Figuring Out Yars’ Revenge Code From Its Graphics

What is Set Side B about? We talk about old arcade and NES games, Nintendo things, weird gaming-related videos, ancient MMORPGs, and other weird and idiosyncratic things largely as they inspire us, much as how beta particles and gamma rays inspire random atoms as they pass through them, causing mutations and cancers along the way. (Alpha particles are too bulky to pass through, but that’s really just highly energetic ionized helium anyway!)

One foundational aspect of what we choose to highlight, though, are the extremely technical things, and wow, in that regard today’s link delivers. The brilliant Youtube channel Retro Game Mechanics Explained, which appears here semi-frequently, did a video on the Atari VCS/2600 game Yars’ Revenge that has to be seen to be believed, if not always quite understood.

It’s been random floating game knowledge for a while that the “Neutral Zone” area in Yars’, a flashing and coruscating band of lights that serves as something of a safe zone for the player’s bug, was the direct result of reading the game’s own code out of memory translated and displayed on screen. After all, machine language opcodes are just data, and the VCS has such a hugely limited address space that any reuse of that data is helpful.

RGME went through the graphics displayed on-screen and tried to see how much of the game’s code could be pieced together using it. The answer was, a fair bit, but not all. The process is really the most interesting part about it. Here it is:

Of particular note, the top comment on the video (because it got pinned there by RGME) is from Yars’ Revenge creator Howard Scott Warshaw himself!

In passing, let me just comment for a moment on what a weird phenomenon Yars’ Revenge is? It’s the best-selling original (non-port or license) piece of software for the old Atari. It’s such a weird artifact. It’s not a traditional style of game design. It’s got atmosphere, and strangely evocative sound. And it has that odd easter egg that can just outright end your game if you’re not careful. It really feels like an object of its time, that couldn’t have both come about and be as popular as it was in any other age. It didn’t inspire many imitators. But, it did come about, and it was popular, and I’m glad that’s true.

I watch this video and I wonder that it seems targeted so directly at me personally, that I wonder if anyone else might enjoy it at all. But then I look at its view count and see it’s approaching 200 thousand in around two weeks, so someone else out there must like it too. So: please watch the video, if you care about bits and bytes, opcodes and operands, and Exclusive-Ors. Or want to learn about those things. If neither is true for you, I’m sure there’ll be something more to your tastes tomorrow.

Reverse Engineering Game Code from the Neutral Zone in Yar’s Revenge (Youtube, 41 minutes)

Atari Archives Covers VCS Pac-Man

This is a big one. Youtube channel Atari Archives usually makes videos that average around 16 minutes in length, with the occasional entry that goes up to twenty or, once in a while, even thirty minutes. Their entry on Atari VCS/2600 Pac-Man, the infamous title that many claim destroyed the video game market in the US in 1983, goes for 38 minutes. (Their side episode on the Bally Astrocade is 48 minutes long, but it covers the history of an entire platform.)

The video’s states a thing that I have long suspected: Atari 2600 Pac-Man did not itself destroy the game console industry. I also don’t think the other prime suspect, Atari E.T., did it.

If you pressed me, I’d think that both may have been contributing factors, but only as part of a larger trend: stores shelves were inundated with a flood of games at the time, as lots of companies jumped heedlessly into the software market. The opportunity created by Activision, which was famously founded by Atari programmers upset by how they were treated there, which established in court that it was legal for competitors to make their own software for a company’s system, was soon taken advantage of by dozens of other outfits. For every Activision and Imagic, however, there were a bevy of Apollos and Froggos, whose mostly terrible games, in that pre-Internet era, looked about as good to a typical buyer.

Plus, I think there was an element of the bursting of a fad at that time. The success of the Atari 2600 was possibly unsustainable. Even the widely ridiculed VCS port of Pac-Man sold over seven million copies, a sales record that wouldn’t be matched until the middle of the NES’s life.

For more information on the game, and its many other contemporary ports, I refer you to the video.

Atari Archives: Episode 66, Pac-Man (38 minutes)

News 12/28/22: ASCII Dwarves, eShop Shutdowns, Ecco the Dolphin

“We scour the Earth web for indie, retro, and niche gaming news so you don’t have to, drebnar!” – your faithful reporter

Computer issues kept me from filing last week’s report. That is the reason. It is not true that I got so drunk at a Globmas Party that my chemical composition was 50% alcohol. Don’t listen to those rumors! Let us begin.

Image from PCGamesN

Dwarf Fortress’ Steam Edition is still the toast of the gaming blogoglobe! A recent update lets you use the original version’s ASCII graphics instead of the high-falutin’ new pixel art skin. So proclaimeth Ian Boudreau at PCGamesN!

