Atari v Commodore

[atariksi]

The joysticks were placed okay on Atari 520ST model.

 

No, they were placed 10 different kinds of awful. Many is the time I either tilted the machine up on it's back or hung the front of it off the desk then eyeballed from underneath to get them plugged in. At one point, I had 6ft extensions permanently plugged in just so I wouldn't have to finagle around getting joysticks plugged it. The 520/1040 ST joystick ports easily win the worst-port-placement contest of any machine that I have owned or used.

 

The 520ST that I have has joystick ports in same place as 130XE (on right side). I think there were different models for 520ST so the internal floppy version one may have had the joystick ports on the bottom.

[frogstar_robot]

The 520ST that I have has joystick ports in same place as 130XE (on right side). I think there were different models for 520ST so the internal floppy version one may have had the joystick ports on the bottom.

 

Indeed, I was able to find a picture of one like what you had but was not able to find a picture of mine. My 520 and a 1040 a friend gave me later both had a little niche on the bottom left of the machine underneath the keyboard that the joysticks plugged into. The plugs could only be grasped just above the point the cord enters the plugs. The boxlike niche interfered with any other grip while plugging them in. In addition, the ports were rather tight and pretty hard to shove the plugs into on top of not being able to properly grip them.

[Rybags]

I realised another gripe the other night.

 

You can't plug most aftermarket hobbyist DIY plugs into the joystick sockets on the XEs... PITA.

 

I wanted the 5V source and GND when I was doing the ANx testing with a buffer IC... ended up having to dismantle a set of paddles and using them.

[atariksi]

The 520ST that I have has joystick ports in same place as 130XE (on right side). I think there were different models for 520ST so the internal floppy version one may have had the joystick ports on the bottom.

 

Indeed, I was able to find a picture of one like what you had but was not able to find a picture of mine. My 520 and a 1040 a friend gave me later both had a little niche on the bottom left of the machine underneath the keyboard that the joysticks plugged into. The plugs could only be grasped just above the point the cord enters the plugs. The boxlike niche interfered with any other grip while plugging them in. In addition, the ports were rather tight and pretty hard to shove the plugs into on top of not being able to properly grip them.

 

I think they are called 520STF and 520STFM but it's easier to find 1040STF/STFM on ebay.

[atariksi]

I realised another gripe the other night.

 

You can't plug most aftermarket hobbyist DIY plugs into the joystick sockets on the XEs... PITA.

 

I wanted the 5V source and GND when I was doing the ANx testing with a buffer IC... ended up having to dismantle a set of paddles and using them.

 

Yeah, you need the non-screwable type of cable w/thin end, but I prefer the non-screwable type of cable. Even the MPDOS cable have problems on the XE series but fit in perfectly on XL/400/800. I had to cut some plastic between the two joystick ports to make them fit without having to resort to a Y-cable or extension cable. The Amiga 2000 I have has joystick ports allowing for both-- screwable types and normal joystick cables.

 

I think overall Atari 800 has the best joystick interface-- 4 ports and easily pluggable/removeable. C64 ports are similar to XL for plugging in, but then the keyboard overload and nibble mode instead of byte mode and slower access time make them inferior to XL.

[Rybags]

I'm gonna have to check out this MPDos thing of yours sometime...

 

To have a remote typing (ie from the PC) ability for me would make things so much easier. I have my 130XE sitting on a pissy little 40cm high table on top of the 1050... only place I can fit it ATM.

[malducci]

Musical notes used be the main use in computers since memory was limited but nowadays digitized sample playback is the norm so allowing for 4 DACs to be played at their own rate is better than one DAC (or two at a fixed frequency). Adlib board prior to Sound Blaster did not allow you to adjust volume on each FM channel independently. All the Sound Blasters that I have does not allow you to do it either. So even if you can find some boards that have volume adjustment per channel, once again the point about non-standard useage comes into play. You can't really take advantage of it like you can on Amiga/Atari since you would be making your software specific to a few audio boards.

 

I more familiar with Yamaha's other chips (OPN), but AFAIK all Yamaha chips including the OPL types (even the lesser cut down types with predefined instruments) have an adjustable TL register. There's a pinball game that came out in the early 90's that did the same (or similar) trick that I described to playback digitized samples on FM channels of Adlib sound cards. It wasn't restrictive to a certain set of Adlib cards either.

