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Alphasys

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About Alphasys

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    Chopper Commander
  • Birthday 07/29/1969

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  1. Alphasys

    Alphasys

  2. Strange enough, I can see the pictures you "reposted" without any problems. Maybe I just tried to include them in the wrong manner...? I used to call it my Atari 384 XLE... (320k XE + 64k XL)
  3. I guess you missed the point I was trying to make... Ofcourse you can "try" to compare the two, but it's like comparing an apple to an orange, since they are both fruits... In the end, it is still just "a matter of taste" which one you find most compelling. So subjective...
  4. You may want to have a look on facebook. Freddy Offenga (aka Frankenstein of the High-Tech Team) is very busy with the Atari Preservation Project, that actually does what you want with Espionage. You can find this at https://www.facebook.com/AtariPreservationCollective and I'm sure that he'll be able to help here.
  5. Well, my two cents to this topic... I really don't think they can be compared fairly. Yes, they are both 6502-based, yes they had titles in common, yes they can do similar things, from a black-box point of view, yes they both have "intelligent" diskdrives, but then again... The Atari actually has 2 processors and the CPU isn't even the one that "dictates". Commodore only has the one 6510. Clockspeeds are to far apart to be compared significantly. Any comparison here should be about how many clockcycles it takes to produce a certain effect. Display technology is incomparable. While the C64 employs a similar tactic as MSX/Colecovision, there's just nothing like the Atari's Display list and GTIA colormapping. This is also very visible in the "sprite" department. Where the Atari uses a "vertical bar" approach, the Commodore uses "cells" that can be moved anywhere. Sound reproduction is also incomparable. While the Atari has to "constantly" adjust pokey's registers to make an interesting waveform, the SID has this built in. Serial IO is done by Pokey and PIA on the Atari, while the C64 has this built into the 6510 and uses its CIA for interrupts and command lines. So if you look at the designs, the Atari is "primarily" built to create stunning graphics, yet putting sound generation in a lower priority category, where the Commodore 64 has (comparatively) toned the graphics down a little, yet giving a better soundscape. Just by the fact that they are from the same "era" and they share many titles, doesn't mean you can really compare the two. Well, that's my opinion anyway.
  6. A PAL model will be a little slower in experience, yes. A PAL machine will "do" a vertical blank interrupt every 50th of a second, while NTSC does it every 60th of a second. However, because the PAL machine works in this way, there are MORE clockcycles available WITHIN the VBI routine. This the main reason why all NTSC software will run on a PAL machine, but not the other way around. A PAL machine just has "more time" to do its VBI stuff. If this is used, an NTSC machine would call for a new VBI before the previous one is "done", causing the computer to lock up. The same applies to Display-list Interrupts, to some degree, since the PAL Antic does it's datafetching a little slower, there's a few clockcycles "extra" that can be used. Depending on the time between DLI's, this might cause a lockup, or weird artifacting on screen, causing flicker or other weirdness. You can probably understand that, if a DLI switches between colors or character sets, and the Antic starts datafetching before the DLI finishes this task... Heck of a mess on screen. Since the XL/XE line was/is so popular in europe, most of the newer software was/is developed there and this problem really is a problem.