It’s funny. Corbin Davenport writes an article at How-To Geek titled Atari’s New Gaming Console Isn’t Dead Yet. But it’s URL is: https://www.howtogeek.com/855757/ataris-new-gaming-console-is-dead/ Don’t you love how URL slugs can reveal a piece’s working title? The article itself is more about how it’s mostly dead, so someone call Miracle Max.

Gavin Lane at NintendoLife discusses the upcoming shutdown of the 3DS and WiiU eShops. You haven’t been able to add funds for a while through the stores, although you could still add them using the Switch’s shop then use that money to buy there. The piece mentions that Nintendo has been almost anxious to close the shops, due to poor sales of the WiiU. You’ll still be able to download purchased software… for a while.

Also at NintendoLife, Liam Doolan interviews a couple of people at Wayforward about River City Girls 2! It turns out that planning began almost immediately after RCG1 wrapped up.

Tom Ivan. Video Games Chronicle. Microsoft and Activision have filed responses to the FTC complaint about their merger being anti-competitive. Creatures of my species are capable of merging together into one blobby whole, which is admittedly quite fun on a boring Saturday night, but none of us are corporations that control massive segments of the console gaming market!

Related, Jezz Corden of Windows Central reports that Microsoft is claiming that Sony’s influence will prevent four specific games from ever reaching the Xbox console platform: Final Fantasy VII Remake, Final Fantasy 16 (shouldn’t that be XVI?), Silent Hill 2 Remake, and Bloodborne.

And finally, at The Ringer, M.D. Rodrigues writes a long piece about the legacy of the Sega Genesis Ecco the Dolphin games.

Romhack Thursday: Astro Smash ‘N’ Blast!

On Romhack Thursdays, we bring you interesting finds from the world of game modifications.

Most of the things we post here are game hacks. That is, something that has been modified from a published game. Hacking games is not illegal, but the process that some people usually use to obtain the roms themselves may be somewhat questionable. Well not for the subject of this week’s article: it’s 100% homebrew, created from scratch and unencumbered by such considerations! It runs on NES hardware (or an NES emulator), but technically speaking what we have here is more of an indie game on classic console hardware more than a hack.

It’s also an unusual subject for a 2022 indie game. You’ll find all kinds of hacks to, say, put silly characters into Super Mario Bros., but a remake of an Intellivision game, and one with an Atari port that is very much its equal, and porting those games to the NES-that’s unusual enough to merit discussion, even if the game itself is very simple.

Astrosmash! (with the exclamation point) was a very popular game for the Intellivision. I heard it was originally intended to be an Asteroids-style game, with rocks that split into pieces when shot, but turned out to be interesting translated to a Space Invaders-style missile base game, where your ship is stuck to the bottom of the screen shooting at targets falling from above. Astroblast! was released by M-Network (Mattel’s label for publishing games for competing systems), and was a very similar game for the Atari VCS/2600, but actually improved on the original in two ways: it can be played with either the joystick or paddle controller. It’s the only game for the VCS like that! Both control schemes are fun, although experts can probably play much better with the paddle, due to both its faster and more precise movement. And, it’s extremely fast! The sheer pace of the VCS Astroblast is so much greater than the Intellivision Astrosmash that it kind of demonstrates why VCS games tend to be more engaging than Intellivision games: it wastes no time with an easy ramp up in difficulty, but starts faster than almost any other game, and only gets harder from there. It’s simply exhilarating!

The way it works is like this. Rocks, Pulsars and Spinners fall from the sky, and your ship tries to shoot them before they hit the ground. You get points for shooting things, but lose points for things that get past you. Rocks come in two sizes (smaller ones have higher point values), but only kill you if they hit you. Big rocks break apart into small rocks when stuck. Pulsars home in on you as they fall, which makes it more likely they’ll hit you, but also means they’re easier to shoot. The most dangerous items plummeting towards you though, by far, are the Spinners. You must shoot Spinners, you don’t just lose points if one lands but a life. Small Spinners are your greatest enemy, since they’re also hard to hit. There’s also UFOs that harass you, which pass by horizontally and drop bombs on you.

Here is a short game of Astroblast, to give you a sense of how it works. Notice how fast it is. Know that this is nowhere near as fast as it gets. It is my kind of game:

As you score gets higher, the background color changes, and the game gets faster. You get extra lives every 1,000 points, and you start with ten, far more generous than most arcade-style skill tests from that time, but you need all those lives because you’re constantly dying. Difficulty is determined by score, the more points you have the faster it gets. Because you lose points as well as gain them, and because the speed is balanced right at the edge of human reaction time, players tend to play until they reach a difficulty score boundary, where only nearly-inhuman focus, and lots of practice, can push you beyond it. Astroblast will push your playing skills to the very limits.

