Linked by Thom Holwerda on Sun 17th Jul 2011 12:01 UTC
Hardware, Embedded Systems "Back in the 80s, the Commodore C-64 had an intelligent floppy drive, the 1541, i.e. an external unit that had its own CPU and everything. The C-64 would send commands to the drive which in turn would then execute them on its own, reading files, and such, then send the data to the C-64, all over a propriatory serial cable. The manual for the 1541 mentioned, besides the commands for reading and writing files, that one would read and write to its internal memory space. Even more exciting was that one could download 6502 code into the drive's memory and have it executed there. This got me hooked and I wanted to play with that - execute code on the drive. Of course, there was no documention on what code could be executed there, and which functions it could use." Very interesting. I'm most interested in how he describes others taking his work, and making it better. This would be impossible today, thanks to Microsoft, Apple, and other patent trolls.
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Slow?
by jack_perry on Sun 17th Jul 2011 15:38 UTC
jack_perry
Member since:
2005-07-06

Wasn't the C-64's floppy drive also infamous for how slow it was?

Reply Score: 2

RE: Slow?
by pgeorgi on Sun 17th Jul 2011 15:47 UTC in reply to "Slow?"
pgeorgi Member since:
2010-02-18

The bus was super slow. Part of the reason is that the chip in use was found to have an issue, so they had to do the protocol entirely in software.

FCopy and similar fast loaders improved over that last minute hack job by using improved timing and algorithms.

The 1571 in "burst" mode finally implemented everything the way it was originally intended - and was reasonably fast.

The nice thing about the drive family was its CPU: actually being able to control either side made improvements like FCopy possible

Reply Score: 3

RE[2]: Slow?
by Zbigniew on Sun 17th Jul 2011 16:38 UTC in reply to "RE: Slow?"
Zbigniew Member since:
2008-08-28

The bus was super slow. Part of the reason is that the chip in use was found to have an issue, so they had to do the protocol entirely in software.

Well said: "part" - since, as various "fastloaders" proved, even the relatively simple software-based solution could from the very beginning make the transferrate about 4-5 times faster (and not necessarily with a need to switch screen off during loading).

FCopy and similar fast loaders improved over that last minute hack job by using improved timing and algorithms.

...and by parallel cable connected via User-Port.

The 1571 in "burst" mode finally implemented everything the way it was originally intended - and was reasonably fast.

Yes, but one should add here, that faulty VIA 6522 has been replaced by CIA 6526.
Really a pity, that the problem couldn't be fixed by hardware change that several years earlier... but example of "JiffyDOS" shows, that improvement of data transfer routines in both C-1541 and C-64's kernels resulted in about 20x faster transfers, even while still using that faulty VIA 6522. It's a pity, that Commodore engineers were in hurry "back in the day", and were under pressure to "make it work at all", never mind its speed.

Reply Score: 3

RE[3]: Slow?
by JLF65 on Sun 17th Jul 2011 21:33 UTC in reply to "RE[2]: Slow?"
JLF65 Member since:
2005-07-06

With fastloaders, the C64 loaded from the floppy ALMOST as fast as the Atari 400/800/XL/XE did from cassette. ;)

Reply Score: 2

RE[4]: Slow?
by zima on Sun 17th Jul 2011 22:09 UTC in reply to "RE[3]: Slow?"
zima Member since:
2005-07-06

...as long as nobody breathed in the building and any heavy traffic outside was stopped, when a small Atari was loading a cassette ;)

Edited 2011-07-17 22:10 UTC

Reply Score: 2

RE[5]: Slow?
by JLF65 on Mon 18th Jul 2011 18:40 UTC in reply to "RE[4]: Slow?"
JLF65 Member since:
2005-07-06

Actually, the Atari was VERY robust with their cassette. It used FSK for the data, and was immune to almost any problem. I could pound my A410 on a wall during loading and it wouldn't miss a bit. ;) The REALLY cool thing about the Atari cassette is they used a stereo cassette, where one channel carried data (in FSK format as mentioned), while the other channel was mixing with the computer audio. This allowed educational cassettes to talk to the user while loading data from the cassette.

Reply Score: 3

RE[6]: Slow?
by zima on Tue 19th Jul 2011 02:26 UTC in reply to "RE[5]: Slow?"
zima Member since:
2005-07-06

Hm, weird. It's not merely something what I remember, "do not breathe" is the stuff of legends :p (maybe largely due to how this was happening with cheap late small Atari models and their peripherals, the ones which were fairly standard in "lesser" markets at the time when few places were already basically waaay post-A500; it seems that such markets were possibly served even by sub-standard machines, judging from few snippets at http://en.wikipedia.org/wiki/Atari_8-bit_family#Tramiel_era:_XE_ser... )

And my buddy who had both (small Atari and c64, no case of "holy war" ;p ) seems to remember the c64 tapes as faster (though not being sure of it; plus, "turbo" cartridges and tapes were standard for c64 while I don't think it was the case with Atari). Floppy would be obviously faster than that.