  7. Hi applekevin, Oh wow, that is a lot of questions indeed. Some are straightforward, others a bit ambiguous or a matter of taste, but I'll try to answer what I can. PART 1: Models The 800XL is indeed the "de facto" standard, but... The 130XE has the advantage of a sleeker design, 64kB of extra memory, with the FREDDIE chip in it. This makes memory expansions somewhat easier to build in. However, the 130XE does not have an expansion port (used for some hardware, like some older IDE interfaces and the 850 parallel bus expansion module) but instead it reuses the cartridge port, with an "extra" port, where sadly not ALL the signals available on the XL's expansion port are put. All being said, I prefer the keyboard of the XL series, since they're more durable than the XE's. This is really a pro/con thing on all sides. The cartridge ports on ALL Atari 8-bit home computers are the same. Same pinning, same size, same working, however, not all Atari 8-bit home computers are 100% compatible, due to hardware changes and specially, the OS rom. The 800's expansion ports are there for memory upgrades, up to 48kB of RAM, and it has 2 cartridge ports, although the "Right" cartridge ports only was used for a handful of things. Notable: Monkey Wrench. PART 2: Upgrades The VBXE is nice and fun, but so far there's not that much software for it yet, and if you're looking to play the classics, I don't think it's a needed expansion. In regards to RGB output etc... Google "vbxe atari" and look at the specs. S-video mod? Unless you'd buy an Atari 400, there's a composite signal coming from the monitor port, so what would you need S-video for then? Got no answer, try that website. I've really never needed to mod any of my Atari's to s-video, so I can't answer this either. As for RAM upgrades, there are a LOT of options there, some easier than others, some will only work with some models. If you're NOT into programming, get a 130XE and you can pretty much run anything worthwhile. There used to be several stereo mods. The most common one uses the adressing space of the original pokey, just shifted up 16 bytes. This has sort of become the standard. Since the Atari gets its color clock from the same source as the CPU, there's not much you can do to "accelerate" the 6502 without a lot of hassle. There is one expansion I know of that employs a 65816, which basicly is a 16 bits CPU, but has a "native 6502" mode, and as such can work with the Atari. Speedwise though, you don't want to mess too much with it, since it'll quickly make games unplayable. The 32-in-1 OS is a replacement eprom of 512kB, which has 32 16kB OS images burned into. (I already had trouble choosing 10 for my own expansion.) The OS is like the PC's BIOS, and is in ROM. When a diskdrive is attached, the needed DOS is loaded from disk. Some OS-es change the "selftest" routines into a monitor program, for machinelanguage programmers. Other OS-es can fix the compatibility issue between 800 and XL/XE machines, so older software will run on the XL/XE. Yet another class adds completely new functions, like a 80 column textmode. (Well, it's emulated.) As far as I can remember the Multi-IO, this is more a thing if you have, for example, 3 computers, but only 1 diskdrive. All peripherals are chained to eachother in a normal setup, where usually the printer is the last in the line. PART 3: Peripherals Can't say anything about SIO2SD and Nuxx SDrive, beside that they indeed seem to accomplish similiar goals. In regards to CF/IDE adapters... SIDE2. It's the newest and is well supported. Older, more complicated systems, like the Black Box, also work well, but are "true IDE" so no thumbdrive, true IDE harddisks. Hard to find, expensive and more error-prone though. I think it'll only handle MFM drives even, which are now really hard to find. I have no information about networking/ethernet/internet connections, besides that emulators can hook up to the net over a kind of telnet connection. I've yet to see a 9600baud modem work with an Atari. As far as I know, there were only 2 modems for the Atari, both hooked up via the 850 interface (which is in dire need of the XL's expansion port, aswell as the SIO) and were 300baud or 1200baud. It might be working with 9600baud somehow, but I've never seen it yet. PART 4: Miscellaneous Oh, carts... Phew... There are SO MANY TYPES, this is a really hard one to answer... A simple cartridge program can easily be "converted" to disk, but that doesn't mean it can easily go the other way around. It's all to do with memory mapping. Some cartridges have mapped memory in themselves too, which makes it even harder. Not everything will work with everything all the time. There are always exceptions to the rules. Sorry, this is one confusing part that's just not really explainable unless I go deep into hardware. Trackball, mouse, touch tablet/Koala pad, lightpen... Definitly cool accessories. In the way of peripherals, I've made my fair share of hardware, and most of it is unique to my machine. You certainly already mentioned the available and well known stuff. A diskdrive is still a must in my opinion, although you could also look at SIO2PC solutions with appropriate software for the PC, which in turn then emulates up to 8 (or 9?) diskdrives. If you have a diskdrive, there are also "core replacement upgrades" for that, that make it faster, better, stronger and make it sing in high pitched voices. Happy 1050, US doubler, Speedy 1050, etc etc. Quite a lot to choose from there. One thing I can certainly tell you: Get a PAL version Atari. (Just saying, cause I have no idea where you live.) NTSC Atari's work with different clock speeds and a lot of software will just plainly NOT WORK on an NTSC machine.
  8. Thanks flashjazzcat. Looks like the UK rules again. Makes me wonder what's different there that you can actually see them, while I can't even see them myself...