 

so allowing for 4 DACs to be played at their own rate is better than one DAC (or two at a fixed frequency).

 

Well, that depends on the resolution of the DAC. FM chips accumulate the channel output digitally and then feed it do a DAC. So do some wavetable synth setups. But you're still using a fixed point counter for each channel, right? I assume you're running/incrementing each counter from a timed interrupt. What's the base timer frequency? 15.7khz?

 

And if Malducci thinks I am missing the point, then he's missing a different point than the one that you are missing.

 

Wait... now I'm confused. Hehe.

Edited March 24, 2009 by malducci

[atariksi]

I'm gonna have to check out this MPDos thing of yours sometime...

 

To have a remote typing (ie from the PC) ability for me would make things so much easier. I have my 130XE sitting on a pissy little 40cm high table on top of the 1050... only place I can fit it ATM.

 

I have problem with space as well so I have a few classic machines hooked up to various parallel ports so I can stack them up. Now who was that who mentioned antispace (aspace) and if it were invented, it would be useful. Until then, be my guest to send me an offer for MPDOS Pro through PMail.

[atariksi]

Musical notes used be the main use in computers since memory was limited but nowadays digitized sample playback is the norm so allowing for 4 DACs to be played at their own rate is better than one DAC (or two at a fixed frequency). Adlib board prior to Sound Blaster did not allow you to adjust volume on each FM channel independently. All the Sound Blasters that I have does not allow you to do it either. So even if you can find some boards that have volume adjustment per channel, once again the point about non-standard useage comes into play. You can't really take advantage of it like you can on Amiga/Atari since you would be making your software specific to a few audio boards.

 

I more familiar with Yamaha's other chips (OPN), but AFAIK all Yamaha chips including the OPL types (even the lesser cut down types with predefined instruments) have an adjustable TL register. There's a pinball game that came out in the early 90's that did the same (or similar) trick that I described to playback digitized samples on FM channels of Adlib sound cards. It wasn't restrictive to a certain set of Adlib cards either.

...

There are tricks to make it seem like there are DACs present but that does not count as hardware features. You can easily do a 6-bit DAC simulation using PC speaker beep (1-bit). But the emulated DACs are less accurate and use up CPU power than having a real DAC. Atari ST has a Yamaha chip as well but it has real DACs there which can play any arbitrary sample rather than a musical note.

 

>>so allowing for 4 DACs to be played at their own rate is better than one DAC (or two at a fixed frequency).

 

> Well, that depends on the resolution of the DAC. FM chips accumulate the channel output digitally and then feed it do a DAC. So do some wavetable synth setups. But you're still using a fixed point counter for each channel, right? I assume you're running/incrementing each counter from a timed interrupt. What's the base timer frequency? 15.7khz?

 

Ahm, there are three timers that can be programmed at any frequency you want for interrupts from pretty much 61Hz to beyond 44Khz. The timer base is 15.6999Khz, 63.921Khz, or 1.78979Mhz and then you choose either an 8-bit or 16-bit divisor. You can also use DLI/VCount to play back samples as well. You can also use cycle exact coding to play back samples.

 

>>And if Malducci thinks I am missing the point, then he's missing a different point than the one that you are missing.

 

>Wait... now I'm confused. Hehe.

 

He thought I was comparing Amiga w/Atari audio, but I was comparing with SB cards (and Adlib). You are comparing music being played but not digitized samples. Resolution of DACs makes a difference so Amiga 8-bit DACs are superior to Atari's 4-bit DACs. And a real 4-bit DAC is always superior to a 4-bit emulated DAC using beeps/music notes.

[Fröhn]

He thought I was comparing Amiga w/Atari audio, but I was comparing with SB cards (and Adlib).

I didn't think that and I didn't say that. I only said: A8 audio is not the same as Amiga audio. A8 audio doesn't belong to the same bin as the Amiga audio since you CAN NOT feed the 4 DACs at different frequencies at a reasonable frequency. The only way to get a reasonable frequency needed for sample replay is: Feed all 4 DACs at the same frequency. By doing this, those 4 DACs do the same job as ONE DAC with 2 more bits and software mixing. All the mod-players I have seen do this.

[atariksi]

He thought I was comparing Amiga w/Atari audio, but I was comparing with SB cards (and Adlib).

