Propane13

Street Racer?

Hey Mitch-- Actually, I think it went the other way. No one ever contacted me for sales of "Possible Mission". And, I was concerned over copyright concerns back in the day. I had wanted to make this a saleable product (since it took a few weeks of hacking code to get it to work-- I'd say it was a significant effort). But, now I really don't care-- I'd rather have it in the hands of those who want to play it. Since I'm not really too involved in the community anymore, I'd consider publically releasing my hack for free. Is it still of any value? Regards, -John

Actually, this is what happens if you take a raw 7800 bin, and convert the whole thing to graphics. The "snowy regions" are what code looks like when turned to gfx. Regards, -John

For more fun, do the same thing to Joust and Asteroids. I did this a coupla years ago-- there are some interesting things to be found (like programmer names embedded in graphics). Never figured out how to unlock them in the games themselves tho. Regards, -John

Hi everyone, Long time no post. Anyway, I decided that If I don't post this now, I never will. My 7800 programmer's hat has been hung up for well over a year. I had some very good projects that I was working on (which some of you knew about) that I should probably share. One of them was the partial disassembly of the diagnostic cart. The weird screens and everything-- no longer a mystery. Enjoy. Found here: http://www.cs.wisc.edu/~harvey/7800/diag.html Thanks, -John

I wouldn't have ever believed it if I hadn't seen that video... I am shocked. -John

Hi, I believe this had to do with bribing the sheikh to get to the Black Market instead of using the regular way. Regards, -John

Hello, I had originally done the "rainbow cart". It was called "2600-Post-It-Note" (1 message w/ up to 990 chars), or "Alphanumeric Madness" (2 messages, 500 chars each, switch on Fire button") depending on your choice. You could choose the scroll speed (0=slow, 255= real fast), and the color of the text (1-255 in the Atari pallete). I can still make a customizable bin for you if you wish, but I'd need to dig through some old tools to be able to do it. Might take me a few days. Send me a Private Message with the details if you're interested. Regards, -John

http://digitpress.com/archives/arc00049.htm

sorry; double post

If I remember right, I think there are 2 chips in the cart-- one is the 8K ROM for the game logic, and the other is the DPC-- it includes 2K of ROM (game graphic data) plus all the bells and whistles that the DPC includes (music multiplexer, oscillators, etc). So, someone would have to re-invent the DPC if they wanted to hack Pitfall 2 graphics. But other game logic would be up for grabs. I don't remember too well tho; it's been awhile since I cracked open a P2 cart-- so, anyone, is it one chip or 2? -John K. Harvey

Hi there, P2plus was probably scrapped for many reasons: 1) The native Pitfall 2 code is complicated-- just changing map items does not remove collision detection. Actual game code needs to be changed to do this, which is nontrivial 2) There is no saleable market for it. No one could reproduce these carts because you would need to create boards that support a DPC, and you'd need to have DPC's. You can cannibalize Pitfall 2 carts for this, or try to find a place that sells them (good luck). 3) Even if you did manage to get a bunch of DPC's and etched boards that supported them, you'd never be able to change any of the graphic colors or sprites. They're all encoded in the DPC. Essentially, you'd need to be a hardware wizard and create your own DPC clone out of a PIC or some sort of hardware. Lots of effort here. So, this means you would only be able to play it on an emulator after a lot of investment of work. In my opinion, Pitfall 2 is the best 2600 game ever created. Why would anyone want to try to recreate or re-map perfection? If you wanted to make your own carts, you may end up cannibalizing Pitfall 2 carts, which is a terrible thing to do to such a great game. Seems like a wasted effort to me. I think the best way to appreciate the game isn't to hack it, but to play it. Just my 2cents. Thanks, -John K. Harvey

Nuts... There go my dreams of releasing Pressure Gauge Special Ultra Mega 2003 Edition with the "Mega Just-a-Button" controller. -John K. Harvey

Awesome!!! Finally, a portable version of Pitfall 2! This will make my Christmas list indeed. Is the list of games set in stone? I assume the cutoff date for homebrews has long-since passed, since you're in beta-testing. Thanks, -John K. Harvey

