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Nickolasgaspar

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Everything posted by Nickolasgaspar

  1. To be fair, in the episode 3 he admits he is using a 400/800 cpu board as a blue print. Well he is Dutch so maybe the "reverse engineer" statement is a "language barrier" issue.
  2. Well I don't really understand how you "know it is not". You can literally google the pinout of both versions and find out that Sally just uses two previously disconnected pins (#35,36) to implement a specific function previously performed by 4 logic chips on the main board. Who knows what other changes were made. We weren't members of the "board" during that time to "know" anything. The Default Position in Logic is defined by the available evidence. The things we know about the "Liz" project, their identical pinouts, the ability to reproduce Sally's function by adding some external logic chips, the cost of designing and producing new CPU architecture while there was already a die available and of course the use of the name "6502"...all provide sufficient and necessary evidence to dismiss further unnecessary assumptions.(Parsimony). Maybe there were additional changes...but the moment to accept that claim is only after we can put our fingers on objective evidence. A C014377(400/800 models) is a standard 6502. The pins 35,36 are disconnected and there isn't a logic circuit on the XE mainboard to perform the needed function hence allow a 130xe to function.
  3. How a wiki link on dies is relevant to the modified version of a 6502?
  4. That is not the sense I use the phrase "faster chips". When I say faster, I mean to run faster. Faster chips means more money. That makes no sense in our economic system even back in the 80s.
  5. I think the answer is obvious since the early machines (400 800) came with a standard 6502 and those additional logic chips and the daughter board in this video can run on an XL machine with a standard 6502.
  6. I never said that our posts contradicted each other. In a discussion one can add to other people's comments. I only pointed out that, independent of the method (binning or not) 6502s were graded and Atari's internal nickname (6502C) caused confusion and ambiguity specially when it was included in commercial documentation. There was also no reason to put binned cpus in Atari 8bit and C64 machines because it would affect the rest of their architecture. As far as I know the PCs were the first to allow such upgrades without the need of any daughter boards...and this was their recipe of success.
  7. Check this series of a guy restoring an Atari 800xl . In episode 3,4 and 5 he reverse engineers, designs and builds the circuit that is inside a Sally chip and uses it with a standard 6502. He literally uses 4 logic chips. btw this dude is the high priest of new age woo, Bernardo Kastrup. His philosophy may suck but he is a master in computer engineering.(actually he has a PhD on this).
  8. The 6502C stands probably for "custom 6502". I quote the relative article from atarimania.com "This chip was originally named SALLY by Atari engineers, but Atari Customer Support documents (Field Services Manuals) variously described it as "6502 (Modified)", "6502 Modified", "Custom 6502", or "6502C". Field Service Manuals published by Atari, Corp./Atari Corporation reverted to using the chip's original name, SALLY, while Atari, Corp./Atari Corporation XE consumer owner's manuals (unfortunately) continued to use "6502C" in reference to the SALLY 6502. Several manufacturers produced the SALLY 6502 for Atari, including MOS Technology, Synertek, Rockwell, NCR, and United Microelectronics (UMC). It is important to note that chips marked "6502C" such as the MOS Technology MCS6502C, MOS Technology MPS6502C, Synertek SY6502C, Rockwell R6502C, or UMC UM6502C are NOT the Atari "6502C" but rather equivalents to the standard MCS6502 that are certified for 4MHz operation. Atari SALLY 6502 chips are never marked "6502C" but, other than the UMC UM6502I, always carry the Atari part number C014806." So using letters(A,B,C) to grade 6502 by maximum speed IS a thing but it's not relevant to Atari's C014806 variant. Its only for the standard 6502 cpus. We are talking about two different products. There is another variant that can only be found in early 400, 800 models which appears to be a standard 6502 cpu. The Sally chip replaced a number of logic chips responsible for the same halt routine in those early models. The truth is that Sally chip exists only because of cost reducing practices. link: http://www.atarimania.com/faq-atari-400-800-xl-xe-what-are-sally-antic-ctia-gtia-fgtia-pokey-and-freddie_14.html
  9. I found pictures of the last XE model, the 800XE(its an 65XE in Eastern Europe). They used the 130xe mobo with only two DRAM chips and the ECI port. I have an 65XE with a Freddie Chip and without an ECI port, so I was wondering if there are any XEs versions released without a Freddie chip. It looks like there aren't any. http://oldcomputer.info/pictures/index.php?spgmGal=Museum/8-bit/Atari_800XE&spgmPic=5
  10. I think I found . From what I understand 2 DRAM machines always have an ECI port.
  11. Yes, I happen to have an 800xlf board. So there are variations of the 65XE with 2 DRAMs? Is there a way to tell the difference without opening the machine? Do you have a link to check the board of this version?
  12. Do you know if all 65XEs come with Freddie chips or are there any versions without?
  13. lets compare NTCS vs Pal!!! lol I don't mind the bluish highlights on the NTSC version. It resembles an ambient blue background light.
