Atari v Commodore

[atariksi]

The *superiority* of the CIA chip over PIA is useless from software perspective.

 

2x 16 bit timers with various modes & interrupt triggering, and a Time of Day clock is not useless from software perspective.

 

Let's first agree joystick I/O is superior on Atari then we can talk 2*16 timers...

[Wolfram]

which used to require a modded "Happy" floppy drive, but which the feature-laden, affordably priced $50 SIO2PC happily supports

 

you are comparing a modded a8 drive, and pc-a8 connection to an unmodded 1541's transfer speed. an unmodded 1541 with uploading software into it can beat the a8 in disk loading speed.

[Wolfram]

The *superiority* of the CIA chip over PIA is useless from software perspective.

 

2x 16 bit timers with various modes & interrupt triggering, and a Time of Day clock is not useless from software perspective.

 

Let's first agree joystick I/O is superior on Atari then we can talk 2*16 timers...

 

 

I only agree if you wont come back and attack me for agreeing with you, as the last time.

[potatohead]

@Bryan: Thanks for the clarifications!

 

I understand what you are saying. Thanks for picking through a monster post. I really find this stuff interesting and fun!

 

I was really expanding on the hack that Woz did, and it's quite useful. All that is needed for that high resolution pattern to display a color is a correctly generated color burst in the HSYNC. If that burst has a consistent phase, artifacting will result in colors. The actual color seen, disregarding the tint variation seen on displays, depends on the relationship between that burst and the pixel. There was a PC add on card in the late 80's that did exactly that. It had a 2400 pixel display, with a few lumas per pixel. It did thousands of colors, via the exact method I described.

 

Easy way is to just consider each color clock, one pixel, then sub pixels in there go around the color wheel. That works every time. The beauty of it then is very simple math, in multiples of the color burst tells all. Easy to write code then. Use alternating phase and you get 320 pixel resolution, with displays able to resolve any pixel fairly well.

 

Noise does not appear to manifest on many displays these days. If you over drive it, older TV's will buzz, but only when poorly tuned. (I've checked this out on a ton of displays.) Worst case is the pixel ends up with a bit of texture. No worries for computer graphics.

 

The Atari "pixels" seen in the luma space really are mostly the peak of the sine wave it outputs. That peak is seen as a luma pixel, about 1/3 the size of a 320 mode high-res pixel. Most capture cards, running in S-video mode will round that to a nice, square pixel. Thank you for that bit of info, BTW. It explains part of why the 640 mode hack I did as a kid worked on good, analog monochrome displays and not so well on capture cards today. Seeing only the peak of the sine means a nice, small luma foot print, and those can be interleaved for more resolution on the A8. I've got to get a monochrome display now... so I can finish that up some day and post up a picture.

 

That also means I get to take back how Atari 8 bit does color. It's not really the artifacting, pixel method. However, using that method does produce the A8 palette very closely. That's what I did with the Prop as a first project. Do Atari style fixed chroma video. That led to the various artifacting bits of fun I've tried with various machines. The CoCo deal was really revisiting something I did way back when to get more colors. At that time, I just knew the machine would put 8 bits of data in one color clock, so exercising that would generate a lot of colors. (it did, nearly 256)

 

Thank you also for confirming the C64 color phase bit. IMHO, given how most computers were doing color in the 80's (fixed phase), I thought it a nice move then, and still do. On a good display device, that means clear, colored 40 column text. A C64 strength. Considering that is one of the good parts about the machine, one wonders why it was such a topic...

 

The Propeller is a video playground. Been learning a lot on the thing. Software video is where it's at, IMHO. That chip can emulate the output of most of the machines we like. Only weak point is luma. I'll have to build a DAC and fix that someday. For a full on, quality implementation of NTSC color, see what Eric Ball has done. Very nice output from the chip. I'll be toying with that for quite some time.

 

 

 

Back on C64: Hmmm... looks like the high speed SIO is useful after all. Hat tip to Atari on that one still!

[+wood_jl]

which used to require a modded "Happy" floppy drive, but which the feature-laden, affordably priced $50 SIO2PC happily supports

 

you are comparing a modded a8 drive, and pc-a8 connection to an unmodded 1541's transfer speed. an unmodded 1541 with uploading software into it can beat the a8 in disk loading speed.

