4 ms·

I was lucky enough to see this talk in person at the Vintage Computer Festival West this year. One of the absolute highlights (timestamp https://youtu.be/_1jXE

by gfaure 5y ago

I was lucky enough to see this talk in person at the Vintage Computer Festival West this year. One of the absolute highlights (timestamp https://youtu.be/_1jXExwse08?t=1903 https://youtu.be/_1jXExwse08?t=1903) was the incredible work on a custom disk loader that increased the throughput from 400 bytes/s to 7.5 kB/s! A writeup of that optimisation work, which was only published in 2013, can be found here: https://www.linusakesson.net/programming/gcr-decoding/index.php https://www.linusakesson.net/programming/gcr-decoding/index....

crispyambulance 5y ago
The same person also wrote "The TTY Demystified" also a very good read: https://www.linusakesson.net/programming/tty/index.php https://www.linusakesson.net/programming/tty/index.php
buescher 5y ago
"In order to shave off a cycle from every instruction that modifies another one, the entire loop will be placed in the zero-page." Oh wow.
- TacticalCoder 5y ago
  If you like that kind of stuff, here's the 256 bytes (!) C64 intro "A mind is born" and its technical explanation... It's using that same zero-page trick: https://linusakesson.net/scene/a-mind-is-born https://linusakesson.net/scene/a-mind-is-born I have no words... These coders are amazing!
c64d81744074dfa 5y ago
> increased the throughput from 400 bytes/s to 7.5 kB/s Since then someone has come up with yet another custom disk loader that's more than twice as fast as that one! https://csdb.dk/release/?id=197710 https://csdb.dk/release/?id=197710 It's incredible that people are still pushing the limits of the stock C64 system these days...
- TMWNN 5y ago
  >It's incredible that people are still pushing the limits of the stock C64 system these days... It's staggering to think that such a thing is possible on the stock hardware, just as it is staggering to consider that 1024 colors on a stock IBM PC with CGA is possible as the 8088 MHz demo has proven. What would have happened if an IBM engineer in 1981, or Commodore KERNAL developer in 1982, had had the necessary insights to come up with such innovations? CGA and the early IBM PC's reputations as a poor computer for games would not have come to pass. The C64 and 1541 would have been viable for things other than games. Of course, the PC standard took over the world despite CGA's four garish colors. Of course, the 64 was the dominant home computer of the 1980s regardless of the need for a third-party fast loader. But one can't help but wonder what more could have been done.
  - PostThisTooFast 5y ago
    "CGA and the early IBM PC's reputations as a poor computer for games would not have come to pass" Yes it would. The IBM had no hardware sprites, no fine scrolling, and no sound capability to speak of. It was obsolete the day it went on sale. The Ataris crushed everything else on the market in terms of capability (and certainly value for the money) until the C64 largely ripped it off and provided competitive capability.

by gfaure 5y ago

crispyambulance 5y ago

The same person also wrote "The TTY Demystified" also a very good read: https://www.linusakesson.net/programming/tty/index.php https://www.linusakesson.net/programming/tty/index.php

buescher 5y ago

"In order to shave off a cycle from every instruction that modifies another one, the entire loop will be placed in the zero-page." Oh wow.

TacticalCoder 5y ago
If you like that kind of stuff, here's the 256 bytes (!) C64 intro "A mind is born" and its technical explanation... It's using that same zero-page trick: https://linusakesson.net/scene/a-mind-is-born https://linusakesson.net/scene/a-mind-is-born I have no words... These coders are amazing!

c64d81744074dfa 5y ago

> increased the throughput from 400 bytes/s to 7.5 kB/s Since then someone has come up with yet another custom disk loader that's more than twice as fast as that one! https://csdb.dk/release/?id=197710 https://csdb.dk/release/?id=197710 It's incredible that people are still pushing the limits of the stock C64 system these days...

TMWNN 5y ago
>It's incredible that people are still pushing the limits of the stock C64 system these days... It's staggering to think that such a thing is possible on the stock hardware, just as it is staggering to consider that 1024 colors on a stock IBM PC with CGA is possible as the 8088 MHz demo has proven. What would have happened if an IBM engineer in 1981, or Commodore KERNAL developer in 1982, had had the necessary insights to come up with such innovations? CGA and the early IBM PC's reputations as a poor computer for games would not have come to pass. The C64 and 1541 would have been viable for things other than games. Of course, the PC standard took over the world despite CGA's four garish colors. Of course, the 64 was the dominant home computer of the 1980s regardless of the need for a third-party fast loader. But one can't help but wonder what more could have been done.
- PostThisTooFast 5y ago
  "CGA and the early IBM PC's reputations as a poor computer for games would not have come to pass" Yes it would. The IBM had no hardware sprites, no fine scrolling, and no sound capability to speak of. It was obsolete the day it went on sale. The Ataris crushed everything else on the market in terms of capability (and certainly value for the money) until the C64 largely ripped it off and provided competitive capability.