Astro Smash ‘N’ Blast is an homage to these two games. It takes the same form, your ship at the bottom shoots upwards at an endless wave of plummeting targets, Rocks, Pulsars and Spinners. (There are no UFOs in this version.) There’s fewer things falling, but the game is a bit more precise about hitting small targets. Pressing the Select button turns on autofire, which you’ll probably want to use, to avoid compressing your thumb tissue into a singularity with rapid frantic tapping.

Rocks don’t split in two in this version, but otherwise it plays a lot like VCS Astroblast. Small Spinners are particularly difficult targets to hit, and must be aimed at precisely.

This version takes on a bit of inspiration from Pac-Man CE, in that in addition to having limited lives, you have a time limit. You can earn extra time by hitting +30 second targets that pass by horizontally, and you can regain hits on your ship by hitting passing 1UPs. These are the only bonuses; unlike the originals, you don’t get extra ships from points at all. Although the game ends if you run out of time, chances are great that you’re going to lose all five of your lives before then.

As in Astrosmash/blast, as you ascend to tougher difficulties, the screen’s background color changes. You probably won’t see the later levels though without a lot of practice. Astro Smash ‘N’ Blast offers a level of challenge rarely seen in most games. I prefer games like this, with a strong element of chaos, to more typical modern examples of high challenge, like bullet hell shooters and rhythm games. I think the essence of the super fast video game is in randomness, not memorizing levels and playing them almost by rote but in reacting instantly to dynamic situations, and that’s why I like all the Astro-style games.

I am left wondering what inspired Double Z to look to old Intellivision and Atari games for inspiration. They were released when I was a small child; had Double Z even been born yet when the Astro games were on store shelves? For whatever reason they made it, I am glad they did. Games like this don’t come around often any more, and I intend to put in some solid practice on it.

Astro Smash ‘N’ Blast, for NES (romhacking.net)

How David Crane Got Good Music Out Of The Atari VCS For Pitfall II

Back in 2013, David Crane chimed in on a thread about Pitfall II. The Atari VCS (a.k.a. 2600) was not known for the quality of its music. For sound effects, especially noise effects like blasts and booms, it was fine, but its TIA chip didn’t have the frequency resolution to produce every musical note precisely, meaning some of it notes would sound a bit off.

Pitfall II’s music, some of the best on the system in the classic era

There was technically a way to produce almost arbitrary waveforms, though like many techniques on the system it was processor-intensive. It involved changing the volume on one of its sound channels in real time to simulate the waveform of the sound you wanted to make. That was fine so long as you didn’t need the processor to do anything else, and sadly, on the VCS, just displaying graphics relied heavily on the processor.

Pitfall II, VCS/2600 version. Image from Mobygames.

David Crane managed to get decent polyphonic music out of the VCS by using Pitfall II’s DPC chip, which Crane created himself, as a co-processor that figured out the right values to set the volume to produce the mixed waveform for the music at a specific time, which the machine’s overworked 6507 CPU could then read and send to the right volume register in the TIA every scanline. The process is explained (to the understanding of a sufficiently technical frame of mind) here. I think I understand it myself!

The fact that David Crane is still around, and so willing to discuss the many tricks he came up with to make his games, is a great blessing, as is the existence of the AtariAge forums themselves, which are a trove of classic gaming information.

Nowadays this technique has been refined and utilized in homebrew cartridge productions. A particular standout is the music from Champ Games’ version of Mappy, which is frankly amazing. Check it out:

News 7/24/22: Knockoff Internet Lego

“We scour the Earth web for indie, retro, and niche gaming news so you don’t have to, drebnar!” – your faithful reporter

At TechRadar, Jeremy Peel is set on telling us about Rogue Mage, an expansion to the Gwent card roguelite game set in the Witcher universe. Hey! Did you know there are roguelike games that don’t involve building a deck? It’s true!

At NintendoLife, Jim Norman (hey! a new guy!) informs of a blatant knockoff of beloved indie perennial Mini Metro on the Switch eShop. Boo! Hiss! Burble! Splorch! It’s like some folk on your planet were born without shame glands.

Jorge Jiminez at PC Gamer tells us the FCC is trying to get everyone in the US good internet. As a one-celled life form from a distant planet I don’t have much stake in the matter, but I can be happy for people by proxy, and do you know why? It’s because I’m not a jerk, drebnar! Glad to see the agency is trying to recover from that horrid stance against Net Neutrality back during what I understand Earth people call “the years of the carrot monster.”

Meow

At Kotaku, John Walker (another new name!) sounds a harsh note about Stray, a game that most of the internet has enthused over, by mentioning how, while it starts with you playing as a very cat-like cat, by the end you’re also playing as their robot companion a lot, and shooting things all zappy zappy, and doing a lot of video game stuff. It still doesn’t sound at all like a bad game, but just, something a bit different by the end than people may expect?

