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Urchlay

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About Urchlay

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  1. > When we all die in the coming Mad Max apocalypse, the cockroaches that gain sentience afterwords will probably be playing Donkey Kong on them. And Keith Richards shall be their King, upon his throne of Tupperware...
  2. > what I would like to find is say the Holmes.. but download it all in a zip?? The Holmes archive isn't what I'd really call well-curated or well organized. It has a lot of duplicate files and "cruft", e.g. badly-cracked games whose crack screens require a particular OS revision (XL or 800 rev B) even though the game itself works on any Atari OS. Also a lot of corrupt files, some truncated, some that look like they've been "cooked" by having the ASCII carriage returns removed (or ASCII carriage returns added after every ASCII linefeed byte). Also multiple "versions" of the same game, slightly different binary load file structure, but they end up loading exactly the same code/data into memory. Or, same code/data except for different cracked-by intros. Basically it was someone's Atari 8-bit collection he'd been adding to for years, and at some point he released what he had as a 3 CD set sometime in the late 90s or early 00s... which hasn't been updated since then. Not saying Holmes is utter crap or a waste of space, but I am saying it should be the last place you look for something, if you can't find it elsewhere. These days, 3 CDs isn't that much bandwidth or storage, you could just download the whole thing. I don't know how people do that on Windows or Mac, but I'm sure a lot of people here do (I use wget on Linux, which does exist for Windows AFAIK).
  3. > NO video signal at all Is there audio? Without a drive attached, do you hear the SIO polling "fart" noise? If you hold down Start, do you get the cassette boot buzzer?
  4. Lot of useful suggestions here... > You could probably mod a 2532 EPROM to work, with some remapping of the CS to OE pins (50% chance of it working without needing an inverter.. hmm) Not a 2732? I ask because I actually have some 2732s in a drawer (used to use them for 2600 carts). I think the high rom would have the active high chip select, it would need an inverter like the 2600 does. > quickest 'fix' here is probably to just take an 8K Atari BASIC mask ROM (2364) out of an XE or XL and plug it directly into one of the sockets of this 8K PCB leaving the other empty and it should work Yeah, except I don't wanna break a working machine, plus all my XLs have built in Rev B (ugh). Maybe Best/B&C can sell me one. > you could directly modify this 8K PCB to take a single more common 2764 EPROM That looks like something I could do, and I've likely got 2764s lying around (or can order some, they're still pretty common I think). I know I've got at least one 27256 (also 28 pins), used it for a 2600 multicart that's still in the closet somewhere. So a 2364 mask ROM is 24 pins, but a 2764 EPROM is 28. Was there ever such an animal as a 24-pin 8K EPROM (2564 maybe)? My old EPROM programmer could definitely handle the old chips, it looks like late 70s tech, an RS232 GTek. Really the deal here is, I'm willing to spend time & effort to fix this old cart, but not very much money. I don't absolutely *need* it working, I only have one machine without built-in BASIC and I have a working BASIC cart for it. The dead BASIC cart has some sentimental value, that's about all. Also I got a BASIC XL cart that works nicely, just in case :)
  5. K (Binary Save) option from DOS 2.5 menu. I have an old burner but haven't yet found its power supply or the 9-to-25 pin RS232 cable it needs (minor miracle that I found the burner actually, I'm not what you'd call organized). Not on this board. I didn't figure this out myself (credit goes to joe_z on IRC, aka "Joey Z" on AA I think). The way this board works is, one ROM has an active high chip select, and the other has active low. The 2 chip selects are connected together, and also connected to the A12 pin on the cart port. So when A12 is low, the low ROM gets selected, regardless of which physical socket it's in. When I dump the working ROM, I get an identical file regardless of which socket the ROM is plugged into: the lower 4K is the BASIC code and the rest (if I save 8K) is all $FF. This makes sense in another way: if there were high and low sockets, there would have to be a chip or at least some other components on the board to select between them based on A12. But all this board has is the 2 sockets and the filter cap, no other components. I dunno why I'm going into such detail now, except maybe that this info will someday help someone else. One of my ROMs is fried for sure, so this cart won't be fixed unless I can find a replacement somewhere.
  6. Edited. Originally said: ...But I was mistaken: one of the ROM chips causes greenscreen no matter which socket it's in, and the other one allows booting no matter which socket it's in. From what I can tell, the 2 sockets are electrically identical: the pins are wired 1-to-1, 2-to-2, etc for all 24 pins. So if both ROMs were working, it wouldn't matter if I swapped them. Since one of the ROMs causes greenscreen no matter which socket it's in, I have to assume that one is bad, maybe internally shorted so it shorts the address/data buses. I went ahead and dumped the one ROM that works. It matches the bottom 4K of a BASIC revision A dump (NOT rev C as the sticker on the front claims).