  9. Oh wow... I can relate to these stories, because some of my friends had this problem constantly. I only started going online after I had my own PC in my own house. 28.8kbaud. Top of the line at that time. Ofcourse it only took something like 2 months before 36.6kbaud came, and then cable within a year. I hated the dial-up system... The phone bills I got, still hurts when I think back at those. (And I think that phone company still hates me.) The fun only started with monthly flat-fee, always on-line, cable internet.
  10. For the love of the forum gods, I decided to just stick the zipfile with the pics right here, as an attachment. If that won't work either, I'm at a total loss... PhotosAtariMonsterTower.zip
  11. Hi Jose, Gosh, now that's odd. The site where the pics are on, is my own. I've uploaded them there myself, and those links go directly to the pictures, no page or whatever. Maybe my site got put into some weird blocklist again, wouldn't be the first time. I wonder what way I could use to get the pics in-line, even if it's in multiple posts. Although, knowing forum users, they'll start yacking as soon as post #1 would be there, making a mess.
  12. Yeah, noticed that too after I first hit the "Post" button. I've updated the post, hoping this will do. Inline pics would have been so much neater.
  13. After posting this with in-line pictures, I have noticed that the pictures are not displayed, but are put in as "Posted Image" links that don't work for me, so I've updated this post with direct links to the pictures next to these disfunct ones. If you would like to see ALL the pictures I made of this, go to http://www.alphasys.nl/fotos/index.php?map=3&picture=DSC03264.JPG and click on the links under the word "Plaatjes", or download a ZIP file with all of them at http://www.alphasys.nl/downloads/PhotosAtariMonsterTower.zip (2.274.878 bytes). Hello 8-bit fans! It's been a while ago, that I'd asked if anyone would be interested to see photo's with an explanation of my "Atari in a big-tower". There were some. Now I actually have a decent enough camera and have the thing in the house anyways, instead of storage, it was about time to do it. So here goes: Exterior view. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03264.JPG Front view, lots of switches, buttons and 7-segment displays. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03266.JPG Rear view, most connectors have a sticker next to them with their purpose, but I had more ports than stickers. Quite hard to read on this photo though. You can already see there's more going on than on a "standard" Atari XL/XE machine though. So let's open this thing up... I hope you're sitting down... http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03269.JPG Interior view when the cover is off. The crazyness starts to become apparent. That's a lot of wires. In the back you can see the 130XE board (behind the "harddrive mount") and that ugly grey thing in front is the bottom plate of a 600XL. In the top-part, you'll recognise the 1050 Diskdrive with its own PCB below that. (Which was a delicate puzzle to get in there. I'm glad I could fit it in eventually.) The 600XL is held in place only by the powerconnector and monitor plug, that have been tie-rapped to the "harddrive mount". I'll unplug those and let it drop out. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03272.JPG As you can see, it's not quite "original" anymore. The game-ports are replaced by wires, aswell as the keyboard "connector". These have all been externalised and made available on the backpanel, in the expansion area. (The big blue connector near the bottom of the case is for keyboard, with gameport A next to it. Gameport B is below that on it's own "strip".) Observant hardwarians will also notice it has 64kB RAM instead of the standard 16kB, and I've done something to the PIA aswell. That rainbow of wires is hooked up to Port A and B of a piggybacked PIA, actually. This is part of the internal "Eightlink". http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03267.JPG The housing of the 600XL still came in very handy though. It became my external keyboard. There's about 6 feet/2 meters of flatcable between the computer and keyboard now. Yes, that works fine, never had any weird behaviour with it. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03268.JPG Interior of the keyboard. I just hooked up the lines, in order, to a connector that's now part of the backplane of the 600XL housing. The cable is thus detachable. This keyboard now works for BOTH computers. It was a bit of a puzzle, but I wired both computer-side connectors up in the same way. Now get me right, the 130XE does NOT have the same order of connections on the PCB side, but the keyboard matrix itself is (ofcourse) identical, so this was a viable solution. And I was glad too, since the keyboard of my 130XE had become so corroded that it would not work anymore. If you're interested in it, I still have the "translation table" for these keyboards in my "little blue book of atari knowledge". I guess I'll continue with the main machine part now, the 130XE board. