DanBoris

Very nice work! The compatibility is excellent, you can run games in your first release that my emulator still can't run after all these years. Decathlon and MrDo's Castle have always been problems for me, but they run great on your emulator. You also managed to find the tricky little controller issue that would cause Star Trek not to start. A few issues I have spotted: Most of the graphics in Kaboom are missing, I am guessing that you haven't implemetned the GRAFP0..3 registers which are used to write directly the the PM hardware bypassing the DMA Alternate version of some carts do not work. This is probably a cart loading problem. 5200 carts where not all dumped in uniform ways, so there are multiple version of the same rom image floating around for some cartirdges. For example there is a 4K and 16K version of Kaboom, the 16K works, but the 4K doesn't. Dan

I was also at that auction on Saturday, sold the Monaco GP machine I had refurbished. They had some interesting items I was temped to bid on (two really clean Asteroids machines, Star Wars pinball, Missile Command cabaret), but didn't go for anything. The other auction company that used to come to that same location didn't charge a bidding fee, but thier buyers premium was higher so it was a tradeoff. I am guessing that UsAmusements charges simply make a little extra cash. They also use it as a small perk for sellers, since they don't have to pay for a bid card. Dan

Yes, the empty 14 pin slot is for a 7404 inverter chip. You should be able to put an inverter in there and cut jumper W3 to make the cartridge work with an EPROM. You can see how this works from the schematic here: http://www.atarihq.com/danb/7800cart/C026461.shtml Note that you will not be able to use the 7402 NOR Gate without some extra modifications. Dan

Actually most of the "ROM package" changes are important to MAME's preservation goal. Whenever it is discovered that there is something incorrect about a ROM set it is updated so that MAME always supports the "best known" set which is really the one you want to preserve. Dan

I'll be there on Saturday. Dan

This still leaves some holes in the memory map. If you take a look at the address decoding on the schematics you get a memory map that looks like this: |15 14 13 12 | 11 10 9 8 | 7 6 5 4 | 3 2 1 0 | |--------------------------------------------| RAM |0 0 A A | A A A A | A A A A | A A A A | 0000 - 3FFF CART407F|0 1 A A | A A A A | A A A A | A A A A | 4000 - 7FFF CART80BF|1 0 A A | A A A A | A A A A | A A A A | 8000 - BFFF GTIA |1 1 0 0 | X X X X | X X X A | A A A A | C000 - CFFF POKEY |1 1 1 0 | 1 X X X | X X X X | A A A A | E800 - EFFF BIOS ROM|1 1 1 1 | A A A A | A A A A | A A A A | F000 - FFFF In each line, the 0/1 are fixed values, A means this address line is connected to the chip, X means doesn't care. This gives the address ranges listed on the right side. This still leaves one hole, D000-E7FF. All 16 address lines go to the ANTIC chip and it does it's own address decoding. We know that it appears at the very least between D400-D4FF and Atari's Antic documentation confirms this, but it's still possible it mirrors into other areas. So this leaves D000-D3FF and D500-E7FF undecoded. Dan

I know about these and I'm pretty sure that whole pages are used for mirrored registers. But what's in $C100 - $D3FF, $D500-$E7FF and $E900-$F7FF ? 960057[/snapback] The mirroring actually occurs through more then just one page. For example POKEY is enabled when A15=1, A14=1,A13=1,A12=0 and A11=1, the rest of the address bits don't matter. So $E800 will access the same register as $E900, $EA00, etc. Dan

Accoring to Curt, the KERI is an ANTIC/GTIA/POKEY combination chip. http://www.atariage.com/forums/index.php?s...ndpost&p=909032 Dan

Here is a theory I had on this... If you have looked at the 7800 PCB it's pretty crowded, so adding a pokey to the design probably would have increased the size of the PCB, the size of the system, and the overall cost of the system. A lot of the 7800 carts had one of three "added features", extra RAM, extra ROM, or a POKEY, so the Pokey cart would not have been much more expensive then the other carts to make. Even if you had to tack on a few dollars to the price of the cartridge, this may have actually been more palatable to the consumer then increasing the price of the console by say $10.00. Dan

My 5200 emulator VSS is command line and works fine under XP with the help of vdmsound (http://sourceforge.net/projects/vdmsound/). You can get it here: http://www.atarihq.com/danb/a5200.shtml Dan