 

Yeah, sure. "BECAUSE YOU SAY SO", right? I've provided numbers and links as evidence. You just say it can beat a8 in disc loading speed. Proof? Numbers? Links? The slowest/shittiest disc system in the world is faster than a8 because YOU SAY SO. BWAH HA HA HA HA!!

 

Let's compare pc-a8 connection to pc-C64 connection, then, since it's a $50 (or $30 for RS232) connection on the Atari. Are you going to get that little round serial port on the back of the C64 to hit 57,600 bps?

 

This is typical. When biased Commodore users start arguing, turn to the subject of 1541 and you'll get some creative bullshit, to be sure. What you WON'T get is evidence and numbers to back up their claims, because there AREN'T ANY. What you'll get is the above quoted BS, and then a call to quickly change the subject to one of the C64's strengths.

 

It used to be like Commie repellant to bring this up; they'd run. Now it's like dogshit attracting flies - they don't leave but bullshit incessantly instead, with no proof, mind you.

 

Prove my point, Wolfram: Are there **ANY** weaknesses **AT ALL** to the C64, or is it simply God's Absolute Perfection in 8-bit form? Even the slowest/shittiest disc system the world has ever known suddenly becomes the best the world has ever known. Which one of the angels is responsible for that disc system?

Edited April 18, 2009 by wood_jl

[Wolfram]

Atari's default "slow" 19,200bps/1024 (1K) = 18.75 kB/sec.

"Warp Speed" 57,600bps/1024 (1K) = 56.25 kB/sec. SIO Max. SIO not "slow" compared to Commie.

 

Plain CBM loader: 0.39 kB/s

Final Cartridge 3 (multifunction cart from 1987): 3.85 kB/s

Action Replay 6 (multifunction cart from 1989): 5.88 kB/s

Warpcopy (disk image transfer tool reading disk from real 1541): 22.09 seconds for a 174848 bytes disk image -> 7.73 kB/s

 

 

the question is wether your examples are presenting the speed without accounting for the job the disk drive has to do.

 

the c64 numbers are true disk loading speeds.

the a8 numbers I'm afraid are pure wire troughput speeds.

[Bryan]

Last time I checked, 300 bytes per second X (8 bits/1 byte) = 2400 bits per second. Does that math confirm with you?

 

Likewise, 4kB per second is NOT 10kB per second. Agreed?

 

Atari's default "slow" 19,200bps/1024 (1K) = 18.75 kB/sec.

"Warp Speed" 57,600bps/1024 (1K) = 56.25 kB/sec. SIO Max. SIO not "slow" compared to Commie.

 

Serial transmission is usually 10 bits per character since there's a start and stop bit to keep it all aligned.

 

In most cases, 19200bps = 1920 bytes per second.

[Bryan]

@Bryan: Thanks for the clarifications!

 

I understand what you are saying. Thanks for picking through a monster post. I really find this stuff interesting and fun!

 

you're welcome.

 

Thank you also for confirming the C64 color phase bit. IMHO, given how most computers were doing color in the 80's (fixed phase), I thought it a nice move then, and still do. On a good display device, that means clear, colored 40 column text. A C64 strength. Considering that is one of the good parts about the machine, one wonders why it was such a topic...

 

The C64's video is one step closer to real NTSC than the A8's and I'd imagine that it does help the clarity of the 320 mode.

 

The Propeller is a video playground. Been learning a lot on the thing. Software video is where it's at, IMHO. That chip can emulate the output of most of the machines we like. Only weak point is luma. I'll have to build a DAC and fix that someday. For a full on, quality implementation of NTSC color, see what Eric Ball has done. Very nice output from the chip. I'll be toying with that for quite some time.

 

Cool. I'll have to check it out.

 

-Bry

[Bryan]

Question: can the 64 set its joystick pins to output? (sorry, I scanned back and couldn't find if that had been answered).

[Wolfram]

Last time I checked, 300 bytes per second X (8 bits/1 byte) = 2400 bits per second. Does that math confirm with you?

 

Likewise, 4kB per second is NOT 10kB per second. Agreed?

