Ian Primus

Here's Sam, helping out with Unix. While there is a cat command, I don't believe this was the original intent: cat fuzzy.txt -Ian

I considered buying an encoder, but then I realized that the one thing the cabinet was missing was a frustrating and tedious soldering project! Gamepads are easy compared to what I did. I built my cabinet in the pre-ipac days. I hacked up a keyboard. A well-travelled, missing many keys, IBM Model M was sacrficed for my cabinet. I traced out the matrix, and wired up all the buttons to the keyboard's encoder board. Of course, this means, there is no common ground, so every button needs two seperate wires. I have not had problems with "ghosting" on the keyboard - but then again, it's a one player cabinet. I kept it simple and clean. One of these days I need to get around to upgrading my MAME cabinet. At the time, I used what was still a fairly expensive computer - a 266mhz Pentium II, with 64 mb of RAM. These days, I have Pentium 4 machines laying around, collecting dust. -Ian

Open the console by removing the philips head screws from the bottom, and lift off the top. In the center, slighly below and to the right of the cartridge slot is a hole in the aluminum housing. Look into it - there should be a variable inductor in there - it looks like a red plastic tube, and inside is a ferrite slug. Using a PLASTIC adjustment tool, gently move this back and forth until the sound comes in better. The hole in the lower left of the aluminum housing is the color adjustment pot. If the colors are off, adjust this with a small flat blade screwdriver. This inductor adjusts the sound tuning. You must be very careful not to break it - a metal tool (like an allen key) will break the ferrite slug. Any decent electronics shop should have a set of plastic TV adjustment tools, which will include the tool you need to adjust this. Alternatively, you can whittle down something like the tab on a pen cap to fit - it shouldn't need to be turned very much to fix the sound problem. -Ian

Maybe.... possibly... Here's the thing - I'm really good at fixing Ataris. I'm really good at fixing a large variety of things actually. But I've never even seen an Astrocade before. But, since there's all this talk of how failure prone they are, I'd like to find a couple to take apart, and figure out. I don't know if I'll even be able to fix them for people - because for all I know there's a failure-prone custom chip that I won't be able to get. I won't know until I try. I just don't want to take on a "fix this for me", until I know more about the machine and how it works. -Ian

I do, provided the game is cheap and my old one is bad. I'm not picky enough to upgrade carts that have only minor wear - but, if I found a copy of "Frogger" that actually still had a label, I'd buy it. I also purposely buy a lot of games in bad shape (if really cheap) to re-use for projects. -Ian

Yeesh. Maybe someone left it outside in the late 80's and just now found it again... Actually, it looks more like it went through the dishwasher. That would be another thing to try. Maybe I'll throw a copy of E.T. in the dishwasher and see what happens to it... But, it IS Quadrun. If the label is in that bad a shape, I wonder what the board looks like. -Ian

To those that might have something similar happen to them, let me explain the troubleshooting process. The problem was that some colors, that should have been different, were appearing as the same color - for example, the lower "forest" in Pitfall, and the tree canopies. By modifying a working Atari here (disconnecting pin 5 of the TIA), I was able to recreate the problem. Here's what it looks like: http://www.atariage.com/forums/index.php?a...g&id=127039 (is there any way to re-use attachments in new messages, short of doing this?) He verified that yes, this was what his screen looked like. In case you're wondering, the TIA generates three levels of color signals, and a black and white signal. This is then mixed together with a resistor network to create the composite video signal that gets sent to the RF modulator. With one pin not connected, one of the color brightness levels is missing, so in situations where that bit is used, you lose that information. So, two colors that differ only by the one signal are displayed as the same. So, I had him check for bad connections around pin 5, on the back of the board, between the pin and the chip's socket, etc. This failed to net any improvement, hence the inital thought of a bad TIA. I had him run one more test though... His Atari is a six switch model - not a four switch. This is an important difference, because the six switch models have an extra logic chip - a CD4050. It buffers the seperate TIA signals, as well as the fire button inputs. This chip is NOT present in the four switch models. Atari left it out to save a few cents. It's not particularly necessary in any case. So, I had him bypass the buffer for this particular signal, by connecting pins 11 and 12 on the CD4050. This remedied the video problem, bypassing the faulty buffer. -Ian