I didn't think that and I didn't say that. I only said: A8 audio is not the same as Amiga audio. A8 audio doesn't belong to the same bin as the Amiga audio since you CAN NOT feed the 4 DACs at different frequencies at a reasonable frequency. The only way to get a reasonable frequency needed for sample replay is: Feed all 4 DACs at the same frequency. By doing this, those 4 DACs do the same job as ONE DAC with 2 more bits and software mixing. All the mod-players I have seen do this.

 

So you still don't accept you can feed the 4 DACs at different frequencies on the Atari but now you have watered it down to "reasonable" frequency. I gave the example before of 8Khz, 9Khz, 11Khz, and 13Khz which do work. And software mixing is slower and worse than hardware doing the mixing for you without truncation. I am not talking about what I have seen or what you have seen on existing software but what can be done.

[Fröhn]

So you still don't accept you can feed the 4 DACs at different frequencies on the Atari but now you have watered it down to "reasonable" frequency.

I didn't water anything down. If you want to play 4 samples at the same time you simply cannot do it with feeding the DACs at different frequencies. What I meant with "reasonable frequencies" was: "Anything which can be used for sample replay".

 

I gave the example before of 8Khz, 9Khz, 11Khz, and 13Khz which do work.

You only babbled some timer rates down. But it won't work. You will get a lot of DAC-update collisions which the slow 6502 will not be able to handle close to the time they are supposed to handle them, or you wont have enough time at all. As I said: The Halle Project 93 mod player has a 6 kHz busy-loop replayer which updates all 4 DACs interleaved with the same frequency and even that one is pretty much at the limit already.

 

And software mixing is slower and worse than hardware doing the mixing for you without truncation.

Oh yeah really much slower: CLC ADC ADC ADC ADC TAX LDA STA (mixing) vs LDA STA LDA STA LDA STA LDA STA (4 DACs). Both don't truncate.

 

I am not talking about what I have seen or what you have seen on existing software but what can be done.

It can't be done.

[atariksi]

Frohn: It's 16 hours since your latest mistake. I'll give you another 32 minutes to withdraw your mistake or at least think about why you are wrong before I reply.

[atariksi]

So you still don't accept you can feed the 4 DACs at different frequencies on the Atari but now you have watered it down to "reasonable" frequency.

I didn't water anything down. If you want to play 4 samples at the same time you simply cannot do it with feeding the DACs at different frequencies. What I meant with "reasonable frequencies" was: "Anything which can be used for sample replay".

 

I gave the example before of 8Khz, 9Khz, 11Khz, and 13Khz which do work.

You only babbled some timer rates down. But it won't work.

...

 

No babble-- just an arbitrary set of frequencies which I used before in post #2890 which you never replied to. It will work and even for higher frequencies. You shouldn't talk about taking timer rates down since you don't think it's doable at all so all I need to give is one example of frequencies that work.

 

>You will get a lot of DAC-update collisions which the slow 6502 will not be able to handle close to the time they are supposed to handle them, or you wont have enough time at all. As I said: The Halle Project 93 mod player has a 6 kHz busy-loop replayer which updates all 4 DACs interleaved with the same frequency and even that one is pretty much at the limit already.

 

You can't judge by an application what a computer is capable of doing. You have to look at it from a cycle analysis point of view. Collisions is a different subject matter-- you can get a collision even if you play one DAC since there are refresh cycles or DMA cycles (if screen is on). If you play a 9Khz sample on Sound Blaster on a 90Mhz Pentium, you don't get a sample outputting at exactly every 10,000 CPU cycles. You can avoid collisions completely on Atari by selecting certain frequencies and interleaving the cycles.

 

>>And software mixing is slower and worse than hardware doing the mixing for you without truncation.

 

>Oh yeah really much slower: CLC ADC ADC ADC ADC TAX LDA STA (mixing) vs LDA STA LDA STA LDA STA LDA STA (4 DACs). Both don't truncate.

 

You made two mistakes here-- you can't use that instruction sequence for multifrequencies since you have to generate data that's in-between two samples. And secondly, you are mixing up higher bit depth DAC simulation with multifrequency playback-- you playback a 4-bit value that's truncated to the 4-bits before sending to hardware whereas the 4 DACs get merged by hardware to output a 6-bit value.

 

>>I am not talking about what I have seen or what you have seen on existing software but what can be done.

 

>It can't be done.