 

Atari's default "slow" 19,200bps/1024 (1K) = 18.75 kB/sec.

"Warp Speed" 57,600bps/1024 (1K) = 56.25 kB/sec. SIO Max. SIO not "slow" compared to Commie.

 

Serial transmission is usually 10 bits per character since there's a start and stop bit to keep it all aligned.

 

In most cases, 19200bps = 1920 bytes per second.

 

if thats correct, it brings out c64 with software speeders being faster.

 

~5760 bytes / sec (needs HW mod iirc)

 

vs

 

5,88 kb / sec (needs software upload, but HW wise its still the slowest/shittiest disc drive in the world)

[atariksi]

... besides re-read the post I have edited it since then

 

I don't know which post you edited as there are many that you edited. And it's not a good practice to edit your post after they have already been replied to (or read). I think it's called tampering...

[Wolfram]

Question: can the 64 set its joystick pins to output? (sorry, I scanned back and couldn't find if that had been answered).

 

on one CIA both I/O ports are used up for joystick/keyboard/paddles, output is used to scan the keyboard.

on the other CIA one I/O port is used up for serial I/O, RS232, etc.

 

only one port appears to be free for whatever.

 

its pretty messed up they tried to cram as much stuff as possible into those ports. (joy/keyb/paddles/rs232/serial io/vic banking)

 

http://unusedino.de/ec64/technical/aay/c64/ciamain.htm

Edited April 18, 2009 by Wolfram

[potatohead]

It's hard to see the 1541 as an advantage!

 

Sure, it can compute some things. Nice trick. That's making use of a kludge really. Cool and all of that, but not really a value add.

 

Hey, why not just add a graphics system to the 1541?

 

http://www.propgfx.co.uk/

 

That thing is about to be released and features a serial interface. Perfect for those 1541's! They can run demos, right off the disk! Develop on the C64, insert disk, connect graphics and watch it go!

 

Fun aside, they are big, slow and don't really add a lot of value. The interface to them sucked. The OS support sucked too.

 

This is not a strength of the C64. Come on man!

 

..or is it still, "SAY IT!"... ?

Edited April 18, 2009 by potatohead

[Bryan]

if thats correct, it brings out c64 with software speeders being faster.

 

~5760 bytes / sec (needs HW mod iirc)

 

vs

 

5,88 kb / sec (needs software upload, but HW wise its still the slowest/shittiest disc drive in the world)

 

The 1541 is certainly a more capable piece of hardware than a 1050. Atari only put enough RAM in their drives to buffer a sector and keep a few variables for the ROM-based firmware. Of course there were plug-in hardware upgrades for the Atari drives, and there were speed-up cartridges you could buy for the 64. There were also enhanced 3rd party drives for the Atari. I never knew anyone that had a 3rd party C64 drive, though I saw them in magazines.

 

Anyway, the 1541's problem was its FUBAR firmware which was nightmare for the kids with 64's back in 83-84. Once the speed-ups started becoming more commonplace, it wasn't so bad.

Edited April 18, 2009 by Bryan

[Wolfram]

It's hard to see the 1541 as an advantage!

 

Sure, it can compute some things. Nice trick. That's making use of a kludge really. Cool and all of that, but not really a value add.

 

Hey, why not just add a graphics system to the 1541?

 

http://www.propgfx.co.uk/

 

That thing is about to be released and features a serial interface. Perfect for those 1541's! They can run demos, right off the disk! Develop on the C64, insert disk, connect graphics and watch it go!

 

Fun aside, they are big, slow and don't really add a lot of value. The interface to them sucked. The OS support sucked too.

 

This is not a strength of the C64. Come on man!

 

..or is it still, "SAY IT!"... ?

 

let me answer by qouting one of your collegaues

 

"Yeah, sure. "BECAUSE YOU SAY SO", right? I've provided numbers and links as evidence. ... Proof? Numbers? Links? ... BWAH HA HA HA HA!!"

 

"What you WON'T get is evidence and numbers to back up their claims, because there AREN'T ANY. What you'll get is the above quoted BS, and then a call to quickly change the subject"

 

"it's like dogshit attracting flies - they don't leave but bullshit incessantly instead, with no proof, mind you."

