David Horne's 1K Chess on the ZX81 (2001) • Hacker News Board

Re: David Horne's 1K Chess on the ZX81 (2001)

#11

Post by pyrois » Thu, Mar 05, 2015, 4:57 PM UTC

StavrosK wrote: post #2

Why does the author say "memory" when he means "disk space"? Or does he actually mean "memory", as in "RAM"? In that case, why would the size of the executable matter?

"Memory" means RAM, here.

As for why the size of the executable matters, you needed to have the entire executable in RAM before you could actually execute it. That's not so true these days, but it was back in the good ol' days* when you hooked tape cassettes up as your external storage.

* Get off my lawn!

Re: David Horne's 1K Chess on the ZX81 (2001)

#12

Post by pyrois » Thu, Mar 05, 2015, 5:00 PM UTC

luma wrote: post #7

If you can't castle, you can't promote a pawn, and you can't en passant, it isn't chess.

True, but even "Chess lite" in 672 bytes is mind-blowing.

Re: David Horne's 1K Chess on the ZX81 (2001)

#13

Post by ColinWright » Thu, Mar 05, 2015, 5:01 PM UTC

StavrosK wrote: post #9

ctdonath wrote: post #4

Earlier quoted context omitted.

There was no "disk" on a ZX81. Storage was audio cassette tape. The size of the executable mattered because it all had to fit in 1024 bytes RAM (no "K", no "M", certainly no "G") with all video & operating system memory.

Oh wow, I didn't know that, thanks. By the way, to whomever downvoted a legitimate question: Nice.

I didn't downvote you, but you asked a question the answer to which is easily available with the most trivial of web searches. You assumed he meant "disk space", assuming the author made a mistake when you could easily have checked and not asked the question here.

In some sense, it's not a legitimate question for this context.

Re: David Horne's 1K Chess on the ZX81 (2001)

#14

Post by pavel_lishin » Thu, Mar 05, 2015, 5:12 PM UTC

luma wrote: post #7

If you can't castle, you can't promote a pawn, and you can't en passant, it isn't chess.

You are welcome to add these things; we'll give you a generous extra 100 bytes.

Re: David Horne's 1K Chess on the ZX81 (2001)

#15

Post by stpe » Thu, Mar 05, 2015, 5:13 PM UTC

3327 wrote: post #8

Holy smokes... blown away. 1K RAM? less then most email's we write... Now'a days rockstars and Ninja's are the glorified ruby guys who "seemingly" do Ruby/django magic... This is what counts...This is the real deal...

On this topic, check what was done (and still is, to some extent on the homebrew scene) on the Atari 2600 with 128 bytes of RAM and no framebuffer.

Re: David Horne's 1K Chess on the ZX81 (2001)

#16

Post by pfortuny » Thu, Mar 05, 2015, 5:16 PM UTC

3327 wrote: post #8

Holy smokes... blown away. 1K RAM? less then most email's we write... Now'a days rockstars and Ninja's are the glorified ruby guys who "seemingly" do Ruby/django magic... This is what counts...This is the real deal...

Now you only have less than 800 bytes left. And counting.

Re: David Horne's 1K Chess on the ZX81 (2001)

#17

Post by GregBuchholz » Thu, Mar 05, 2015, 5:18 PM UTC

Olivier Poudade has recently written and even smaller version of the chess program, clocking in at 468 bytes:

http://olivier.poudade.free.fr/

http://www.bbc.com/news/technology-31028787

Re: David Horne's 1K Chess on the ZX81 (2001)

#18

Post by moron4hire » Thu, Mar 05, 2015, 5:26 PM UTC

3327 wrote: post #8

Holy smokes... blown away. 1K RAM? less then most email's we write... Now'a days rockstars and Ninja's are the glorified ruby guys who "seemingly" do Ruby/django magic... This is what counts...This is the real deal...

Weeeell...

The entire point of computers is to be able to do work that would be too tedious for humans. Computers exist so people can be lazy.

Making better programming languages so programmers can be lazy is kind of the whole point of the job.

Re: David Horne's 1K Chess on the ZX81 (2001)

#19

Post by JonathonW » Thu, Mar 05, 2015, 5:26 PM UTC

stpe wrote: post #15

3327 wrote: post #8

Holy smokes... blown away. 1K RAM? less then most email's we write... Now'a days rockstars and Ninja's are the glorified ruby guys who "seemingly" do Ruby/django magic... This is what counts...This is the real deal...

On this topic, check what was done (and still is, to some extent on the homebrew scene) on the Atari 2600 with 128 bytes of RAM and no framebuffer.

Of course, the Atari (unlike the Sinclair in the OP) executed code directly from the cartridge-- you didn't have to fit your whole program into that 128 bytes of RAM. Atari cartridges could be up to 4kB, or 32kB with bank switching, which is downright roomy for the era.

Re: David Horne's 1K Chess on the ZX81 (2001)

#20

Post by VonGuard » Thu, Mar 05, 2015, 5:28 PM UTC

Just for the record, the Atari 2600 also had a chess game with AI. It also had only 1024 bits of RAM, but it had access to all of it because there was no OS or underlying hardware support, like in the Speccy. So while this is definitely amazing, the 2600 version is very close in the "insanely well coded" category, especially because the 2600 had some SERIOUSLY quirky hardware to deal with. For example, on the 2600, you could only draw half the screen's background: the other side had to be a mirror image. Additionally, the columns of pixels that you drew on the screen were enumerated, to the halfway point on the screen as follows:

12345678,87654321,1234

So you were drawing forward, backward, then forward again, and that only got you half the screen!