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Actually when changing the option byte didn't work I changed it back. I played one session and did not notice any problems. Now I know what to look for in the other images that didn't work initially. Thanks again! - Steve Sheppard

Thanks Steve! I didn't see your message earlier. It might have save me some time! LOL! Then again, there's nothing wrong with trying to work things out for oneself. I gain a little more understanding. - Steve Sheppard

[Oops! Many typos. Fixed (hopefully] The option byte is $80 making this a diagnostic cartridge but changing it to $0 had no effect. I had already thought to search for references to $D301 but it did not occur to me to check $D300 (read on). The real thing is almost as easy for me. My BASIC ROM is really a 32K static RAM with battery backup. I found something interesting. If I use the Star Raiders image in Atari800Win Plus as the BASIC cartridge then the emulator claims that the CRC is unexpected, and then virtual Atari (not the emulator itself) crashes. This put me on the wrong track. For a while I was wondering if there is a CRC or checksum done on a BASIC cartridge by the OS. This didn't seem likely as many other game cartridge images work fine in the place of BASIC. Now to you suggestion, checking references to $D300, there was one store instruction. I changed it to NOPs but I have a question. Here is the relavent portion of the cart INIT code (sorry about the formatting). A162 LDA #$00 ; 2cyc ; A9 00 A164 TAX ; 2cyc ; AA A165 STA $D000,X ;HPOSP0 ; 5cyc ; 9D 00 D0 A168 STA $D400,X ;DMACTL ; 5cyc ; 9D 00 D4 A16B CPX #$0F ; 2cyc ; E0 0F A16D BCS $A172 ; 2cyc ; B0 03 A16F STA $D200,X ;AUDF1 ; 5cyc ; 9D 00 D2 A172 STA $D300,X ;PORTA ; 5cyc ; 9D 00 D3 A175 STA $0067,X ;MLTTMP+1 ; 5cyc ; 9D 67 00 A178 INX ; 2cyc ; E8 A179 BNE $A165 ; 2cyc ; D0 EA Here is the patched code. (This is disassembly from the Atari800Win Plus monitor, BTW). A162 LDA #$00 ; 2cyc ; A9 00 A164 TAX ; 2cyc ; AA A165 STA $D000,X ;HPOSP0 ; 5cyc ; 9D 00 D0 A168 STA $D400,X ;DMACTL ; 5cyc ; 9D 00 D4 A16B CPX #$0F ; 2cyc ; E0 0F A16D BCS $A172 ; 2cyc ; B0 03 A16F STA $D200,X ;AUDF1 ; 5cyc ; 9D 00 D2 A172 NOP ; 2cyc ; 1A A173 NOP ; 2cyc ; 1A A174 NOP ; 2cyc ; 1A A175 STA $0067,X ;MLTTMP+1 ; 5cyc ; 9D 67 00 A178 INX ; 2cyc ; E8 A179 BNE $A165 ; 2cyc ; D0 EA The orginal code would appear to loop 256 times as X register counts up from 0 and back to 0, setting many locations to an initial value of 0 (the contents of the accumulator). By simply using NOPs in place of STA $D300, X I'm preventing the initialization code from zeroing out locations $D300 thru $D3FF. The patched code seems to work (in the emulator and my real 800XL) and I know there are hardware adresses not RAM but are there any bad consequences to not zeroing them? Thanks for your help, Rybags! I might have figured it all out for myself. Then again I might not have. LOL! - Steve Sheppard

I'm interested in this too. The images of Star Raiders I have work in a cartridge but not as a replacement for the the 8K BASIC ROM (in my case a 800XL). Many 8K images work but some don't, many activision cartridges for instance. I've always been curious why. - Steve Sheppard I would suspect that the carts that don't work are the ones that get control immediately (ie - diagnostic mode carts). Lots of games use that mode, especially since some early cartridge games would even allow a cassette or disk to boot (which was an easy copy method). Typically, a diagnostic mode cart will perform the system coldstart/warmstart itself, which involves writing zeros to all the hardware registers. As such, PORTB could easily end up being set incorrectly. Well, that's easy enough to check but what might I modify to make it work? Would I need to add instructions to set up PortB? Turn of the diagnostic cart mode? Change the init sequence? This is killing me. I want my 800XL to boot to Star Raiders! - Steve Sheppard