 

"Prove my point, ... Are there **ANY** weaknesses **AT ALL** ... or is it simply God's Absolute Perfection in 8-bit form?"

 

[Wolfram]

if thats correct, it brings out c64 with software speeders being faster.

 

~5760 bytes / sec (needs HW mod iirc)

 

vs

 

5,88 kb / sec (needs software upload, but HW wise its still the slowest/shittiest disc drive in the world)

 

The 1541 is certainly a more capable piece of hardware than a 1050. Atari only put enough RAM in their drives to buffer a sector and keep a few variables for the ROM-based firmware. Of course there were plug-in hardware upgrades for the Atari drives, and there were speed-up cartridges you could buy for the 64. There were also enhanced 3rd party drives for the Atari. I never knew anyone that had a 3rd party C64 drive, though I saw them in magazines.

 

Anyway, the 1541's problem was its FUBAR firmware which was nightmare for the kids with 64's back in 83-85. Once the speed-ups started becoming more commonplace, it wasn't so bad.

 

nah, IF you didnt know the a8, typing in some commands was perfectly fine, and userfriendly, you just didnt knew it could be easyer I'm much more angry for the decision to keep compatiblity with vic20, which resulted in a 8-10x slower then possible loading speed. (HW bit banging vs SOFT bit banging) soft bit bang loaders managed to crank up the speed by 16x, so I assume even a lousy factory programmad HW bit banger would have been like 10x faster.

[atariksi]

So they used some tricks with special loaders (etc) to speed it up. Guess what? That doesn't make it fast.

 

guess what it's faster than a8 ever will be. it was faster when it mattered. and now when it doesnt matters anymore you take the advantage which made it faster and turn the tables and make it a disadvantage. very creative arguing I have to admit.

 

"faster than a8 ever will be" reflects some emotional sentiment rather than fact. You really need to prove this if it's not just another biased conjecture.

[FastRobPlus]

It's hard to see the 1541 as an advantage!

 

 

Fun aside, they are big, slow and don't really add a lot of value. The interface to them sucked. The OS support sucked too.

 

You forgot to add that they don't do what I feel is still their primary function - load games.

 

If I were to go to a retro game con or swap meet, I'd be fine bringing one 1050 along to load/test games. If I were doing C64 disk testing, I'd want to take 2 or 3 tested and working drives because they all knock heads and read differently.

This is what I hate about the SX-64. You can't take it to shows to test media cause the internal drive won't keep alignment under heavy use.

[Wolfram]

So they used some tricks with special loaders (etc) to speed it up. Guess what? That doesn't make it fast.

 

guess what it's faster than a8 ever will be. it was faster when it mattered. and now when it doesnt matters anymore you take the advantage which made it faster and turn the tables and make it a disadvantage. very creative arguing I have to admit.

 

"faster than a8 ever will be" reflects some emotional sentiment rather than fact. You really need to prove this if it's not just another biased conjecture.

 

proof is a few posts above. HW modified a8 drive is slower then 1541 with a software speeder.

[Fröhn]

Atari's default "slow" 19,200bps/1024 (1K) = 18.75 kB/sec.

"Warp Speed" 57,600bps/1024 (1K) = 56.25 kB/sec. SIO Max. SIO not "slow" compared to Commie.

bps is "bits per second". Since there is also start and stop bits, a byte needs 10 bits.

 

19200 bps = 1.875 kB/sec

57600 bps = 5.625 kB/sec

 

Now that's bus transfer only! No disk access counted.

 

The numbers I measured INCLUDE disk access, they are from actual loading times and not theoretic bus transfer speeds.

 

Let's repeat the post I did earlier this day:

 

That's pure bus speeds which are pretty much academic. Let's do a real world test.

 

For this test I took an empty disk, wrote a 50k file (51200 bytes) to it and loaded it with different loaders. Before loading the directory was loaded so the drive head was on the directory track.

