Wolfram

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

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)

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.

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.

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.

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

I have already agreed with you that the CIA is useless. you can stop now mr unbiased. Chewbacca defense. You rather argue your out of context point of uselessness. uselessnes was your point. so you're attacking yourself. besides re-read the post I have edited it since then

so... if you cant accept that I'm agreeing with you, I have even agreed that the CIA is useless... so that's not enough, well then let's continue 1. the CIA is not useless. if calling CIA useless is not biased then nothing in this world is. 2. "You wanted to close the topic just by claiming CIA is superior chip when that superiority does not show from software perspective." It was YOUR claim. I have not claimed anything. I have said I agree with YOUR claim. So its not enough when I agree with your claim, because a post later you will find "errors" in your claim, and attack me for agreeing with what you have claimed! its hillarious really! great. lets agree on this, and close this topic. see? its YOUR claim, not mine. I havent claimed anything as you say. Besides CIA's superiority DOES SHOW from software perspective. - 4x 16 bit timers & SID, vs Pokey either doing music or timing. - 2x time of day clock thats clear superiority. live with it. faster system clocks doesnt makes the PIA's better. only I/O. and slower system clock doesnt make's the CIA useless. only from your "perspective".

great. lets agree on this, and close this topic. It does not address the point to have a chip that is superior but loses in I/O transfers and timing. It's useless from software perspective. sure. c64's CIA chips are useless from software perspective. Re-read. Your emotional bias is preventing you from understanding. Use example of FAT AGNUS I gave. I have just repeated what you have said: CIA chips in the c64 are useless from software perspective (because a8 is faster!). its funny how after this you attack me with bias in each of your post

But why would you do IO via joystick ports on C64? You have a full 8 bit parallel port + serial port at the C64 userport available. No need to misuse the joyports. so he can win the argument.

great. lets agree on this, and close this topic. It does not address the point to have a chip that is superior but loses in I/O transfers and timing. It's useless from software perspective. sure. c64's CIA chips are useless from software perspective.

great. lets agree on this, and close this topic.

vice versa. Atari needed MOS for its achievements, and not MOS needed atari.

so its the cpu which is faster, and not the joystick port. the ports are doing the same job. none of them is better. so the atari doesnt uses the PIA timers for anything ? atleast their interrupt lines are soldiered in ? are there timers on those PIA's at all, if the machine uses Pokey timers as you say? CIA can be fed with whatever Mhz, it doesnt makes it a bad chip if its fed with a slower one, and it doesnt makes it a better chip its fed with a faster clock. from the machine's point of view the timers are equally accurate: 1 cycle = 1 tick on both. you need to find an application which needs to measure an outside event at atleast 1.79 Mhz accuracy so that the advantage of this shows.

Crap. Just because it's not living on Flashable EEPROM doesn't mean you don't call it firmware. ok.

atariksi, >Atari has both joystick ports tied to one 8-bit port. Atari even reads nibbles at higher frequency. same as on c64. higher read speed comes from the higher CPU speed, and has nothing to do with the IO chip itself. its just another way telling a8's cpu is faster. it has nothing to do with the "joystick port". >Joystick ports are inferior on C64. Add in the keyboard interference and you are set. its just the same and c64's chip doing the "joyport" offers slightly more. thats all.

?! well if you want to do something with a computer you usually need a peripheral or something.

for god's sake dont quote such a huge post, when all you have to add is really nothing.

As Wolfram said: You mixed up the VIA 6522 in the 1541 with the CIA 6526 in the C64. The C64 serial shift register works fine, C128 uses CIAs for it's faster I/O (1571 has a CIA inside) and it's also used for RS232 transfers. Tramiels had the attitude that he was selling hardware not software. the faulty VIA sat in the 1540 also firmware did not exist back then. and last: C= had its software division, most of the very earliest games were done by them, wisely they helped the machine to launch with software. after 1-2 years it wasnt needed anyway, 3rd party created software like crazy.

you mix things up. the chip with the Serial I/O bug was the VIA and not the CIA. c64 suffered of loading speed because they decided to keep "compatibility" with the vic-20 which had the faulty VIA. conclusion: CIA both better&better implementation, as the PIA is which atariksi claims to have a "better joystick port" edit: after further research it looks like CIA and PIA is pretty much the SAME. the only plus CIA has is a TOD clock, hmm and maybe that CIA timers can count each others underflows.

THERE'S A BIG PIECE OF COMMODORE IN EVERY ATARI ==> the 6502 . the heart of your beloved machine is Commodore! also dont forget about the PIA chips. which are an older revision of the CIA chips. Now the newer CIA chips are used in the c64 for the same purpose, as PIAs in the A8. BUT. atariksi comes and proves, that the older revision PIA has better "joystick" (I/O!) ports than the newer CIAs. the fact is: both chips has 2x8bit parallel I/O ports with programmable direction for each but. another fact is: CIA is a newer revision of PIA thus its better. conclusion: the joystick ports are the same, but c64's chip providing the joystick bort is better.

wrong. so, stop insulting me. I have not attacked you personally either.

You forgot the rest of the characters: Top to bottom: PET, C64 uppercase, C64 lowercase, Atari Top to bottom: PET, C64 uppercase, Atari, C64 lowercase,

What you ask for is impossible because the C64 font is not identical to the A8 font so a generated double pixel width PET font cannot be identical to the A8 font either. Before I originally posted my thoughts and before I even read that article on PETSCII tonight, I had EnvisionPC and the character editor of C64PrgGen up on the screen... The lower case font data between the A8 and C64 are identical... 100% identical... All 26 lower case characters Like I said before... There's a little bit of Atari in every C64... Indeed. looks like commodore copied the a8 font. the pet differs bigger then a simple program could turn it into the c64 font. even stuff like ()[email protected]*;: looks the same.

I read the same article before writing my post Trollfram... Now, if the PET font can be converted to the C64 font with a small program, therefore nullifying what I'm saying... Does that mean the PET font can be redefined as the C64 font? Or the C64 font can be redefined with the PET font? Either or, if case 1 then the PET is redefined with Atari lower case text. If case 2 then the C64 has the PET's lower case which is different than the A8's... SUCKA!!!! "the PET font can be converted to the C64 font with a small program, therefore nullifying what I'm saying..." correct.