The ATR8000 is a multiple I/O interface for the A8. It connects to the SIO port. Has 1 serial port, 1 printer interface w/ 16K or 64K buffer (depending on model), and can control 4 industry standard floppy drives which are connected externally to the unit. Internally ATR8000 is a full fledged 4Mhz Z80 computer. The 64K model can run the CP/M operating system. In this mode the the Atari normally acts as the console but a real RS-232 terminal can also be used. - Steve Sheppard

I just got there, Iguess Imissed the fun see ya on tuesday for the chat. Sorry Dan. I was there but I didn't look up when you arrived. Tuesday it is! thats ok steve, ig uess not many people showed up for the chat today anyways. No not many, only four people today. Quick Recap: - mdgames was there when I arrived. I was 20 minutes late and really sluggish. After 3 stops for coffee I finally started chatting for real - mdgames is working on a new game dual (that's two games, not a fighting game) for Jaguar. He's trying to put the AI routines on the Jaguar's RISC processors. The details were beginning to go over my head! - I embarassed myself by thinking mdgames is the friend of Beetle. I still can't remember that friend's nickname. - Stephen showed up. He was ripping out his kitchen floor and said that is why he was late. That's no excuse for missing chat in my opinion. LOL! His hand is almost healed after last week's mishap. - Mr. Atari popped in then had to respond to a customer. We talked about MyIDE, as usual. - - Mdgames asked Mr. Atari to test thenew games. - I took a break for lunch. When I returned Mr. Atari's had been talking about his movies. I missed the details. He had to leave again. - That's about it. Chat broke up around 2:00 EST.

I just got there, Iguess Imissed the fun see ya on tuesday for the chat. Sorry Dan. I was there but I didn't look up when you arrived. Tuesday it is!

It's Sunday, September 24, 11:45 EST. Am I early or late? Just MDGames and me in the chatroom. Come join us.

I'm interested in this too. The images of Star Raiders I have work in a cartridge but not as a replacement for the the 8K BASIC ROM (in my case a 800XL). Many 8K images work but some don't, many activision cartridges for instance. I've always been curious why. - Steve Sheppard

You can get an SIO2PC interface working on some pretty old PCs. The original SIO2PC, back when the name meant the software not the interface cable, ran on a 80286, at least I think it did. I use AtariSIO (Atari disk emulator for Linux written by Hias Reichl). It has pretty minimal system requirements, though I don't know not what the lower limit is. The slowest machine I use is a Toshiba Libretto 50CT, a Pentium 75 system. I use the bootdisk version of AtariSIO but you don't actually need a bootdisk (floppy by the way) to use it. The mini Linux it runs on will launch from DOS. Just for fun I made a couple of bootCDs (eltorito format), one each with plenty of binary files and/or ATRs. Had another CD that loaded random games but I lost track of it. It was just a novelty. The boot CD, in general, is cool because it doesn't need a hard disk. Just boot from the CD and you're serving up Atari files. - Steve Sheppard

Sorry, I guess I wasn't clear, myself. Two bytes total. That's one CARD, or one INT, or two BYTE parameters. The issue has to do with where Action passes the parameters. If they were passed on the 6502 stack then all would be well but they are not. I've got to re-read the tutorial again and track down the other article that describes writing code that doesn't need a run-time library. BTW, three pages earlier in the manual (page 63 in version 3.6) I found this, "TECHNICAL NOTE: the Action! Compiler does comparisons by subtracting the two values in question and comparing the difference to 0. This method works correctly with one exception -- if you are comparing a large positive INT value with a large negative INT value, the outcome could be wrong (since INTs use the highest bit as the sign bit)!!!! - Steve Sheppard

Hi Gury, I have seen this information somewhere else. I'm pretty sure it is a description of how to write Action! code that does not need the cartridge nor a runtime library, which is why it mentions avoiding library calls and multiplication. If you look back at Larry Seflaten's tutorial it states to limit parameters to two BYTES, not two PARAMETERS. To change the subject (a little), I was recently informed, by a good friend, that there is a bug in the Action multiplication routine. It involves CARD types. If the result, final or intermediate, of a multiplication operation should result in a number greater than 32767, then that value will be erroneous. (See technical note page 63 of version 3.6 Action Ref. Manual), This error applies to the multiply function built into the Action cartridge and may or may not have been corrected in one or more of the runtime libraries. - Steve Sheppard