  7. Heh. I assumed that too. Turns out I'm dumb and wrong. When it's plugged in the right way, chips sockets facing the back of the Atari, the bare board doesn't crash the machine. It boots to self-test, and the memory test shows only 40K of RAM available. You have solved the mystery, and I now have doubts about my own brain... So it looks like the board is actually OK, and the ROMs are fried. More specifically, only one is fried (I get self-test when the left ROM only is in, and greenscreen with the right one only). These ROMs aren't pin-compatible with 27xx series EPROMs I don't think, and there's not room in the cart case for one of the adaptors, so I guess the cart is permanently dead. Maybe I can reuse the shell for one of the cart boards the AA store sells... I even think I know what killed the ROM: the little springloaded wire that puts pressure on the cart shell's lid was out of place, and probably touching the board somewhere.
  8. I'd gotten that far before posting it here... the Atari behaves the same with this board plugged in, whether the roms are in it or not (greenscreen of death, no speaker pop). If I can fix the board, the roms still might be bad, but bad roms should cause the Atari to crash *after* the sceen turns black and the speaker pops (the OS zeroes all the HW registers before it inits/runs the cart). At least, if the chips work but the contents are scrambled. If the roms have died with an internal short, I might get symptoms like I'm getting... but then the rom-less bare board wouldn't cause the same thing. I'm just at a loss for what the fault in the board might be. Thought it might be the filter cap, removing it didn't change anything. Thought there might be shorted lines on the edge connector, but there aren't (except Vcc and RD5 as expected). The sockets are connected in parallel, pin N on the left socket is connected to the same pin on the right socket. At this point I'm wondering if maybe there's some kinda micro-fine crack in a trace, so it reads connected with my cheap meter but acts like a capacitor when it's in the Atari. In other words I'm grasping at straws...
  9. I'm definitely not a photographer, but... Front Back You can see the filter cap's no longer connected, I did that last night. I checked all the pins on the card edge connector last night, no pin is shorted to any other pin, except vcc and rd5 (board's made that way). Also I checked all the pins on both sockets, the two sockets are in parallel: pin X on one socket is connected to pin X on the other one. Looks like the two ROMs have different part numbers because one of them uses active-low chip select or output enable, and the other uses active high. That way the top address line can be connected to both chips without using an inverter or such. I'm about out of ideas. Someone suggested using an eprom burner to dump the roms, which I might be able to do, but the fact that the bare board causes the Atari to crash means the roms aren't the problem (or, not the only problem). Yet I can't find any shorted pins.
  10. Not familiar with the story... was the released Gyruss game based on this code, or was it a completely different implementation? Atarimania doesn't list an author for the Gyruss that got released...
  11. So I've got an old BASIC cartridge, CXL4002 with silver label. Had it since maybe '87, and it used to work. Now it doesn't: Powering up with the cart plugged in causes the Atari to come up in "green screen of death" mode. No "pop" from the audio as I normally hear when the OS clears the POKEY regs, and the Reset button doesn't do anything. It's acting exactly the same as if I e.g. pulled the OS ROM or the RAM from the motherboard. Cleaning the contacts didn't help. I tried the cart on 3 different (working) machines before I took it apart. The rest of my testing (see below) was all done on an 800XL that has no problems I'm aware of. The inside of the cart looks fine, no dust/dirt, no burnt traces or obvious bad solder joints, no visible cracks. This cart's got 2 socketed masked ROMs (or maybe they're PROMs? no erase window anyway). The part numbers are different: one is CO14502 and 8226, the other is CO12402 and 8223CCP. I was honestly expecting EPROMs when I took it apart: it came from a hardware hacker, had a hand-labelled "Rev C" sticker on it. I've been told by a couple of IRC users whose hardware knowledge is greater than mine, that if I remove the ROMs and power up with the board plugged in, the Atari should come up in self-test with only 40K of RAM visible. Can anyone actually confirm this, from experience? (I have no other socketed carts to try it with) What actually happens when I remove the ROMs and plug in the board is the same thing as with the ROMs in place: greenscreen, no pop, etc. The only component on this board other than the ROM sockets is a little filter capacitor that's wired between Vcc and ground. Someone recommended I lift a leg of that, but it didn't make any difference. Something else I tried: my other carts (which all work BTW) cause the Atari to reboot when I insert them with the power on. So I tried it with the bad BASIC cart, sitting at the self-test menu after booting with Option held down. And it crashes the Atari with garbage like you get from a bad display list. Pressing Reset after than causes the "green screen of death", except the shade of green is the self-test screen's background color (a bit brighter than the powerup greenscreen). I'm thinking this is a really low-level problem: like, maybe a couple of the address and/or data lines have shorted together. I don't have any way to test the ROMs in a different cart board (my other carts all have soldered in ROMs, no sockets), but I'm thinking the board itself is the problem. Currently checking continuity between every pair of pins on the cart's connector to see if any are shorted. Am I right in thinking that shorted address/data pins could cause exactly the symptoms I'm seeing? An open (unconnected) data or address pin shouldn't cause "instant death" should it? (I mean the OS should still pop the speaker before it inits the cart, right?) Can anyone think of anything else I should check?
