Larry

Hi Steve- Thanks for the code. The concept looks very usable! I've always enjoyed little "puzzles" like this rotor thing, and it's interesting how many different ways they can be solved! -Larry

Do you have any details of your upgrades (44256 and SIMM)? Wiring diagram or such? -Larry

Thanks to all for the suggestions. Yes, using indexes looks feasible to me. There is a lot of info on the web about the Enigma, but the info at Wikipedia is among the very best that I've seen. I got interested in the Enigma several years ago when I saw a documentary on Public Television (or maybe the History Channel) about it. Since then, I've collected quite a bit of info. -Larry

I have started working again on an old project of mine -- an Atari simulator version of the WWII Enigma cipher machine. I'm using BASIC XL, but as I see it now, porting it to Turbo Basic XL would not be much of an issue after completion of this version. Here's my problem/question: My Enigma "machine" has 3 "rotors," each with 26 alpha characters, and each has it's own unique "wiring" that puts its alphabet in a particular order. When an input key is pressed, then rotor #1 indexes one position to pick up the next letter on the rotor. After rotor #1 has made one full revolution, then rotor #2 indexes one position. Then after rotor #2 has made one full revolution, rotor #3 indexes one position. (Much like a car's odometer.) Of course, there is much more to the "machine," but this indexing is a crucial part of getting it encoding/decoding correctly. This indexing is a challenge -- I need a fast way to index that hopefully won't get too cumbersome. My initial solution is to have the "rotor" as a regular string of 26 characters and then use a small subroutine to "index" the string by re-writing it, temporarily saving the first character in the string and moving the next 25 characters up one position, and then taking the saved (first) character and making it character #26. Using strings, this is pretty quick. But there are surely other ways to do this, and hopefully, better ones. I could use pointers, but I *think* that would get quite convoluted. A perhaps simpler way would be to use a large string made up of repeating segments of the 26-character "rotor". Then to index, I would just "move" the rotor (substring) up one position in the large string. That way, I would only have to reset my substring when I ran out of characters (infrequently). Any suggestions for my Enigma enigma? -Larry

I thought someone more familiar with SDX might answer this (hopefully they still will!), as I'm not primarily an SDX user. But here goes... If I use my SDX cart (4.22) with the regular XL/XE OS and APE, I get the regular Sparta "UltraSpeed" (not quite as fast). If I use it with my Black Box (so the BB drivers are present) then I get 3X. Of course, in DD, it won't sound quite as fast in either case. Hope that helps. -Larry

I read through some of the threads at the Atarimax forums, and evidently that is a common problem with those adapters. But SIO2PC does work with the adapter? In that case, did you try the DOS version of APE? Much less full-featured, but still more useful than SIO2PC (IMO). I know nothing about Vista, but I believe I remember that it runs under XP in the "DOS" window. Here's a thread that talks about the subject of USB to 232 adapters: http://www.atarimax.com/flashcart/forum/viewtopic.php?t=447 -Larry

Hi Bryan- Yes, that makes sense, and I had not thought of using the Dremel. I have one -- which tool do you find best to use? -Larry

Is this the Forbidden Forest, Aztec Challenge, Caverns of Khafka compilation of files + loader? -Larry

I've found a nice case for my SIO2SD board, but I need to cut a rectangular opening in the cover for the LCD screen, five somewhat closely-spaced holes for the keys, and a slot for the SD card for "quick change." I have a drill press which should make the holes easier to locate and drill properly, but I've never done any "precision" cutting in plastic before. I also have a regular sheet-metal/plastic "nibbler" hand tool. Aside from "measure twice, cut once" , can anyone offer some tips for this surgery? -Larry

APE won't run with your converter? I'm asking because APE (for Windows) has sooo many more features than original SIO2PC. -Larry

Hi Larry, SpartaDOS needs the MyIDE OS eprom inside your Atari 8bit computer. It does not matter what kinds of MyIDE interface card you're using as long you did replace your Atari OS rom with some kind of MyIDE Eprom. If you don't have a MyIDE Eprom inside your atari: BeWe DOS is still a great choice, because it is Sparta Compatible. Good luck! Marius Hi Marius- Thanks for the info -- I'll give it a try. My XE MyIDE internal interface uses 4.3I. -Larry