Wow! I never realized there was a separate beige line. A beige 800 probably would have held up better than my khaki (or was it originally tan?) 800. It's sort of a puke green now! Yuck! But it still works! - Steve Sheppard

Star Raiders has been mentioned but it needs to be on the top of list, IMO. Something about that game. During the 90's, I probably kept the 800 just for that game. Other must-haves for me are, Joust, Miner 2049'er, Boulder Dash, the new (2005) Flowers Mania (very addictive), Missile Command Plus (a recent hack), and almost every other game already mentioned. I'm not sure about being sleepers but games I associate with the A8 only (whether it's really true or not), include Way Out, Preppie, Behind Jaggi Lines (was this ever released?), Caverns of Mars (need a precise joystick), Ball Blazer (and ureleased Ball Blaster), Arkanoid II (OK I really remember the arcade version the best but the A8 one is very good). They are not on the top of my play list but are must-haves all the same. Comments: Someone mentioned Ducks Ahoy. I crack up whenever I just hear the name! LOL!. Tapper is another one! - Steve Sheppard

A standard C-60 tape is 30 minutes per side. The cassette runs at 600 baud. Call this 60 bytes/sec, so 30 * 60 * 60 = 108,000 bytes per side That's a very rough estimate. With leading spaces and with inter-record gaps (long or short) the actual number is less. How much less? I don't know. - Steve Sheppard

Several years ago I purchased Connectix's Virtual Game Station, the only authorized PSX emulator (AFAIK). It worked well but doesn't look as good as a PSOne. (Were there quality differences between real PSX and PSOne?) There is only a limited choice of game controller types (keyboard, joystick, and basic digital gamepad, (IIRC) that work with VGS and there is no force feedback support. I don't know if you can find Virtual Game Station any longer. Connectix stopped selling it after about two years of production. Rumor was Sony bought the line to squish it out of existence. Possibly because VGS can run "backup" copies of CD's and also mounted images. - Steve Sheppard

Ooh! Someone with a real disk! If you can crack the disk great, I applaud you for the effort! However, please consider preserving your disk by making a VAPI image (see link for information). Time is running out and your disk won't last forever. Here's the VAPI link. http://vapi.fxatari.com/ Hopefully this contact information is still applicable. vapi@fxatari.com - Phsstpok

I have not done a lot of this but I managed to restore one stubborn tape. Here's how I did it. -MagoTrans seemed to make a better set of .CAS files than WAV2CAS. -CAS2CAS (the only recovery program that I have seen to date) was able to recover all bad blocks for my particular tape, Analog Software's, "Shooting Gallery". Not sure how CAS2CAS works but it takes 3 seperate input files (2 .CAS files and 1 .HEX file OR 3 .HEX files, don't ask me why) then tests for good blocks making the best choice(s) for the output file. -I also routinely make two separate .WAV files from each tape program. I use Left channnel for one recording and Right channel for the other recording. You don't always get the same bad blocks on each channel. - Steve Sheppard

Did you try making a custom keyboard template? If you don't need the numeric keypad you might remap one of those keys to be an Atari ESC. For example you remap [Keypad *] = [Atari ESC]. Now if you press Ctrl + Shift + [Keypad *] you get the Atari action for Ctrl + Shift + ESC but don't trigger the Windows action. Alternatively you can map a single Keypad key to be the whole Atari Ctrl + Shift + ESC combination. Unfortunately, I don't see a way to re-map a PC function key to do this instead. This would be ideal as I like having full use of the keypad. - Steve Sheppard

I missed that product. Where can I find more information on AtariMax 31in1? I cannot find it on the AtariMax Website. It would be more a solution for future upgrades, or to merge the existing custom OSes, instead of just hosting the OSes unchanged. Carsten How about using a variation on Bob Woolley's SmartOS? In part one of Bob's SmartOS articles he described using static RAM with battery backup. In the original article the SRAM was used as a replacement for not just the OS ROM but also the internal BASIC cartridge and for providing non-volatile memory at $D600-$D6FF and also $D700-$D7FF. What if we combined your extensible OS with Bob's SRAM concept? I think addresses in the range $D600-$D6FF have been used for other hardware projects but $D700-$D7FF has gone mostly unused. We use some of these addresses for vectors and temporary variables and some adressess for banking control. I propose that we design the extensions to function as 2K banks at the address range used by the self-test ROM code. Under normal usage the self-test code is not needed once Atari A8 has booted. We can even keep that original code, in the home bank. The banking controls should be designed so that each and every bank can be protected yet allow the possibility for some banks to remain in "RAM" mode, possibly to be use for temporary storage. If what I propose is possible I think it would have minimal impact on existing hardware/software. I have to admit (LOL) that I don't know how to implement this hardware scheme. I'm also not sure what would be the best locations to hold the code that would control the banking feature. Does anyone think this idea is even possible? - Steve Sheppard