Edited 2011-07-19 02:33 UTC

Reply Score: 1

RE[7]: Slow?
by JLF65 on Wed 20th Jul 2011 21:31 UTC in reply to "RE[6]: Slow?"
JLF65 Member since:
2005-07-06

That's possible - the later hardware wasn't as good as the earlier stuff. My A410 was and still is a rock. The ONLY problem I've ever heard with the early cassette is the motor belt eventually wears out... like on all cassettes that use a belt. However, those early cassettes could use almost anything to replace the belt. I've seen people who used a rubber band as a replacement belt.

Atari might have skimped on the XL or XE model of the cassette, probably because they felt everyone would be using the floppy drive by that point. Unless you have some of those old cassettes, there certainly wasn't a financial reason to go with a cassette over a floppy. Back when I first got my A400, there was - a cassette was cheap while the floppies were more than the computer itself!

As to speed, I could load 16KB off my cassette in less than half the time my C64 (yes, I have a couple) could load 8KB from floppy (normal loader). The fast loader did load faster than the Atari cassette, but not by much, and couldn't begin to approach the normal speed of the Atari floppy. It was the ONE biggest complaint I had about the C64.

Edited 2011-07-20 21:34 UTC

Reply Score: 2

RE: Slow?
by Dave_K on Mon 18th Jul 2011 14:01 UTC in reply to "Slow?"
Dave_K Member since:
2005-11-16

I remember running GEOS from a 1541 and being convinced that the drive was faulty. As someone used to the BBC Micro's (relatively) lightning fast drives loading software in a few seconds, I couldn't believe that floppies could be so slow.

At the time the painfully slow drives seemed like the C64's biggest disadvantage as a business computer. It made disk swapping and loading to change between singletasking applications a more frustrating experience, and I can't imagine disks in the 1541 being usable for virtual memory (as they were in some Beeb software).

Reply Score: 3

RE[2]: Slow?
by Zbigniew on Mon 18th Jul 2011 18:11 UTC in reply to "RE: Slow?"
Zbigniew Member since:
2008-08-28

I can't imagine disks in the 1541 being usable for virtual memory (as they were in some Beeb software).

Why not? It depends only on that software - will it use diskette as virtual memory, or not.

Reply Score: 1

RE[3]: Slow?
by Dave_K on Tue 19th Jul 2011 15:13 UTC in reply to "RE[2]: Slow?"
Dave_K Member since:
2005-11-16

Why not? It depends only on that software - will it use diskette as virtual memory, or not.


By "usable" I didn't mean technically possible, I meant practical in real world use.

I remember a BBC DTP app where only the part of the document on screen was stored in memory, and the rest moved to and from virtual memory in real time as it was scrolled through. I doubt that something as fast, efficient and usable as that was could have been achieved with the painfully slow 1541.

Edited 2011-07-19 15:14 UTC

Reply Score: 2

RE[4]: Slow?
by Zbigniew on Wed 20th Jul 2011 13:49 UTC in reply to "RE[3]: Slow?"
Zbigniew Member since:
2008-08-28

[q]I meant practical in real world use. [..] I doubt that something as fast, efficient and usable as that was could have been achieved with the painfully slow 1541.

...but you surely meant original 1541 floppy - without any of available "floppy-speeders". I suppose, that with e.g. JiffyDOS installed (there were even faster ones: Prologic DOS, TurboTrans...) probably it could beat that BBC Acorn floppy.

Reply Score: 1

Very Cool
by transami on Sun 17th Jul 2011 16:31 UTC
transami
Member since:
2006-02-28

You know that is very cool. It's too bad that such a design didn't carry on.

Reply Score: 1

RE: Very Cool
by zima on Sun 17th Jul 2011 20:57 UTC in reply to "Very Cool"
zima Member since:
2005-07-06

More or less quite the contrary? At least some Seagate drives seem to have a real serial port, one to which you could connect with a VT100 dumb terminal (for example to wake up / "unconfuse" seemingly "failed" drive: https://sites.google.com/site/seagatefix/ )

IIRC drive controllers are quite often built around some ARM core now (counting all peripherals, I guess it's not entirely unlikely that a modern PC has, on average, more ARM cores than x86 ones?); then there are firmware updates.

Too bad in too many places the Datasette never really ceased to be a standard... (at least I sometimes had a chance to play with desktop C128 of my cousin) Still not that bad, with fast loaders for Datasette also being a standard.

Edited 2011-07-17 20:59 UTC

Reply Score: 1

Comment by MOS6510
by MOS6510 on Sun 17th Jul 2011 17:00 UTC
MOS6510
Member since:
2011-05-12

I started out using tapes, so floppies were a lot quicker despite them being unnecessarily slow. Things improved with the KCS Power Cartridge fast loader and even more with the Final Cartridge III.

The FC3 needed to be turned off for some games or just stopped working when a game used its own fast loader, like with Ultima 5, which sucked because that game relied on a lot of disk access (and swapping).