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03278.JPG It's hard to show the thing properly, but I'll get to other parts in subsquent photos. As you can see, I also exported the keyboard (bundle of red wires) and gameports (2 bundles of black wires) to an external connector. I used connectors to plug into the gameports on the board this time, since that was easier when I had to take the board out. You may also notice the pokey, with a small perfboard on top. Let me zoom in on that. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03296.JPG I know it's ugly, but yes, this is the stereo-expansion. The pokey on top is missing a lot of pins, because it was gutted from a broken Atari by someone with "sausagefingers" and then sent to me by mail in disfunct packaging. Even pin 37 was completely severed. After some careful filing, I managed to expose enough of it to solder a connection to that, but it would remain a weak spot, so I glued the perfboard on top to hold the stuff in place, while it also gave me a place to put the pull-up resistor. Luckily, the other severed pins are for the keyboard matrix and SIO stuff, which were not needed. Both the Pokey's have also been decoupled and linked to the 2 RCA outputs on the backside, so I can hook up stereo to a stereo directly, while the second pokey is also linked up to the amplifier that drives the monitor output, so I can still hear all 8 channels out of the TV if I would choose so. Right behind the pokey's, you see an awful mess of black, red and multicolored wires. That is what actually prompted me to start this project. What you see there are actually 4 PIA's on top of eachother. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03297.JPG A view of the other side. PIA's with chip-sockets in between. Besides the "original" function, there's one for the internal "Eightlink", one for an external "Eightlink" and I can't remember what I was going to use the last one for. (It's been over 20 years...) Possibly a Stereo Covox thing, since I still had ideas about making a stereo x 8-bit sampler which would have been useless without proper playback device. You can probably understand that this "pile" of PIA's would not fit in the original 130XE housing anymore. The case was also becoming quite ugly, since I had drilled so many holes in it for switches and LED's, which are now on the front panel. I already had replaced the foil of the keyboard with a PCB version, which I had made with the foil as a masking template, but even that one was starting to fail. So, what else is there on the main board... Well, there's the memory expansion, for one thing. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03290.JPG This is one of the "of the shelf" expansion that's in here... A 256kB RAM expansion, which "replaces" the 64kB of the normal 130XE bankswitchable RAM. I didn't make this myself, just installed it myself. I did however make a slight change to it: Hardwarians will know that the dynamic RAM inside the Atari is refreshed by something called "CAS-only refreshing". The actual reading/writing to it, requires another line called "RAS". I noticed that the expansion installation instructions required me to cut the line for the RAS signal, so the "normal" 64kB would not be read from or written to, but instead this line would now adress the 256kB expansion. That meant that this "original" 64kB would still be refreshed, but not accessible. What a shame! What I did was actually very simple: I took this RAS line, and hooked it up to a switch, that would either connect it to the 256kB, or the "original" 64kB. That gave me a hot-switchable ram-expansion! By the flick of a switch, I could use an "Original 130XE" with 128kB total, or "turn on" the expansion and have 320kB adressable. (So, that's one of the 7 flipswitches explained.) Best thing is, that both these "ramdisks" are usable, will remain refreshed and can be switched between. I used this a lot in conjunction with the Qmeg OS, where I would have my "bootable" 256kB ramdisk filled with my development programs, and when I wanted to test my program, I would save it to disk, switch the "ramdisk" to 64kB mode, reboot and test. Then after testing I would just switch back to the 256kB ramdisk, and reboot my development environment from there, with all its stuff still intact. Now I mention Qmeg... Look here: http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03299.JPG In this picture you see two chips. The one with the red sticker is the BASIC rom, which I also hooked up to a switch to be able to turn it off without holding "option". The other one has perfboard on it again. This is not your bogstandard OS ROM. It's actually a 256kB EPROM, where I used 160kB to stick in 10 OS versions. The perfboard on top is hooked up to the 4 "extra" adress lines on this chip, and connects it to one of the thumbwheels on the front panel. This neat little device has 10 "states" that you can select by pushing the +/- buttons on it, while it indicates its state by the number shown in the little viewport between those. Besides the "standard" OS, I have the forementioned Qmeg OS in there, together with several "translator" type OS-es, and some special purpose OS-es. Most notable: Omnimon and Supermon for 800 compatibility, Omniview for 80 column textmode things. I know, I could have fit 16 in there, but I