By 'bundled' do you mean included? I remember the Atari 400 being like $200, and had to scrape up another $50-$60 for BASIC, and another $100 for the 410 cassette recorder. Course it wasn't too long after than the XL's were coming out and they slashed prices a lot. I know at the time I remember Apples and TRS80 model 3's that had basic built in at school, but not sure if that was an add on option or not for those machines. I can't speak for 400's but early on the 800's were bundled with BASIC and the BASIC Reference Manual, The 800 Operators manual, and the 410 Cassette (the one with handle). The retail price for the package was $999 (but that was probably the 48K model). - Steve Sheppard

LOL! Back in late 1978 my buddy from college said, "You gotta see this new amazing computer. It's called Atari!". So I went to Computer City (I think that was the store) and all they had were brochures and cardboard mockups or poster boards but I was already hooked! For weeks or months my friend kept telling me, "You gotta buy the 800!". (He had a TRS-80 Model 1 at the time). In 1979 I still couldn't buy an 800 locally. 400's were a plenty but no one had the 800 in stock! I finally found a mail order vendor selling 800's bundled with an extra 8K for a total of 24K. This was a major find because memory upgrades for the 800 were rarer than the 800's themselves! 48K 800's were way too expensive, an extra $360, IIRC. The price for my bundle was $749 (USD btw) and I think free shipping. This was more than a semester's tuition at the time, but I bought it! ( Passed up owning a car for one more year). Sometime in 1980, I think, my friend bought a Color Computer! He decided that the 800 that I should have wasn't worth his time or interest! %$#^%$#&$!!!! I still have and use the 800 but my buddy's CoCo has long since bit the dust! I have to admit the 6809 WAS a nice CPU and the CoCo family of computers ended up with a nice OS, IIRC. - Steve Sheppard

I think you're right about all the other features, but the Commodore PET included BASIC in all models, beginning with the 1977 release. Hey you are right! I forgot about Commodore Pet. Nice machine! - Steve Sheppard

LOL! all my text just vanished leaving only a quote of the original post. I'm too tired to type it all again. Here's a condensed version. (Luckily for all you readers). - Who said clone hardware didn't appear until the mid 90's? I still have my 1987 Media Vision Thunderbird [EDIT: that's Thunderboard not Thunderbird] soundcard. It is a clone of the original SoundBlaster (circa 1984). My Paradise VGA+ was a clone for you guessed what. Also purchased in 1987. The VGA+ was intalled in a 286 system with AMD clone 286 processor. The system originally contained a clone of a Hercules graphics card which in itself cloned the IBM MDA monochrome text card but added monochrome graphics to the mix. Clones of Hercules cards usually included a printer port. I guess you could call it a clone printer port. I'm looking at my IBM PC XT Technical Reference manual (Revised edition 1983, original 1981). Enclosed are XT schematics and the complete BIOS source code. Doesn't look like closed architecture to me. ======================================================== Regarding the Atari 800 being revolutionary. I think these were all new features in 1979 - built-in gaming hardware including player/missiles, sound with digital processing, game ports, cartridge port (Pretty sure other computers needed additional hardware to enable joysticks). - built-in light pen support (OK this was almost useless). - Console keys (new but no big deal) - the ability to connect to a TV and have sound right out of the box. - In 1979 I believe Atari was only the 2nd manufacture to have bundled BASIC, Radio Shack/Tandy being the first. - first computer with palletized color (I think). Just my opinion, but all these features did make the 800 revolutionary in 1979 and probably so for the next three years.

Woops! Double post! Sorry. Could you be speaking about this game DOS, Micro SpartDOS by BEWESOFT? - Steve Sheppard