  14. The SID "metal" always reminded me the 80's porn music. I thought it was my personal bias...until I found out that I am not the only one with that impression.lol
  15. Since my first job was creating digital illustrations I have to say that I do love C64 still images. The higher resolution, the earthy colors and creative use of that grey and purple colors produce real art in my opinion. I really appreciate creative art on limited resources. But again the problem is that there aren't enough colors to produce dramatically different results, without ignoring advantage of the higher resolution in the detail of these images. On the other hand, images on the Atari 8bit line are a bit more "rough" from a resolution perspective but the available hues and colors can produce a huge spectrum of different color schemes. Here is a great image from Lamer's demo "Prozac".(Scrolling picture). If you check this thread you will see many examples of converted still images. Of course they are not "art" but they can roughly show the abilities of the hardware to produce images in a variety of different color schemes. An other great example is the conversion of the "Defender of the Crown" title screen.
  16. This thread's title is about the graphics abilities of two 8 bit micros. I threw in CPC because even coders of that period accepted CPC's superiority over C64's capabilities. (Virgin Software quote in the video below). The homebrew community has proven that all 8bit machines are capable game machines and provided a larger pool of "data" for our evaluations. Some are better in specific genres than others. Sure, scrolling looks great on C64 and Atari machines with their dedicated hardware, Pseudo 3d and scaling is superior on atari 8bit computers due to Miner's advanced architecture(I saw a new C64 racing game with impressive scaling), and "16bit" like appearance is CPC's strong point without having many serious drawbacks in scrolling or sound. In my opinion and based on old and new game library , the Atari 8bit line and the CPC are the most balanced machines since they both score really high in all categories (graphics/colors,scrolling/scaling,sound). Of course we are forgetting MSX2 machines with their objectively superior graphics and Speccy's aesthetic which is so unique and artistic in so many instances. I would be equally happy owning any of the 8bit classics micros but I have to admit though, in the case of the C64, its the support this machine enjoyed during his commercial life not its graphics that would justify my satisfaction. Well I don't really play games anymore(I just test them for some secs) so my critique is solely based on my initial impressions on their graphics, sound and control response.
  17. Can't really disagree with anything you said. I would also agree with your main criterion. "It has to make the fewest concessions with nearly every game type. " I didn't own an Amstrad in my childhood and my opinion is based on how capable the machine looks in Home brew projects. It appears that the Z80 is powerful enough to scroll things around on its own. It is true that C64 games(as I already wrote) reached the limits of the machine during his commercial life...earlier than any other 8bit. Its also true that the Atari's custom chips/architecture were far more advanced and the Z80 is a superior cpu in many ways for the programmers to take full advantage of them(Atari's "embargo" on third party software did really help lol). This is why we never managed to see in full the limits of those machines. Complex hardware and the invasion of 16bit machines in 1985 made things even more difficult. Now even the Speccy has amazing " tech demos" of games producing more inviting end result(graphically) that the good old C64, in limited cased of course). Sure the fluidity in animation by a dedicated hardware can not be matched by those two British machines , but our brains also need color and graph to be trick in the "story". So I guess its all about how ready you are to accept reduced colors and graphics or reduced quality in animation. This is why I believe the Atari 8bit line holds a sweet spot. Many colors, great animation.(and I know that there is some bias in there).
  18. Here is how this picture is supposed to look ( PAL version/all lines). Now the homebrew community has shown that Jay Miner's machine has a superior architecture, rendering the specs you mentioned,in my opinion, almost irrelevant(its an IPC issue). Sure C64 sprites logic is superior since it was newer by some years, but even with that deficit the Atari machine manages to outperform it by using many of its tricks. Software sprites are easily animated by its faster architecture and CPU clock(Albert,RGB, project Abyssus, The extirpator, Calisto,Pang etc)the hardware scrolling and scaling capabilities have allowed games (Yoomp!, Space Harrier,Total Eclipse, Stunt car racer) to appear colorful , display a larger screen and provide higher frame rate. The machine's lower resolution does help of course but at least atari games don't all look the same (C64 Dirty grey look). The POKEY chip can simulate SID's tone and ever produce clearer sound while doing it...but I can understand that sound choice is based on our subjective preference. The fact is that SID can not reproduce POKEY's SFX and dynamic music sounds while the POKEY can't reproduce SID's bass. The C64 was designed to be sold in SM and toy stores so for its price tag the machine was surprisingly good, but we managed to see almost 100% of its capabilities during its commercial life. The Atari 8bit line still surprises us with what the home brew community is delivering. They are both good machines...but I find Miner's work to be superior and for my second choice (if not the first) it will always be the "scrolless" Amstrad 6128 with its limited but amazing color palette, ideal for arcade games and decent sound chip. I just love what I see on the CPC! Even the programmers of the contemporary software houses admitted that they felt writing code for a superior machine when they were working on the CPC. So my classification for the 8bit multimedia micros group is 1.Atari/CPC 2. C64
  19. Here is an Atari 1200XL running C64 Basic & Kernel! The benchmark results are really interesting!
  20. lol....I think you will need a PC for this one.
  21. Enjoy this rare alliance between these two sound chips rivals. ( you can find more Pokey-Sid Music Mix in this channel).
  22. I did the same thing on the PoP thread and now...revived the conversation and now its a bloodbath lol. Fortunately the users here understand that an opinion on this question is subjective and can be affected by practicality of both choices. It is also fair to say that it is reasonable to expect from most people in a forum on retro computers to have access to real hardware and emulation!
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