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560/561 points to the display list. You need to change the display list itself to point to your own screen Ram. In most cases display list + 4 will be what you need to change.

I am confused here when I read my array and poke that directly to screenmemory I dont have to change 560/561 var sc : word absolute 88; for i:=0 to 959 do begin poke(sc+i,screendata[i]); end; So this copies data from array to the current screenmemory. How is it impossible to point screenram to the start of an array ?

Damn, I was hoping for a spiritual sequel to one of his other games, maybe titled "Generic Non-Spielberg Space Alien"

Didn't Scotty invent transparent aluminum back in 1986? It seems to me that would be the best solution in recreating the 800's metal shielding to be able to see straight through a clear case. 😁

Location 88,89 is just the pointer to screen Ram that the OS refers to when doing character writes or pixel plots. There's also the actual screen addresses fetched by Antic which are in the Display List and you'd need to change those also. Typical Display List (560,561) will contain: 112 (3 times) 8 blank scanlines 66 LMS Antic Mode 2 (Gr. 0 ) low byte screen Ram high byte screen Ram 2 (23 times) 65 (Jump and wait for VBlank) low byte display list address high byte display list address You'd also need to ensure the screen memory doesn't cross a 4K boundary - without another LMS Antic will just wrap around and read from the current 4K block start.

I've designed a multibank card for my COCO2 and I tinker a bit with drivewire. I've flashed "HDB-DOS 1.1D DW3" in one bank of my card and got it working, but I also have some instabilities. Sometimes the computer freezes when loading a game and I need to go through a power cycle to bring it back and then the same game can load wihtout an issue. I have a jumper to enable /disable autostart, I will give it a try. However I'd like to know where I can find the latest HDBDOS version for Drivewire. I've been following the links from here and only found v1.1d : https://www.cocopedia.com/wiki/index.php/Getting_Started_with_DriveWire

How long did it take to make the Colecovision DK? Because if it took a lot longer than 90 days, and could afford a ROM larger thank 4 or 5 KB, then it sounds to me a lot like “never mind the budget — make sure ours looks and plays better than the others, whatever it takes!” sort of situation. In that view, the programmers for the other consoles may not have been asked specifically to make crap games, but that sounds like a distinction without difference. dZ.

Does that mean Yars' Academy is planned for the VCS 800?

I believe there is a bipolar 1uf cap in the reset circuit. If it's a reset issue, replacing that may fix it.

It looks like it may have come apart some.

I won't argue with the fact that Wolfenstein 3D looks awesome on the Jaguar. I had two games on my Jaguar, Wolfenstein 3D which I liked and Cybermorph which was garbage. My problem with the Jaguar is not as such the specs of the system but the lack of third party support for the console. Also from the few games that actually made it to the system almost none of them took advantage of the claimed 64 bit power. Games on the Playstation and Saturn, both 32 bit albeit released after the Jaguar look better. Heck, most Jaguar games don't look much better than similar games on the 16 bit SNES. So no matter what the hardware can do, without decent 3rd party support its bound to fail. Same with the Atari Lynx, a portable which holds very dear to me because it was my first handheld. It was technically superior to the pea green Gameboy or even the Game Gear and had a few great games which I already mentioned, it also has a lot of crappy games. I don't care for the recycled old Atari arcade ports they made for it just because it lacked support from publishers. Honestly, I am not an Atari basher. So much so that my first ever computer was a 65XE and I have fond memories of playing games like Henry's House, Pac Man, Mario Bros, Pitfall etc.

It's not necessarily a bad thing to have third parties develop your games, but you get the quality that you are willing to pay for. A lot of XEGS games were disk games ported to cart.. cheap! Even today a lot of exclusives are developed by third parties, and sometimes those studios are bought by the platform holder if they do good work. Atari today has been doing that, but back then I don't recall Atari buying any game studio back then. Epyx would have been a good purchase and fit for them, certainly better than the money Atari wasted buying Federated or Abaq (the Transputer workstation)

Hello, I have a few screens embedded in my code. Those are array's of bytes. I would like to switch between the array's on graphics 0 and not copy the data to screenram but point screenram to the begin of the array. array1 ... array2 .... p:^înteger; InitGraph(0); p:=@array1; I did try dpoke(88,array1), dpoke(88,pointer(array1)) and dpoke(88,^array1) and dpoke(88,p) maybe its just syntax but whats the way to do this ?