already struggled to choose 10 and it fit the thumbwheel. I already mentioned one "off the shelf" expansion. There is another one in the tower, but for understandable reasons, I can't make pictures of that... It's in the 1050 diskdrive, under the shielding. This little piece of splendor is called "Mini Speedy 1050 DS" and is Germany's answer to the well known "Happy" extension. It's fast, it's programmable and it sort-of has 2 "bootdisks" built in. Yep, another switch was needed. In the "up" position, booting the computer with the drive bay open, will boot up Bibo-Dos, which is Atari Dos 2/2.5 compatible, and can also handle Double Density disks. In the "down" position, this same manner of booting would load the High-Speed Sector copier. There are 2 "downsides" with the diskdrive though, which I have solved with the 2 (black) push buttons on the front panel and the following nugget of electronics... http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03282.JPG This ugly perfboard holds 2 monostable timers (the NE 555's) and a set of J/K flipflops. The timers are used to "debounce" the buttons, which would otherwise not be very reliable. Each button will toggle a J/K flipflop, while the circuit also makes sure that the features it will switch, are always in the "default" mode when it gets power. The first button/feature is easy to understand... It's write protection. As soon as you turn on the stuff, the disk is safe, and there's no need for silly stickers that only get lost inside the drive over time. One push of the button, the LED above it turns red, and you can write to your disks, even when there's no notch on the side. The other button handles a Speedy feature. It basicly "turns off" the high-speed transfer mode. Some games just don't like it when it's loaded faster than it expects, and that makes it fail. But still, those are few, so I've set the "default" to high-speed. Now there's still more "perfboard" in this thing... Some of you may already have noticed something going on in the bottom. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03283.JPG Not a great picture, so I'll take it out and show it better. http://www.alphasys.nl/fotos/plaatjes/AtariMonsterTower/DSC03285.JPG Enigmatic? Well, this is a little driver board for the 7-segment displays and a selector. One display's the "currently adressed memorybank" of the Ramdisk in hexadecimal. The others were planned for other indicators, and you may notice the label "DWS 2 Romdisk" on one of the cables. Now we get into painful territory, since this marks the state it's been in for 20 years... Stuff was planned here. Nice stuff. Fun stuff. But I doubt I'll ever make it happen... Because, well, the computer is dead. Working with hardware is a lot of fun, but its also prone to mistakes. Not that I've ever broken anything with my soldering iron, or any of my expansions caused a cascade failure... It was the powersupply. In one lapse of memory, while I was about to give my brother an opportunity to play Kennedy Approach among other games, I made a STUPID and UNFORGIVABLE mistake... I hooked up the 12V line to the computer, instead of the 5V one... The machine will never work again. This Romdisk thing never came to be, although it was a sound idea, based on the way Qmeg "handles" the ramdisk to make it bootable, and the way this "RAS/CAS" selection works. The idea was to decouple the RAS line from all "extra" RAM and instead make the system adress a 256kB Eprom, filled with data from 2 bootdisks in single density in the manner that Qmeg reads it. The "DWS" refers to the second thumbwheel I have in the front panel. And yes, I was planning to add 10 of these 256kB Eproms, giving me a whole lot of programs I could have loaded "on the fly". Basically 20 SD disks worth of software. Well, that's the end of this long, but hopefully interesting post. Maybe some of you got a few ideas from this.
  14. The "routine" to sample at 8-bits resolution with or without stereo, would probably fit in the space used by existing software, since there's no need for any shifting and adding. But you would need a program that is already fit to use a ram expansion. Keep in mind though, that when you need to switch banks, this will take more cycles, that may produce clicks unless properly timed in the program. The same will apply to playback programs.
  15. Be my guest. Since I designed them, I'm the only one who can really say "It's Public Domain now". I doubt you can get better quality out of it though, since I already took all "hi-fi" precautions. (Using an opamp just to stabilise the reference voltage, for example.) The PCB was designed with the housing in mind, so you might be able to improve something there perhaps. Specially the places where a signal goes from one side to another, can definitely be cleaner. I've sampled tracks as diverse as possible to test the thing. 80's & 90's pop music, classical music, speech, hardrock, pure sine/triangle/sawtooth waves ranging from 20Hz-22kHz off a Dolby test CD. For the resolution (4-bits) it sounded pretty darn good, but ofcourse it has a little trouble rendering low volume music, like the start of Ravel's Bolero. Gets a bit noisy then.
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