From my perspective, if one uses APE or similar system, there is no reason not to use a capture card to provide a (windowed) display on the PC. Why not use one display for both systems? At the present time, only *very* high-end capture cards have HDMI inputs, and none that I know of have actual component inputs. I'm not sure about "combo" PC/TV flat panel displays -- they may well have component inputs. The accelerator (system) that I refer to was produced by a company called "Multiplex Technology" in Brea, CA. (At least that's what my notes from the World of Atari '98 in 'Vegas say.) I saw it, watched it run, etc. at the show. I was never able to contact the company, and believe me, I tried! It was in a custom case that had a built-in Black Box, and the accelerator ran at (IIRC) 7.X MHz *outside* of the base 64K, but 1.79 inside the base 64K. This system was supposedly marketed to cable TV companies that used the "Atari" for character generator/text displays (menus, etc.) The accelerator portion sounds quite similar to the Warp 4 accelerator that is still under development. There are more threads here about the accelerators. -Larry

Does Sparta require the Internal or External Rom (or just any MyIDE ROM as opposed to the RAM OS)? -Larry

In a perfect world... I'm not much much of a game player, so I lean to the 80-column. 40/80 column, ability to do multi-colored text (e.g. IBM, and "that other" home computer), and compatible with a "soon-to-be-released?" accelerator. (My hope springs eternal...) In a less-than perfect world... 40/80 really nice columns, compatible with the soon-to-be-released? accelerator. How about using this with PC capture cards? 80-column color might be out at this time, but capture cards with HDMI inputs are on the horizon, and I'd settle for 80-column mono. What fries me about the accelerator issue is that this was commercially produced for an Atari work-alike in the 90's. It still eludes us, but perhaps is getting closer? -Larry

Thought of another question. Is it possible to use a file/selection viewer as with SIO2IDE to make ATR selections on the SIO2SD? Would the same SIO2IDE software work for this purpose, perhaps with some modest changes? -Larry

I suspect it can't be done (at this time) -- but is it possible to add or remove an ATR image to/from the SD card directly from the Atari (without inserting the card into a PC)? Incidently, I've been using a little SD card to USB adapter to add/remove files from the card, and that works very well. -Larry

Has anyone with an NTSC computer successfully run this demo? The video freezes on my XE and XL after about 30 sec. The audio keeps going, though. -Larry

It all depends... XEGS: Roomy, but takes more space because of the detachable keyboard. (And I hate those round, pastel function keys! Keyboard: no big deal -- it's what you get used to. I actually prefer XE keyboards. Unless you are writing a novel... Upgrading: it will cost you $49 + shipping and quite a bit of soldering to upgrade it to 128K (if you are inclined) Video: the stock video is OK for composite, but no CV can compare with S-Video. PBI/ECI: Nope -- forget about hard drives, except MyIDE. But the MyIDE is a very usable HD, and it does keep getting better and better. 800XL: Still roomy for upgrades. Keyboard: many folks prefer it's keyboard to any XE. Upgrading: not too easy to upgrade. You can still buy the Wizztronics 256K boards from BEST, but quite a few folks have had difficulty getting the upgrade to work properly. (I have a Newell 256K that was already assembled, so all I did was to solder it in.) AtariMax may still have some XL upgrade boards. His is very nice (as are all the products he makes). Video: I haven't seen too many XL's, but those I have seen are terrible, and nearly all have no chroma output, so you have to add it. Not too difficult. PBI: Available, but there is currently nothing to add to it unless you can find a Black Box or an MIO. BTW, MIO's can only reliably use very hard to find MFM hard drives *with a bridge board controller*. So that pretty much takes you back to the MyIDE. You didn't mention getting a 130XE -- IMO, the best choice. If you would find one, you should ask the seller about the keyboard. But in fact, you should ask about the keyboard on any Atari computer. If you are satisfied with 128K, no further upgrades are really needed. My experience with XE's is very good. My original XE from about 1985 is still going strong. I've only had one XE that "went south" but its MB had been damaged with some "inappropriate" mods, so I can't really pin it on the XE. Having a 130XE also means that you could use the KMK-JZ IDE interface. It is flat-out the fastest HD interface available for the A8. Sometimes available from sellers in Poland. One caveat: some come without a cartridge interface. Since the HD interface plugs into the ECI, you can't use a cart with the interface. Mine came without the cart interface, but the solder connections are there on the board, so I ripped one out of a dead MB and soldered it in the interface. Works great. -Larry

Hi Urchlay- No, I only use a video card (All-in-Wonder) with the S-Video input. I've had lots of monitors, including 1802's, but this AIW setup is the best I've ever had. Maybe this 800XL was particularly ugly. I just have not looked at enough 800XL's to say whether this one was typical or not. BTW, I did not do the CV switch or disable. Next time I have it opened up, I'll add that. Here are a few screen shots of the finished SuperVideo XL, a stock XE, and an XE with the SuperVideo mods. Sorry, but I didn't have very good success with trying to save the screenshots as .jpg pics. They kept coming out very dark, so I zipped the (larger) .bmp files. -Larry

