Bankswitching

[yllawwally]

What where the first games to use each of the different bank switching schemes?

[killersquirel]

Asteroids was the first game to use bankswitching on the VCS.

[Cynicaster]

Can somebody describe in layman's terms what bankswitching is, exactly? I think I kinda-sorta get what it is, but what I don't really understand is why it seems to be talked about retrospectively as though it was so ingenious. From the sounds of it, it was an obvious way to manage a limitation of the VCS hardware.

 

It's almost like:

 

Person A: "I sure wish I could get this candle to burn more quickly."

 

Person B: "Why don't you light it at both ends?"

 

Person A: "You're a genius!"

 

Obviously, I'm not a programmer, so maybe I just don't appreciate the achievement.

[+Random Terrain]

Can somebody describe in layman's terms what bankswitching is, exactly? I think I kinda-sorta get what it is, but what I don't really understand is why it seems to be talked about retrospectively as though it was so ingenious. From the sounds of it, it was an obvious way to manage a limitation of the VCS hardware.

The batari Basic page seems to have a pretty good description in the first paragraph:

 

randomterrain.com/atari-2600-memories-batari-basic-commands.html#bankswitching

 

 

This page tells even more:

 

gamasutra.com/view/feature/3766/atari_the_golden_years__a_.php?print=1

 

Getting the Asteroids coin-op to fit into a cartridge for the VCS was not an easy task. Brad Stewart, the programmer responsible for the VCS version of Breakout, took on the task, and it was not an easy one. Fitting all the Asteroids graphics and game play into a standard 2K cartridge was impossible. In fact, even a 4K cartridge could not hold it all.

 

"Asteroids needed the 8K, though. After the game was complete, Bob Smith and I spent some time using every trick we knew to try to get it into 4K, but it just... would... not... fit!" ^cxc

- Brad Stewart

To get access to 8K, Stewart used a newly devised scheme called bank-switching (originally created for the VCS Basic Programming cartridge) that allowed a programmer to access multiple 4K banks of memory. This was a breakthrough for the VCS.

 

"The present invention provides a bank switching memory and method for increasing the number of individual address locations that can be addressed in a digital system. The present invention expands the available memory space beyond that capable of being addressed by a conventional addressing having a unique memory location associated with a unique address. Specifically, the invention is used to expand the number of ROM memory locations contained in the game cartridge of a video game system without requiring additional address lines."

- Carl J. Neilson, Bank Switchable Memory System patent, filed May 7, 1981

Bank-switching opened up the VCS to a whole new world of crisper and more elaborate graphics. It made Asteroids possible on the VCS, which in turn would make Atari VCS the need-to-have item for Christmas 1981.

 

[Mr SQL]

Can somebody describe in layman's terms what bankswitching is, exactly? I think I kinda-sorta get what it is, but what I don't really understand is why it seems to be talked about retrospectively as though it was so ingenious. From the sounds of it, it was an obvious way to manage a limitation of the VCS hardware.

 

It's almost like:

 

Person A: "I sure wish I could get this candle to burn more quickly."

 

Person B: "Why don't you light it at both ends?"

 

Person A: "You're a genius!"

 

Obviously, I'm not a programmer, so maybe I just don't appreciate the achievement.

 

Cynicaster,

follow the link in my signature where I teach Assembly using action figures, JCVD covers bankswitching exactly as you've described:)

[+Gemintronic]

Can somebody describe in layman's terms what bankswitching is, exactly? I think I kinda-sorta get what it is, but what I don't really understand is why it seems to be talked about retrospectively as though it was so ingenious. From the sounds of it, it was an obvious way to manage a limitation of the VCS hardware.

 

It's almost like:

 

Person A: "I sure wish I could get this candle to burn more quickly."

 

Person B: "Why don't you light it at both ends?"

 

Person A: "You're a genius!"

 

Obviously, I'm not a programmer, so maybe I just don't appreciate the achievement.

 

The Atari 2600 can only see 4k worth of storage space for the game program. In order to have more game they put extra hardware into the cart that switches to another 4k of game information. The hard thing about this is that EVERYTHING from that first 4k of information is no longer present.

[Nukey Shay]

Actually, that would depend on the type of bankswitching implemented. They could be made as complex as needed...swapping out individual portions of the 4k rom range that the console can only address. BTW I thought that the "standard F8" VCS banking was originally developed for Chess (but not used there)? BASIC Programming was a pet project of Robinett's.

[+Random Terrain]

. . . originally developed for Chess (but not used there)?

That's what I always read. Don't know why BASIC Programming is given credit in that article. Maybe the person writing it was confused or drunk or high or knows something we don't.

[freewheel]

Can somebody describe in layman's terms what bankswitching is, exactly? I think I kinda-sorta get what it is, but what I don't really understand is why it seems to be talked about retrospectively as though it was so ingenious. From the sounds of it, it was an obvious way to manage a limitation of the VCS hardware.

 

Almost every technological achievement looks obvious in hindsight, especially decades after the fact. You could just as easy use the "obvious" comment towards television, computers, cars...

 

Bankswitching is basically a technique to make more ROM available than you have address lines for. The implementations seem obvious now, but HOW to go about doing them was anything but obvious at the time. You have to also understand computing in the late 1970s. People just assumed a computer was built to deal with X, so sometimes even the thought of dealing with X+1 just never occurred to anyone. Hell, multitasking in its various flavours seems obvious to us now, but the sheer idea was considered radical at one point. Bankswitching is a lot like this.

 

It's the same reason older cars don't always have drink holders, even though today they're "obviously needed". And it's the same reason we weren't all posting on online forums in 1986, even though millions owned computers and the phone system was everywhere. The Internet just took enough "obvious" ideas to be put together.

[Mr SQL]

 

It's the same reason older cars don't always have drink holders, even though today they're "obviously needed". And it's the same reason we weren't all posting on online forums in 1986, even though millions owned computers and the phone system was everywhere. The Internet just took enough "obvious" ideas to be put together.

Huh? Many of us were posting on forums, chatting with instant messaging, playing online RPG's and downloading games and demos in the 80's; some of us wrote the software facilitated this Only difference then and now you had to hang up and dial the next IP by hand

 

And today's cars don't all compare so favourably IMO; some are missing cigarette lighters and some are ergonomic just for tiny folk

[freewheel]

Huh? Many of us were posting on forums, chatting with instant messaging, playing online RPG's and downloading games and demos in the 80's; some of us wrote the software facilitated this Only difference then and now you had to hang up and dial the next IP by hand

 

 

That's why I said "we weren't all".

 

To some of us, being online seemed natural and obvious and to some degree necessary. But the real full build out took decades, because no one saw a point (or even understood how to scale some of the infrastructure). And yet today, it's bleedingly obvious how to do it, why we do it, and most people can't imagine our society without it.

 

Bankswitching only looks obvious in hindsight. Like many if not most technologies.