New Question for DASM users: Say that in 2600-land, you've got a six digit score routine that does fetches from 6 different locations: F500 F580 F600 F680 F700 F780 The code does a LDA F500,X stored to GRP0 and then LDA F580,X stored as GRP1, etc... So, all you need to do is increment X to point to 6 new points of data. From a disassembly perspective, this sucks a bit. You'll have 6 vertical blocks of graphics data that are all supposed to be sandwiched together, and you can't grasp the full effect unless the code is running, or spliced together. So, in DASM, is there any way to do the following (perhaps with a macro): macro Unknown ... endm Unknown (F500_data, F580_data, F600_data, F680_data, F700_data, F780_data) Unknown (F501_data, F581_data, F601_data, F681_data, F701_data, F781_data) I have a feeling if I create some data re-arrangement macros, they will fail due to origin-reverse-indexed errors. Any ideas? Thanks, -John K. Harvey

ldx #$20 Lfb8e: ldy #$00 Lfb90: iny bne Lfb90 dex bne Lfb8e bit INPT0 bpl Lfba0 Hmmm... this doesn't seem to be all encompassing. Last I remember, the worst-case that I had for paddle detection when the paddle was at maximum resistance was 400 scanlines. So, if your paddle is at full resistance, it may not get detected. See this stella list link for confirmation: http://www.biglist.com/lists/stella/archiv...7/msg00146.html So, since there are no WSYNCs in this loop, how many WSYNCs does it equate to (just computationally, by cycles)? If your paddle is at maximum resistance, will it not get detected? Perhaps some more experiments are in order. Thanks, -John K. Harvey

Hello, I had a quick question for any of you hardware people out there. I don't understand too well the hardware info for the paddles, since I'm mostly a software guy. I want to make some hardware that I could put into joystick port 1 in order to simply make a game like Astroblast detect that I have the paddle installed. I believe these games just check to see if INPT0 or INPT1 gets set (or cleared; I don't remember) after a certain amount of time. If the transition occurs, then the paddle is installed. So, I was wondering what the simplest circuit would be that does the following: 1) sets or clears inpt0 (whichever state means that the paddle is there) 2) sets or clears inpt1 (whichever state means that the paddle is there) Would I just wire pin 5 to ground (pin 8 ) fot the first case and pin 9 to GND for the second case? Or perhaps tie them to VCC? Or, do I need resistor or something so that nothing explodes? Thanks, -John K. Harvey

Hello, I own: Space Treat Marble Craze Pressure Gauge Edtris SoundX Mental Kombat I've played a lot of the others as well; indeed most of them are fun too. All are fun, but my recommendation goes out to Marble Craze. -John K. Harvey

No, one eh? Well, I had made a demo once... Check out the "[stella] Teleterm 2600" thread under: http://www.biglist.com/lists/stella/archiv...08/threads.html It wasn't so much a game as it is a text transmission mechanism; send and receive true rs232 serial (no UARTS) with just a few wires. It was an awesome project Thanks, -John

Hi-res mode wasn't used because it sucks. The main issue with hi-res sprites is the lack of palletes. You're limited to 2 in this mode. So, that's a total of 7 colors possible (background, plus 2x3-color). However, in this mode when objects overlap, there is no transparency (so any overlapping objects will display the background color to show around the sprites, causing crappy-looking results). If you turn transparency on to circumvent this issue, you lose your resolution (back to 160), and in addition, you lose some colors in your palette (now limited to 5 colors, IIRC). So, these sprites are pretty useless for any functional game-play sort of thing. So, that limits you to picture drawing. But, who wan't to draw a high-res picture with only 7 colors? Thanks, -John

I remember taking Tower Toppler back to Toys R Us as a kid because I thought it was defective. When the exchange copy exhibited the same problem, I then read the manual -John

Just curious as to if anyone's ever been that bored. Does it loop after that point, or is there an end screen? Thanks, -John K. Harvey

Hello, I just checked, and I found 'em at Best. Thanks for your help, CPUWIZ; you got me thinking about it, and I managed to track them down. -John

Thanks, CPUWIZ, I think that sounds like it could be it. There is no mention of this at the Diagnostic cart page on atariage. Does someone have a picture they could post, or know of one on the 'net? Also, are these items rare, or can they still be obtained for a reasonable price (say, through Best Electonics or somewhere)? If they can't be obtained easily, does anyone know how to replicate the hardware? I'd be interested in creating or buying one of my own, just for kicks, and for some experimentation. Thanks, -John K. Harvey

Hello all, I remember somewhere in my travels seeing someone who had an interesting device that plugged into a 2600 joystick port; it had a red and a green LED on each side (I think). I believe that you had to run some cartridge software with this thing in the joystick port, and afterward, it would light up "green" or "red" depending on success/failure. Unfortunately, it's been a long time since I saw this item, so I don't remememeber much about it. 1) Does anyone know what I'm talking about? Does anyone have this item? What is known about it? 2) If you don't have the device specified in my crappy paragraph above, but know of something else that was made for automatic joystick diagnostic purposes (not of the homebrew era), can you describe it here? Thanks, -John K. Harvey