 

Plain CBM loader: 128 seconds (0.39 kB/s)

Final Cartridge 3 (multifunction cart from 1987): 13 seconds (3.85 kB/s)

Action Replay 6 (multifunction cart from 1989): 8.5 seconds (5.88 kB/s)

 

EDIT: Another test with Warpcopy (disk image transfer tool reading disk from real 1541): 22.09 seconds for a 174848 bytes disk image -> 7.73 kB/s

 

I hope you agree that 5.625 kB/sec < 5.88 kB/sec, especially if you consider that those 5.88 kB/s INCLUDE disk access which basically means the actual bus transfer speed is 3 times faster than that, the rest of the time is wasted on reading sectors from disk.

[Wolfram]

It's hard to see the 1541 as an advantage!

 

 

Fun aside, they are big, slow and don't really add a lot of value. The interface to them sucked. The OS support sucked too.

 

You forgot to add that they don't do what I feel is still their primary function - load games.

 

If I were to go to a retro game con or swap meet, I'd be fine bringing one 1050 along to load/test games. If I were doing C64 disk testing, I'd want to take 2 or 3 tested and working drives because they all knock heads and read differently.

This is what I hate about the SX-64. You can't take it to shows to test media cause the internal drive won't keep alignment under heavy use.

 

never had an sx64, maybe its drive is outstandingly shitty, but bear you. I have been on oncounted numbers of such a parties, and never encountered such problems. Once with a friend we have mistakenly swapped drives, and had no problems with the other one. In fact never ever would think, I should have problems with it. Swapped games with like 50 ppl in the heyday, I have never met such a problem that a disk works on one drive but doesnt on another one.

 

Did you know that in the 80's there were so called "swappers" on the c64 scene, who did nothing but snailmail out newly cracked games to their "contacts" get back new one etc etc. Many guys posted/got each day a few disks. And the problem you adress somehow just didnt occured. They could swap hundreds and thousands of disks, some guys had like 100 "contacts". that means 100 different drives. and guess what. swapping worked without aligning drives all day long.

 

the swapping "scene" refutes this claim heavily.

[Bryan]

nah, IF you didnt know the a8, typing in some commands was perfectly fine, and userfriendly, you just didnt knew it could be easyer I'm much more angry for the decision to keep compatiblity with vic20, which resulted in a 8-10x slower then possible loading speed. (HW bit banging vs SOFT bit banging) soft bit bang loaders managed to crank up the speed by 16x, so I assume even a lousy factory programmad HW bit banger would have been like 10x faster.

That's what I was referring to, the speed. When a couple friends of mine got 64's they'd put in a disk, start the load, and then go do something else. Occasionally, they'd pop the door open to see if the drive reacted or if the whole thing had locked up. I was envious of some of the 64's games, but that drive was such a turn-off. I'm glad for 64 users that it turned out to be fixable through software.

 

The A8 wasn't a speed demon, but most things loaded in under 30 seconds.

[carmel_andrews]

Actually, the 6502 was sold/marketed before commodore bought MOS

 

CBM bought MOS so as to not relying on an external supply of semiconductors, like ATARI did

 

And as I recall MOS got the big break when ATARI chose them to supply the processor for the VCS

Edited April 18, 2009 by carmel_andrews

[atariksi]

So they used some tricks with special loaders (etc) to speed it up. Guess what? That doesn't make it fast.

 

guess what it's faster than a8 ever will be. it was faster when it mattered. and now when it doesnt matters anymore you take the advantage which made it faster and turn the tables and make it a disadvantage. very creative arguing I have to admit.

 

"faster than a8 ever will be" reflects some emotional sentiment rather than fact. You really need to prove this if it's not just another biased conjecture.

 

proof is a few posts above. HW modified a8 drive is slower then 1541 with a software speeder.

 

Mr wood_jl was talking about drive simulators as well so the OS boot/sio rate/and drive all were taking into consideration. SIO rate > 300,000 bps and is doable in a software simulation. I have done 357,000bps myself with a slow parallel port.

 

Regardless, when you make some absolute claim like "faster than a8 ever will be" that means using any means.

[Wolfram]

Actually, the 6502 was sold/marketed before commodore bought MOS

 

CBM bought MOS so as to not relying on an external supply of semiconductors, like ATARI did

 

And as I recall MOS got the big break when ATARI chose them to supply the processor for the VCS

 

 

Commodore could only buy MOS because MOS was almost broke.

 

- C= PET came out in 1977, and PET happened after C= bought MOS

- 2600 came out in 1977