Those are just standard TTL logic chips that do the bank switching. I _think_ that it'll be a 7432 and a 74161. This allows the PRG ROM to be somewhat larger than the NES to directly access, and it can swap one chunk of the addressable space to another location in the ROM. The NES can only see 32k of PRG ROM at a time - so if the game is bigger than this, it needs to break this address space up, and swap chunks of data in and out. Some games use simple logic chips to do this, but more complicated games (like Mario 3) use custom mapper chips to handle bank switching. -Ian

I love emulators. They're a lot of fun. But for real gaming, nothing beats the real hardware. So, yeah, at the moment the game cartridge population is a little out of control. Many of them reside in the subsidised housing project (cardboard boxes), but some are forced to wander homeless - huddled in little piles next to the Nintendo and on top of the TV. Plans for an affordable apartment complex (shelves) are underway, construction to begin when I accquire a Round Tuit. -Ian

Are you talking about the metal badge that says "Atari 130XE"? If it fell off completely, than it would be an easy matter to simply coat the backside with some double-sided tape, and stick it back. But if it's still adhered, you don't want to pull it up too much, lest you bend it. Getting glue underneath it would be tricky. I would suggest rubber cement. It's strong enough to hold this sort of thing, and you can just try to get whatever you can under the label with the applicator brush, and press it down - then simply rub off the excess once it's dried. -Ian

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NES games work differently from Atari cartridges. They contain two ROM chips (or a ROM chip and a RAM chip). One ROM chip, the PRG ROM, stores the game program, and the other chip, the CHR ROM, stores the graphic data, or tiles. The Nintendo draws graphics by referencing patterns out of the CHR ROM. This is how the machine is able to move such intricate things around the screen - it need only reference what tile it wants to move, and where to move it. Both ROM chips have seperate address and data busses brought out to the cartridge connector. This is why an NES cartridge has so many pins compared to others - it has two completely seperate ROMs in it. There's also a lockout chip, which uses four pins. If there is a problem with the pins for the lockout chip, the screen will flash, and the power LED will blink once a second. This is the lockout in the console resetting itself, because it hasn't been "unlocked" by the cartridge. If there is a problem with the connection to the PRG ROM, the game won't load - you'll get a blank screen (but it won't flash). If there is a problem with the connection to the CHR ROM, the game usually loads, but the graphics will be messed up. You'll either get lines through the graphics (data bus problem), or objects composed of the wrong tiles (address bus problem). In almost all NES cartridge problems, the culprit is the edge connector fingers being dirty or damaged. Nintendo made pretty good stuff, the soldering and build quality of the boards themselves is very good. Check to ensure that none of the pins are damaged, corroded, scratched or dirty. Some cartridges are just beyond repair. I found a couple that had been "cleaned" with sandpaper. You could kinda get them to work - but then the exposed copper just oxidized again, and it didn't work again. Note that _some_ games (like Top Gun) don't use a CHR ROM, they use a CHR RAM. This serves the same exact purpose, but the software copies graphic data from the PRG ROM into CHR RAM at startup, and then the game can modify the contents as needed. This allows more complicated, varied graphics to be generated - but at a price of decreasing the ROM space available for the game. -Ian

Yeah, I kinda have a sneaking suspicion that the more common failures should be pretty fixable. But having never seen one, I can't say for sure. I posted a "broken Astrocades wanted" note in the Marketplace. I'm really curious about these now. -Ian

I bought an Atari 5200 console from superomni - it arrived in better-than-described condition. The plastic film was even still on the Atari metal strip! And the pile of known broken controllers that came with it wasn't as hopeless as he let on - I got one going good out of the parts. Thanks! -Ian

---_--- DATA_OUT <-|01 16|<- VCC (+5V) DATA_IN ->|02 15|<- GND SEED ->|03 14|<- GND LOCK/KEY ->|04 13|<- GND UNKNOWN2 - |05 12|<- GND CLK ->|06 11|<- GND RESET ->|07 10|-> SLAVE CIC RESET GND ->|08 09|-> /CPU & PPU RESET ------- Here's the pinout. Just cut pin 4 on the chip in the console, and it'll default to key mode. That effectively disables it. You can't remove the chip, because it controls the reset line on the CPU. -Ian