Bunches of people have been talking about the new Lego set that lets you build a plastic Atari 2600, our link to the subject is CapnRex101 at Brickset, a Lego fansite. It looks like a great model that is full of detail, although notably it retails for $240. For that price you could probably get your hands on a real VCS, although at the cost of it being actually playable, at least if you have a CRT lying around. But if you were going to go that far, you’d probably just look into getting a Flashback.

Fixing E.T.

It’s nine years old, but I’m amazed by how few seem to know of these old projects that litter the internet, and this is one that’s definitely worth revisiting.

When people talk about reasons for the Great Game Crash of 1983 (which, it should be remembered, was mostly a crash in the U.S., other countries didn’t suffer much loss in popularity), one reason sometimes given was the lack of quality of one specific game: Howard Scott Warshaw’s E.T. The Extra-Terrestrial, for the Atari VCS/2600. (That’s not really the point of this post. For more of this, seen the Addendum, below.)

I should emphasize that it was easy to get frustrated by E.T. Its development was rushed so that it could be in stores in time for the 1982 Christmas season. Warshaw’s previous work Yars’ Revenge was a huge hit for Atari, but its successor, Raiders of the Lost Ark, is possibly a bit too experimental. I think E.T. is a better game than Raiders, it’s easier to learn certainly, but it has some definite issues that make it very frustrating to play.

There were a number of issues, but the biggest by far was that it was extremely easy to fall into the many pits that dotted the landscape of the game’s version of Earth, and after floating up out of one, it was just as easy to immediately fall back into one again. You could fall into a pit merely from changing screens in the wrong location.

Back in 2013, a user in the AtariAge forums using the handle recompile produced a hack to fix the game’s problems, including this one. They made a page that the hack from which could be downloaded, and explained, in great technical detail, how it had been made. The result has slightly worse graphics than the original, but is much more playable, and reveals that there is a very interesting game hidden beneath the rushed product mandated by Atari’s managers. Not only is the page and his work still up now, nine years later, but so is the AtariAge thread he made.

Remember: a delayed game is eventually good, but a bad game is bad until someone with enough time, energy and technical know-how takes it upon themselves to fix it, which in E.T.‘s case was about 31 years from its release.

Addendum

Was E.T. the real reason for the U.S. crash? Honestly, I’m dubious. It’s likely a contributing factor, but a slight one. But the fact that it can’t be ruled out, and probably helped a little, makes it something that many writers can point to without much fear of contradiction. It’s the way many narratives are built.

But there were plenty of good games, by the standards of the time, to offset the fortunes of any single title. A more likely explanation was a deluge of bad games, and a market oversaturated by them produced by companies looking for a quick buck, so that unless a consumer had done their research, it was difficult to separate the worthwhile purchases from the cash grabs.

Video games had, almost overnight, turned into a billion-dollar business. For a few years, specifically 1978 to 1982, the success of arcades, and of the Atari VCS and a number of excellent games for it, tantalized a nation. For a brief period, almost everyone sold game cartridges. I remember seeing them on the racks of drug stores during that time.

Then, almost as suddenly as it had risen, it collapsed. No one knew which games were good and which were bad. Even the good ones were pretty expensive: a $30 game in 1982 was nearly $90 in today’s (2022) money. All of those stores that had jumped on the bandwagon were left with piles of unsold inventory. Console gaming died out almost completely for a few years, until the arrival of the NES, and some canny moves by Nintendo of America, resurrected the industry in the land of its birth.

Homebrew Atari VCS/2600 Arcade Ports

The long-running Atari fansite AtariAge sells a number of carts that run on classic Atari VCS systems that make it do things you might not expect that system could do. Some of the most impressive of these are remakes of classic arcade games that go far beyond what was possible at the time. A number of these were developed by Champ Games. Here are links to a number of videos showing them off, although sone of the may not currently be in their store:

Galagon” – Wizard of WorZoo KeeperAvalancheScrambleSuper CobraMappy (especially this one!)

A few others, not from Champ Games: Aardvark (Anteater) – Venture ReloadedSpace Rocks (Asteroids) – Star CastlePac-ManDraconian (Bosconian)

Video: Atari Archive

Atari Archive is one of those projects that seeks to document every game released for some platform. In this case, it’s for the Atari VCS. That’s the original one, the real one, CX2600, not the one made by the company that currently wears the skin of the old Atari like a gruesome shroud.

The Atari VCS/2600 wasn’t the first programmable video game console, but it was certainly the most popular early console. (I had my own look at a few interesting examples of its software in a book of my own.)

Atari Archive is currently up to Episode 57, on Kaboom! Episodes tend to be in the 10-15 minute range, making it easy to find out about specific games in a timely fashion. Here are a few popular games to get you started:

#56: Warlords#54: Missile Command#33: Adventure#32: Space Invaders – and, of course, #1: Combat