I'm going to wrap up my repairs with one final saga. I was always seeing diagonal noise in the RF output no matter what I tried to cut out interference (cables, power, room location, thoughts and prayer, ...) . This lead me to rigging up a simple composite mode (the few resistors + cap + 2n3904). Composite has significantly less random noise, but the diagonal banding persisted and because of the cleaner picture the banding, in my opinion, was much worse. In the end, looks like I have a very noisy TIA, and specifically the Tsync from Pin 2. 1) First problem is that when playing 7800 games the Tsync line would only decrease in amplitude to about 0.8V, which is right at the cusp of TTL logic and may causing problems with U3. So I added a resister to drop the peak-to-peak down to 0.4 V, but still keep a valid Tsync range for 2600 games. 2) Second problem was a ~0.5Mhz ripple on Tsync when the signal is high and was polluting the 74LS32 (U3) signal. After some experimentation, I found that tying a 10 nF cermanic cap to ground from Pin 3 of U3 filtered out a large portion of the noise. It was definitely a journey, but I'm quite happy with the result. There is still some minor (very minor) flicker left that I'll likely tune out with additional caps (looking at Pins 6, 8 and 11 on U3). This 7800 definitely has it's own character but I believe it's been tamed.

I've managed to get my ASR733 system working and extracted quite a few 99/4a files that may be of interest - in particular the DSR descriptions mentioned above some time back. https://www.blunham.com/Misc/Texas/Mine/index.html Colin Hinson.

😎 102 550 Should’ve been a much better score, had three lives and over 100k going into the meteors and it was brutal, no way through on the first life, dead before making it down the screen on the second and two close calls and death shortly after. I started a couple of games resuming that level afterwards and made it through there clean every time! My controller is getting worse too, stuttering and more wild movements, like taming a stallion!

“I hate asparagus, but I don’t talk about it on asparagus.com.” - Shawn Drover

I don't believe it, tell him to put up or STFU!!!

I remember early 1984 as the time when 2600 carts underwent a dramatic price drop. I guess this was the result of what we later referred to as the "'83 crash". I remember in early '84 being very sick with strep throat. On way home from doctors, went to a toy store and parents bought me fully boxed Super Breakout for $5. Probably at the same time a year earlier, that game was probably at least $15-$20.

Hey, just wanted to let you know that ti99iuc and I finished up the user manual for Atlantis in case you wanted to add it to the 'Shelf. The PDFs for the manual and cartridge lable can be download on GitHub here: https://github.com/CheungChang7/TI99_HOMEBREW/tree/main/ATLANTIS/DOCS Or you can grab them below. ATLMAN.pdf Atlantis Cart Label with cut lines.pdf

@ti99iuc and I finished up the manual for Atlantis. It can be accessed on GitHub here: https://github.com/CheungChang7/TI99_HOMEBREW/tree/main/ATLANTIS/DOCS Along with the files for the cartridge label. The files can also be downloaded below for convenience. I want to thank ti99iuc for creating the manual cover and cartridge label as well as helping me to get the manual good enough for publication ATLMAN.pdf Atlantis Cart Label with cut lines.pdf

I remember buying most of my 2600 games in the early 80s from Circus World, a toy store in our mall. They used to do a weekly ad in the local newspaper, and was always so excited to see that. Defender is one I really remember- $34.99! So expensive, I mowed tons of lawns back then.

GenXGrownUp has put up a really interesting interview with Gary Kitchen who did the 2600 port of Donkey Kong (the DK discussion starts at 5:42): Like Jennell, Gary makes it clear that developers were not asked to shank the ports, there was no Coleco conspiracy. Instead, the focus was on time to delivery and ROM size. Specifically, development needed to be complete in May '82 in order for production to be done by September, and the games to be available in the run up to Christmas. Further, Gary suggests that even if he had a larger ROM, he might not have been able to do much more in the 90 days he had for development. I suspect that, if he was still around, Frank Johnson might empathize with Gary's experience. The importance of ROM space is something that should not be forgotten when comparing DK ports. On the Colecovision, DK was originally a 24KB game written in Pascal. This compares with 4K decles (5KB) on the Intellivision and 4KB on the 2600. Therefore, it's not surprising that content was cut on the Inty and 2600 versions. I believe the Coleco version was reworked in assembly later, reducing the size to 16KB with no loss of functionality. This potentially shows the overhead of using a high level language, that more ROM space might have been traded for a shorter development time on the Colecovision version, and the efficiency improvement that more development time and experience can bring. So as a really naive comparison, even in it's optimised, 16KB form, Colecovision DK effectively had more than 5KB of ROM space per level, as compared with 2.5KB on the Inty and 2KB on the 2600.