  12. Rockball at least contains code that overwrites parts of itself if it's run from RAM.
  13. Not gonna touch the debate, but here's my take on using a 400: If your main interest is games, there are lots of cartridge games that work on a 400, without expanding the memory. Star Raiders for instance. Also Defender, Pac-Man, Centipede, Super Breakout, Donkey Kong... Some of the games do use the keyboard, but not heavily. The membrane is fine for pressing the space bar to set off a smart bomb or H to engage the hyperwarp engines... If you're trying to learn BASIC, a 400 with the abovementioned $5 BASIC cartridge might be a good starter kit... a lot of us started out that way and the keyboard and lack of RAM didn't stop us from learning. However, I can't recommend using a tape drive. Even when they're in 100% working order (and most aren't due to belt rot!), they're just too slow. At some point you'll want a disk drive (real or otherwise) to save your BASIC code... and that pretty much means you want at least 32K of RAM, since the DOS loads from disk & takes up most of the memory in a 16K machine. If you're having to upgrade the RAM anyway, might as well do 48K. I had a 48K 400 for a few years (after getting rid of the original 16K 400 I started with). I enjoyed using it to play disk-based games, but didn't do much typing on it: sitting next to it was an 800XL, so I used that for coding and word processing and BBSing and such. Would I have been happy with a 48K 400 as my only Atari? Hard to say, but I definitely would have used it as much as I did the 800XL. Of course the better solution for you if you decide you really need 48K and don't want to do any mods/upgrades, would be to buy an 800. No idea what they go for these days, maybe get the 400 for now and patiently await an 800 at a price you can afford later? I'd recommend an 800XL, but you've made it clear enough that you don't like the XL or XE machines... too bad, because an 800XL makes the best starter Atari IMO: built-in BASIC, 64K, decent keyboard, and the [email protected]%#$^@#%^ keyclick sound is routed to the regular audio output so you can turn it down when it gets on your nerves (on 400/800, you have to disassemble the machine and unplug the internal speaker, or install a switch to turn the keyclick on/off). About the TI-99: I won't say anything about whether or not you should get one insted of an Atari (I'm biased, I've had an Atari for decades). I will note that if you decide to add an original TI-made floppy drive to a TI-99, you'll be giving up a good chunk of desk space. The peripheral expansion box is huge and heavy (seems solidly built at least). Using a cassette for storage on a TI is just as miserable as it is on Atari.
  14. Ages ago I had a 400 that had problems with the cartridge port, it turned out to be the little DOM sticker Atari put under the lid to the cart port. Over time the adhesive lost its sticky, and it fell into the cart port & blocked one or more of the pins. If you shine a light in there and see the same thing, you can do what I did: carefully remove the sticker with tweezers, then clean the cart port by spraying QD or Deoxit [*] in there & inserting/removing a cart repeatedly. [*] BITD, I used Radio Shack Color TV Tuner Cleaner. But I doubt that's still available.
  15. Each country's got one or more DATA lines. First line has the country name, capital name, and a list of plot/drawto X/Y coordinates expressed as character data. The last pair is either 2 ctrl-A's (meaning "no more data") or else 2 inverse zeroes (meaning there's another string of data on the next line, I guess for countries with discontinous territory). Also the very first data line, last number, is the total number of countries. If you were just unifying the former East/West Germanies, you'd decrease it by one. For countries that have changed names and/or capitals, but kept the same borders, you just change the name/capital data. For countries that merged or split or otherwise changed shape, you gotta draw out the shape and encode it as ATASCII byte pairs (fiddly work).
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