Slightly off topic, but I figured this was an interesting point - and a creative solution by a seller. I recently bought a couple of NES cartrides from a member on another board. He shipped them to me USPS (first class, or Priority, I forget), and I received them last night. These were bare cartridges, but he used a really novel method of packing that was cheap and worked really well... He stacked the four carts on top of each other, and wrapped them in computer paper. Then, he fitted them to the corner of some other box, and scored/folded the cardboard around the pile of carts, and wrapped securely in tape. Every side had at least one layer of cardboard, some two overlapping, and the tape held it securely into a nice tight bundle. The computer paper was really only to protect from abrasion and to keep the carts from getting tape on them (box was taped to the paper in places). It was a bit hard to open because it was such a tight little package and so well taped, but it got here just fine and the cartridges inside were in perfect condition. By making his own little parcel/box like this, he saved money, and provided safe effective packaging for the games. Now, this wouldn't work for boxed games, since those really need to be packaged in a larger, crush-proof package, but still, it's a great way to mail a few carts that would otherwise rattle around in a bubble mailer. -Ian

OK - that's good to know, at least there isn't anything wrong with the console then. I might have to get an S-video cable (or composite) - my other TV has that. This one only has 300 ohm flat pair antenna lead inputs. Ah.. I did not know that. I'll have to check that out - I looked up the manual on AtaiAge, and yes - there is a feature to change the sound volume and save it. I'm really suprised that it has NVRAM for that sort of thing. I'll try that when I get a chance. -Ian

I've heard that these things are difficult to repair... The thing is, I've never owned one. Anyone got a dead Astrocade they'd like to part with, so I can learn how these critters work? -Ian

That is an interesting hack. The original NES connector is a bad design, for sure - but it can work pretty well if you're careful. I replaced the connector in an NES here several months ago with one of those cheap new replacements. It started out really tight, and a bit finnecky, but now that it's "broken in", it fits more loosely, and works much better. To make your connector last longer, you need to: Clean every game. Never put a dirty cart in your Nintendo. Get a gamebit and disassemble the game, and scrub the contacts with alcohol. When you come home from the flea market with new games, clean them first. Don't cheat. The Game Genie will bend the heck out of the pins in the Nintendo. Avoid leaving a cartridge in the Nintendo when you're not using it. The connector works by spring tension, and leaving a game in there for two weeks can't possibly be good for it. Keep the cartridge door closed except when changing games, and take care of your cartridges - don't leave them on the carpeted floor to attract fuzzies. Anything you can do to keep dust out is a good thing. -Ian

I find it hard to believe that these can't be repaired - unless there is a failure of a special custom chip or something. The Astrocade is high on my list of "systems to find one of these days", but I've never acquired one. I can't imagine them being all that hard to fix - the Atari isn't. Do these things have an internal power supply, or use a wall wart? On a side note, if anyone has any dead Astrocades, I'd be interested in them - gotta learn how these things work somehow. -Ian

The "green cart slot problem" affected only very early production six switch models. It was a technical bulliten from Atari because they found these early cartridge slots wore out quickly - and they noted that when Atari service centers received machines for repair with the old connector, they should be replaced. This was fixed very early on - your Vader model will be fine. If you want to clean the cartridge slot, simply take a bit of clean computer paper and fold it over a couple times, until it's about as thick as a circuit board. Cut it to the width of the connector on the end of a game cartridge (like an inch and a half or so), and gently insert the folded edge of the paper into the cartridge slot of your Atari. You'll have to open the little door first - stick a flat blade screwdriver into one of the little notches on either side of the connector, and that will open the door. Press the paper down into the slot, and pull it back out. It'll have a bunch of little lines on it from the dirt coming off the connector fingers. Repeat with clean paper until you don't have any more crud coming off. For very dirty consoles, alcohol can be added to the paper. It's rare that a console really needs to be cleaned, only if you have a large number of games that don't work. And even then, it's usually the game that needs to be cleaned. Your RF noise problem could be due to loose shielding inside the console. Open it up, and check that metal box that surrounds the middle of the board. It should be clipped in tightly. If it's started to rust along the bottom, or was removed before and not properly clipped back in, you might have minor interference. Try pushing on it when the game is on - and see if it changes anything. Remember that the Atari is a very early game console, and the RF connection never was the greatest out there. You're not necessarily going to get a perfect picture in every case, a small amount of noise is common. -Ian