I ordered and received my SIO2SD from Pigula -- and it's really nice! Very professional! Mine was purchased completely assembled/tested. All I needed to do was prepare my SIO cable, attaching crimp-on connectors at one end. This can be seen in the photo: http://marcinprusisz.pl/sio2sd2/P3290069.jpg In addition, a small signal diode (included) must be soldered in the cable. I chose to install the diode at the SIO2SD end of the cable, just before the crimp-on connectors that are used. I did double-check to be sure I had the correct lines to connect to the SIO2SD! The docs are very clear as to the correct connections. From there, all I needed to do was FAT format an SD card (not included -- mine is a 512MB model), then create a folder called "Atari" and then copy a bunch of ATR images into that folder. Inserted the card, booted the Atari, and it sprang to life! The LCD display is excellent, and using the key-switches was easy with just a little practice. Having the LCD screen is extremely useful in selecting images and changing settings. The default high-speed SIO setting is a Pokey divisor of 6, or 68837. Using my Black Box high-speed drivers, I was able to successfully boot MyDos at a setting of 3 or 89488. At a setting of 2, or 99431, the system would not boot. I didn't try other drivers, although from past experience, I'm sure other high-speed drivers would perform similarly. I remember reading a magazine review (years ago) of the then-new US Doubler which said that the normal SIO beeps now sounded like a machine gun. This sounds like one of those multi-barreled machine guns! Am I happy with my purchase -- you bet! Best of all (as the guy on TV says) I didn't pay $200, nor $150, not even $100 including registered mail air delivery. The device does not include a case. I've decided to put it into a small plastic electronics project box. (Probably no Lego's... ) The only difficult part of inserting this in a case is that the push-buttons are about 3/4" below the level of where the case will be, so I will need to make some "extenders" to reach from above the case to the buttons. I have a pretty good idea how I will do this, and assuming I'm successful, I'll post a couple of pics when I' done. -Larry

Follow-up: I ripped the original SuperVideo 2.0 out of the XL and installed the correct values of single resistors. The display looked absolutely the same, so I must have done it correct originally. While I had the "piggy-back" resistors out, I did the mods as suggested by Bryan. As he indicated, it is less complex, but gave the same results on my XL as SV2.0. I would say that adding the 1K resistor from C55 to R58 (Step 4 in the Atari Classics SV2.1 section -- page 9) did improve the color saturation a bit. But on my 800XL, the step that made the most difference in the chroma saturation was Step 3 in the SV2.1 section. Replacing the 2K resistor with a 2.7K. I didn't have any 2.7K resistors, so I used a parallel pair (piggy-back) of 5.6K, 1/4-watt resistors. I checked these with a meter and got 2750 ohms -- close enough! It improved the saturation enough that I could cut the color gain on my capture card by about 25%. At this level, it looks like my XE's. It is now quite acceptable, and of course, immensely improved from the terrible stock video that this XL had. Hope this helps someone else. -Larry

In addition to "Mapping..." you might want to look at De Re Atari (also online at-- http://www.atariarchives.org/ ) and the Atari "Technical Reference Notes". As for the Basic compiler, I'm partial to ABC, since it provides the smallest code of the Atari Basic compilers. It should also be pointed out that frequently compiler code will not run as-is out of rom. You can still use it, but some parts of the code must be moved into ram in order to execute properly. Last, I'm no expert when it comes to the emulator, but think if I were doing your project, I'd do as much testing/debugging on the emulator as possible. Good luck! -Larry

I've always been partial to this genre. What are the best of this group for the A8? -Larry

The problem is that the video circuitry is messed up on a couple levels. The 75-ohm drivers were all wrong, but fixing them produces a stronger signal than was probably intended. These are the mods I recommend: http://www.atariage.com/forums/index.php?showtopic=41580 Hi Bryan- Thanks for the info and link. When I am re-doing the offending XL, I'll give this a try! -Larry

If you have a 1200XL, you likely have a type of "push rivet" that secures the top and bottoms of the RF shielding together. If you have an 800XL and probably a 600XL, you generally have small machine screws/nuts doing the same job. If you have an XE, you most always have little metal "tangs" from the bottom shield that you twist to clamp on the top shield. Of these, the XE system is the easiest/quickest to take apart and re-attach. In my experience, most XL's that have been apart several times have only the corner fasteners left in them. OK, that is quicker... Has anyone found a better small fastener to replace the screws or rivets?