 

Stick to your position then and don't use chewbacca defense with words like "can't be done at reasonable rate". 8,9,11,13Khz are reasonable rates. I guess you never learned interleaving; here's a simpler example to test a 64Kbytes RAM block where you have to interleave addresses so as to avoid repeats but at the same time not go consecutively-- so you start at arbitrary address 0..65535 and select a prime number > 65536 and keep adding to the address and doing modulo 65536. So let's say you start at 45333 and keep adding 69001, you end up going through all the addresses.

[miker]

This discussion becomes more and more boring. Maybe some *working* examples (or samples ) instead of just theoretizing...

 

(or conclude it - as CharlieChaplin suggested)

[potatohead]

What I don't get is why Amiga audio is even on this thread.

 

Who gives a crap what the Amiga can do? It's a cool machine, but it's not an 8 bit machine, and the thread was about the C64 and Atari 8 BIT MACHINES.

 

The Amiga audio and video timing elements have no place here.

[ThomSW]

100% agreed with miker & potatohead.

 

No examples & lame Amig'ging...

 

Goodnight.

[Godzilla]

yes, maybe some more on-topic comparisons of a8bit games beating pants off the c64? How about 'dimension x' ? did that have a c64 version? the atari version was pretty ace.

[atariksi]

This discussion becomes more and more boring. Maybe some *working* examples (or samples ) instead of just theoretizing...

 

(or conclude it - as CharlieChaplin suggested)

 

Not all algorithms get developed into applications. Sometimes it's interesting to just discuss the good algorithms.

[atariksi]

100% agreed with miker & potatohead.

 

No examples & lame Amig'ging...

 

Goodnight.

 

What's the target machine that you would looking for examples-- currently, my Atari machine is hooked up to PC so I have "unlimited" storage.

[Godzilla]

so have we exhausted the well of games that had superior atari 8 bit versions vs their c64 counterparts? I'd like to see all the comparisons hidden in this thread in one, nice, easy to read place

[miker]

@atariksi:

 

So maybe take advantage of this storage. You have talked about playing samples on Atari at high freq. (not only this, but this one i currently remember) why just don't make some (smaller or bigger) demo illustrating it. Nowadays samples are greatly underestimated on this comp (due to concentrating on "synth" POKEY sound and lack of more "modern" software as well). Maybe its time to fill this niche.

[Rybags]

I was looking to do something like that.

 

Standard SIO speed though is only about 1K per second on a real disk drive... That equates to 2-bit samples running at 4 KHz.

Of course you can have a nice big buffer but eventually you'll get underrun of data vs sample needs.

 

Higher SIO speeds of course could mean half decent quality but in that case you might run into the wall so far as the CPU demand of processing SIO clashing with the playback requirements.

[atariksi]

@atariksi:

 

So maybe take advantage of this storage. You have talked about playing samples on Atari at high freq. (not only this, but this one i currently remember) why just don't make some (smaller or bigger) demo illustrating it. Nowadays samples are greatly underestimated on this comp (due to concentrating on "synth" POKEY sound and lack of more "modern" software as well). Maybe its time to fill this niche.

 

There's SPS (Sound Processing Software) and a multimedia CDROM that's available on my website that works with the Atari and plays back 4-bit and 5-bit samples at upto 21Khz using PC parallel port to Atari joystick port for transmitting samples. Currently, using only two hardware DAC channels and one joystick port but can be modified to use more channels and both joystick ports.

 

RAM drive would be a better option for higher frequency playback of all 4 DACs.

[atariksi]

so have we exhausted the well of games that had superior atari 8 bit versions vs their c64 counterparts? I'd like to see all the comparisons hidden in this thread in one, nice, easy to read place

 

I think you need to ask Allas to post some more game comparisons like he gave one earlier in the thread:

 

ALTERNATE REALITY : THE CITY

 

Atari screenshots

 

Originally programed on Atari systems, Alternate Reality shows how much powerful could be a well programed game on Atari Systems. Is a pleasure to watch a lot of colorful screens, smooth moves and great ambient effects. Despite the C64 have the SID, the Atari music sounds better. This is a extensive game, and Atari have the advantage of his fast disk drive and can use the extra memory to abbreviate the loading. The C64 version is a nightmare to play, because the continue slow loadings.

 

Well, for sure this is a game made-it specially for Atari Systems and C64 lose a lot on the conversion, but really, there are a lot of things on it that can't be reached for a C64. However, the Atari 8bit version could be the best version of all systems including the 16bit

 

C64 screenshots