Have you tried cleaning it? Clean the edge connector on the circuit board with isopropyl alcohol. Scrub with a paper towel or cotton swab until you stop getting black gunk coming off. -Ian

Did the game play? I mean, were you able to start a game, and move the joystick around, and see/hear it working? I've seen the opposite problem, where you get picture but no sound. It could be the way the AFC circuit in your TV detects the carrier. Try adjusting the fine tuning knob on the TV, and see if you can get the picture to come in - even if you lose the sound. Since your HDTV is unlikely to have fine tuning - try it on another set. On the Atari's board, there are two controls. One is a potentiometer you can turn with a small flathead screwdriver. This adjusts the color - and won't help you here. The other is a tall (usually red) device - it's a variable inductor that affects the sound tuning. You need to adjust this with a PLASTIC tool (a metal allen key will break it). Adjust it by gently turning the slug back and forth. The only thing I can think of that could cause the problem you're having (assuming the RF modulator in the Atari is good), is that your TV's Automatic Fine Control circuit is locking onto the audio subcarrier, which is slightly off, an thus not picking up the picture properly. Again, this is a guess, since I'm not too familiar with the latest TV sets. Fiddle with the control a bit - you may have to flip up and down between channels as you do this, because you want the TV to lock back onto the signal each time. It's worth a shot... -Ian

I never got "into" the Jaguar like I got into the previous three Atari consoles, but I do have one. I found it at a flea market for $25 two or three years ago, and just had to have it. When I first got it, I played a few games of Cybermorph and Primal Rage, and then let the mighty cat sleep... But yesterday, something got in my head that I had to play it again, so I retrieved it from it's shelf and hooked it up to the TV. A couple oddities that I don't remember. There is a vertical band of odd digital interference in the picture, off to the left side. Also, I had a hard time getting the picture to come in clearly - I tried both channel 3 and 4, and fiddling with the fine tuning knob, and was able to get a slightly better picture on channel 4. I found that the official Jaguar RF switch seems to introduce a fair amount of interference - the one from my Nintendo works much better. Still have that band of noise in the picture though. All the games I tried worked fine - or at least, they seemed to. Except Chekered Flag. There was no sound whatsoever, but the game plays fine. I can't imagine that it's supposed to be like that... The cartridge looks perfectly clean, although I didn't try cleaning it yet. I'll have to try that later. Now I just need to track down some more games for this thing... -Ian

I've had plenty of games shipped to me in bubble mailers with no problems... except... those were cartridge-only games. At first I was skeptical, but they do survive with no problems whatsoever. Carts are sturdy, and when in a bubble mailer, are adequately protected. I was really suprised once, however, when I had purchased like 20 Sega Genesis cartridges, and I came home to find a very large bubble mailer, bashed into a shapeless bag, shoved to the back of my mailbox. When I opened it up and dumped out the cartridges - they were in perfect condition, no damage whatsoever. Now, that's not to say a great big bubble mailer is a good way to mail a pile of loose carts with no packing material whatsoever, but, hey - it worked. But I honestly can't understand the mental state someone would have to be in to ship a boxed game in a bubble mailer. It doesn't make any sense! There's virtually no way that it's going to survive without getting crushed. A cartridge alone is strong, heavy plastic. But the boxes are thin, flimsy cardboard. They need more protection than a bubble mailer. It has nothing to do with video games - it has everything to do with basic, common sense. Any object you ship, be it a video game, a nicknack, whatever, must be adequately protected by it's packaging to survive it's journey though the postal system. Unfortunately, common sense is a bit of a rare commodity these days. Perhaps one could make a business selling common sense on eBay... -Ian