There was a book put out called The Atari BASIC Source Book that has the full source code the the BASIC cartridge. You can find the book online here: http://users.telenet.be/kim1-6502/6502/absb.html If you browse through the code you can see how each basic instruction is executed in assembly. For example here's the code for the POKE statement: XPOKE - Execute POKE B24C XPOKE B24C 20E0AB JSR GETINT ; GET INTEGER ADDR B24F A5D4 LDA FR0 ; SAVE POKE ADDR B251 8595 STA POKADR ; B253 A5D5 LDA FR0+1 ; B255 8596 STA POKADR+1 ; ; B257 20E9AB JSR GET1INT ; GET 1 BYTE INTEGER TO POKE ; B25A A5D4 LDA FR0 ; GET INTEGER TO POKE B25C A000 LDY #0 ; GET INDEX B25E 9195 STA [POKADR],Y ;GET INDEX B260 60 RTS Dan

Have you tried cleaning the contacts? 99% of "bad" cartridges can be fixed just with a good cleaning, and this can be done without taking the cartridge apart. Dan

I recently visited a great arcade called "Challenger Arcade" in the Berkshire Mall in Wyomissing, PA and felt like I was stepping back into the 80's. Among the classic machines they had: Pac-man Ms-Pacman Galaga Crystal Castles Paperboy Tempest Star Wars Dragon's Lair Dragon's Lair II Super Don Quix-ote (first time I ever saw one of these) Space Duel Track and Field Road Runner Baby Pac-man All thier machines where is excellent working condition, obviously well taken care of. They also have some newer machines, a shuffle ally, skee ball machine, and a couple of pinballs ranging from old electro-mechanical ones up to modern machines. Dan

Yes, I tried this. Once you know the pattern, it's really easy to hit the score. Dan

I remeber back when I was writing my 2600 emulator that the startfield in Cosmic Ark gave me a lot of trouble. It uses a pretty obscure technique that the FB2's TIA probably doesn't handle properly. Dan

To be more precise, it probably marks that as pin #24. You can see the 1 next to the pin right across from it marking it as pin #1. "BIT - 702 - 1" is probably the part number of the PC board. Dan

New chapter is up now! I takes me a while to put each chapter together since I am posting things as I go along. Drawing the schematics based on the really poor quality scans I have is the hardest part and takes a bit of time. Dan

Wish I knew! I already checked the Amiga idea, the Amiga chip has more pins. The part number and date on the list for Paula are pretty low, which makes it likely that it's for use in the 2600 or 8-bit computer products. Dan

I dug out some old Atari chips that someone gave me a while back and one of them appears to be the CO11903 PAULA chip, see the attached picture. I got these so long ago, that I have forgotten what they where supposed to be. Dan

Here's the Quad Pokey from the Major Havoc schemaitcs. I-Robot uses one also, but the part number is different then on the list. It's still possible it's the same chip, might just have been given a different part number in the arcade divsion. From what I have read the Quad Pokey's are hard to come buy, to the point where someone started selling Quad Pokey eliminators which was a PCB that went in place of the Quad Pokey and had sockets for 4 normal Pokeys. Dan

The Quad Pokey was used in Star Wars, Return of the Jedi, I-Robot, Major Havoc, and maybe some others. I have seen the ANTIC-E referenced in a few of the documents on Kurt's site, but nothing that actually describes what it is. Dan

I found this list so interesting I put together a web page with a cleaned up version of the list along with descriptions of the known chip. If anyone has anything else to contribute please let me know and I will add it to the list. http://www.atarihq.com/danb/AtariChips.shtml Dan

Curt, This is really cool stuff! The ones that jump out at me are: STELLETTE - Name would lead you to believe this is a variation of the TIA chip from the 2600. fast 6507, fast 6532 - Where they planning a version of the 2600 with a faster clock speed? RAINBOW GOLD and RAINBOW SILVER - These names just sound cool! I would assume these were some form of graphics chip. Dan

I thought this was interesting. It appears to be counting the number of scanlines in a video frame. FFCB: 24 28 bit $28 FFCD: 30 FC bmi $FFCB FFCF: A9 9E lda #$9E FFD1: A0 00 ldy #$00 FFD3: A2 00 ldx #$00 FFD5: 24 28 bit $28;Wait for VBLANK FFD7: 30 07 bmi $FFE0; FFD9: 85 24 sta $24;WSYNC FFDB: 85 24 sta $24;WSYNC FFDD: CA dex FFDE: D0 F5 bne $FFD5 FFE0: E0 78 cpx #$78;Branch if > 120 FFE2: B0 04 bcs $FFE8; FFE4: A9 98 lda #$98 FFE6: A0 2B ldy #$2B FFE8: 85 30 sta $30 FFEA: 8C 01 20 sty $2001

Where is this from? Dan