The Expert Cartridge allowed you to install a boot loader, a menu and fast loader, you could install on a disk. It would work even with the EC removed.

Reply Score: 2

Painful memories...
by Bill Shooter of Bul on Mon 18th Jul 2011 05:15 UTC
Bill Shooter of Bul
Member since:
2006-07-14

We had a C64, but my father never saw a reason to get a floppy or tape drive. So all of my programs were written on paper, and had to be retyped after each reboot. It was cool at first, but having to re type everything caused me to lose interest after a while and just use it with the game cartridges.

Sort of sucks looking back on all the fun I could have had with the disk drive.

Reply Score: 3

RE: Painful memories...
by Laurence on Mon 18th Jul 2011 12:42 UTC in reply to "Painful memories..."
Laurence Member since:
2007-03-26

We had a C64, but my father never saw a reason to get a floppy or tape drive. So all of my programs were written on paper, and had to be retyped after each reboot. It was cool at first, but having to re type everything caused me to lose interest after a while and just use it with the game cartridges.

Sort of sucks looking back on all the fun I could have had with the disk drive.

A floppy drive I could understand (I started out on an Amstrad CPC646 with no floppy drive), but no cassette drive either!?

That's a little like buying a car and being told the petrol tank is optional.

Reply Score: 3

RE[2]: Painful memories...
by leech on Mon 18th Jul 2011 13:04 UTC in reply to "RE: Painful memories..."
leech Member since:
2006-01-10

I was incredibly happy when my parents one day came home with an Atari 800XL and an Atari 1050 Floppy Drive, we eventually managed to get one of those Happy Chips, now that was awesome!

The Happy Drive changed the beep-beep beep...beep. Into Beeepbeepbeep. Well okay, hard to describe the sounds, but it actually played sound through the monitor as it loaded. I also recall it making some weird farting noises as it'd load up specifically BASIC games.

A friend of mine had a C-64 and it was horrible, even with the fastloader cartridge he had, he'd start loading up a game from floppy, go upstairs, make a sandwich, come back down stairs, and watch a movie, then it'd finally load.

Go figure that due to the 8-bit era, I ended up getting an Atari ST, and he ended up getting an Amiga. Even though the makers of each switched teams and I ended up getting the real descendant of the C64, and he got the one from the Atari 8-bits.

Jay Miner R.I.P.

Reply Score: 2

RE[3]: Painful memories...
by JLF65 on Mon 18th Jul 2011 18:45 UTC in reply to "RE[2]: Painful memories..."
JLF65 Member since:
2005-07-06

I had an Atari 400 with 32KB and a cassette, then got the Percom floppy drive, then a Mosaic 64KB expansion, then the B-Key full stroke keyboard. That served me well for years before I replaced it with an Amiga 500, which served me well for many years again. ;)

Reply Score: 2

RE[2]: Painful memories...
by Bill Shooter of Bul on Mon 18th Jul 2011 14:37 UTC in reply to "RE: Painful memories..."
Bill Shooter of Bul Member since:
2006-07-14

If you had previously spent your life buying horse driven carriages, you wouldn't find the lack of a petrol tank that suspicious on a new fangled horse cart.

Reply Score: 4

RE[3]: Painful memories...
by Laurence on Mon 18th Jul 2011 15:26 UTC in reply to "RE[2]: Painful memories..."
Laurence Member since:
2007-03-26

If you had previously spent your life buying horse driven carriages, you wouldn't find the lack of a petrol tank that suspicious on a new fangled horse cart.

hehehe good point and well put

Reply Score: 2

RE: Painful memories...
by Valhalla on Mon 18th Jul 2011 18:23 UTC in reply to "Painful memories..."
Valhalla Member since:
2006-01-24

We had a C64, but my father never saw a reason to get a floppy or tape drive. So all of my programs were written on paper, and had to be retyped after each reboot.

Heh, awesome. Reminded me of that Monty Python 'Four Yorkshiremen' sketch.

Reply Score: 3

mist64
Member since:
2011-07-19

Dear Thom,

Thanks for linking to the story on my blog.

But please make OSnews.com to what it was supposed to be again, a news site for operating system, platform and low level topics, as it was back in the Eugenia times - not your personal blog, on which you rant about software patents.

Half the topics seem to be about patents, and in stories that don't have anything to do with patents, you still try to find a way to bash patents.

And this story is a very good example. You wrote:

I'm most interested in how he describes others taking his work, and making it better. This would be impossible today, thanks to Microsoft, Apple, and other patent trolls.


Let me fix that for you: This would be impossible today, thanks to copyright law. And it was even illegal back then, it was just that neither the original author nor law enforcement cared enough.

In the F-Copy case, people did not build on top of the ideas of others, but they simply stole the core code and repackaged it.

So please stop bashing patents, leave that to your personal blog.

Michael Steil, www.pagetable.com

Reply Score: 4