion LE Cart and Board (2)

PCB 1: The Main Prog board

The next board back is pretty self explanitory in its function but also rather interesting.  It’s theROM board holding all the game asset data.  The top left 2 chips are both 16Mbit NOR ROM chips (I assume for program and sound data?).  The right 2 chips are 512Mbit ROMs which are probabaly the graphics roms.  the row of chips below are a bit of a mystery to me.  Tne Ti branded ones are “Octal edge trigger flip flops” whatever the heck they are…. a wild guess….  paging the ROMs so the MVs can read it?  dunno. If you do, PLEASE comment!

Razion LE Cart and Board (1)

PCB 2: The ROM Board  (or ‘vault’)


The game itself is blooming brilliant.  A very tough, but fair shooter with an excellent soundtrack, great scoring system that rewards risk and a good variety in the levels (although it accelerates from good to great from level 3 onwards).  Linked below are a couple of videos of it running on actual hardware (Sega Blast City, CRT and MVS).

Razion Level 1 Playthrough (Real arcade Hardware, Neo Geo MVS)

Razion Level 2 Playthrough (Real Arcade Hardware, Neo Geo MVS)

Until the next pickup….

Posted in Arcade, Arcade Hardware, Games, General, Hardware, Software, Teardowns | Tagged , , , , , , , , , , , , , | Leave a comment

Inside a Super FX SNES Cart (Another Opening Up)

Back when I was 12 years old I was completly blown away by the Graphics from a certain game by the name of Starwing (Starfox to the rest of the world).  3D Graphics from a 16-bit console? Witchcraft I say!  In Reality this was simply a co processor in a game Cart that enabled the SNES to do 3D (in a really boarded window at somewhere around 9-13 FPS with virtuallly no polygons on screen by my estimation).  Still, I wanted it and I never got it (it was £70 in 1993 for pittys sake).  UNTIL NOW! where I found this little beauty in my local CEX for £6…  So i thought I’d open it up and see what all the fuss was about 23 years ago…


Starwing / Starfox / Whatever

Time to open this thing up.  As before it’s all held together with 2 gamebit screws (3.8mm) and comes apart pretty easily after unscrewing them.  When I opend up a Legend Of Zelda CART I was shocked at how little of the space in the CART housing was actually used by the PCB.  Not in this case.  Full utilisation 🙂



From the back we can’t reall tell anyting other than ‘it’s big’.  So lets flip it over and see where all the magic happens.  Much more going on here then a regular cart (just in terms of traces on the PCB!).  Center top we have the game ROM, Bottom left looks like the security chip.  Above that is probabaly the lookup / addressing chip (I cant really work out what it is though so it’s a guess). Which leaves us with…img_6062

The ‘Super-FX’ chip itself.  Mappily labelled here as ‘Mario Chip-1-100’ this is where all the 3D processing gets drawn and spat out bacn to the SNES itself.  If you look to the right we also have the 256KB RAM chip.  No wonder this thing cost a lot back in the day. An on cART processor AND memory….


It’s-a-me Mario(Chip)

So now I know….  I quite like the design of this really.  Not that complicated and, despite looking like garbage now, it really did push the boundries of what was possible back in the day.  Time t put it all back together and go play a game of StarWing (Which turned out to be really, really easy….).

Posted in retro, SNES, Software, Teardowns, Uncategorized | Tagged , , , , , , , | Leave a comment

So, What’s Inside a SNES Cartridge (Opening and Poking About)

As part of my attempt to clean up and get working my SNES from the dawn of time  I thought I’d take a look inside the game cart I have.  Not for any reason… I’m just curious and happened to have the screwdriver bit that would allow me to look inside (it would be rude NOT to take a look).  The Game inquestion?  Zelda: A Link To The Past


Zelda: Limited Edition dirty version

Zelda is an awesome game and allowed saves (vs passwords) So I’m expecting to see some form of battery backup inside the game.  Opening one of these carts is simple. Undo the two security screws on the front of the case (3.8mm Gamebit) and the case will open up (careful of the clips at the back / top).


Not sure this could be dirtier

Once you’re inside the cart this is what you see.  Absolutly nothing special or interesting from the back.  I’m actually a little surprised that the case has this much empty space in it.  Time to take out the PCB and see what the front looks like.


Rear PCB, not taking much space

This is more like it!  Although I must admit it’s far less complicated than I was expecting.  I’m used to seeing the inside of Neo Geo carts or arcade ROM boards with banks of ROM chips in a neat row.  From a bit of deduction and PCB reading it looks like the save game area is the chip on the top right of the pic below with the battery feeding it power on the left.  This, amazingly, still works and is holding the previous owners save game from years ago (annoyingly, not date stamped)!  Bottom left is a Nintendo branded chip.  Pretty sure this is the security / handshaking chip in the cart to avoid fakes / pirates etc.  Above that is a Motorolla chip that is probabaly the memroy mapping / address lookup processor chip.


Front PCB with battery (RAM on the Right)

And, finally, we have the Mask ROM holding all that lovely Zelda game goodness.  marked onthe PCB as U1 ROM and a pretty standard Toshiba chip


Zelda: All of it…..

So there we have it.  The inside of A SNES cart.  Apart from a working battery, nothing super exciting.  Still, glad I looked and now I know!

Posted in Games, retro, SNES, Software, Teardowns, Uncategorized | Tagged , , , , , , , , | 2 Comments