$d400 inline changes - inspired by $d011 triggering... ;)

[$d400 inline changes - inspired by $d011 triggering... ;)]

Now at some point I have managed to kill these RAMS, they were replaced. From that point I kept loosing RAM contents with lowest refresh rate.

 

Back in the 80s, one of the Atari magazines, Antic I think it was, ran a gag article called PaperWeight with type in program. This program purported to trigger a "self-destruct" register that Atari had supposedly embedded should they need to dispose of some A8s ET-style. All it did was throw up an "April Fool!" type gag.

 

This suggests a way to do it for real .

[10 signs of a fanboy]

What's the difference between a fanboy and a fanboi?

 

Fanboi is even more live-in-your-parents-basementy. It sounds vaguely French which is what I suppose gives it that extra touch of effeteness.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Yeah, it has two 8520 chips-- for floppy controller, keyboard, serial port, LED lights, etc. I had to interface to it when making the floppy simulator as pictured here: http://www.mpdos.com.

 

Aren't those somewhat notorious for blowing out?

[Atari Vs C64 --- 80s Computer scene etc chat...]

Fact is that I know how to obtain the features I talked about. If I'd have the time, my task would be to write a doc about '"how to make full use of Pokey's features".

 

If it is your intent to convince others then you'll need to come across with examples. Nobody has to believe anything. Since you are the one making positive assertions then demonstrate them. You said bare examples of the effects can be realized in BASIC? Then post them!

[Atari Vs C64 --- 80s Computer scene etc chat...]

people have to learn any "music" its not like when you get born, you come out equipped with liking guiter piano and whatever sounds

 

I believe the point he was trying to get at is that chip music is an acquired taste and most non-geeks aren't going to want to listen to much of it. Take something like Switched On Bach, a geek will appreciate what Wendy Carlos got out the electronic music equivalent of a stone ax. Most people will just hear beeps and boops that sound something like high school music class.

 

Past a certain point, I feel the same way myself. Early seventies synths did best accompanied by guitars, drums, and so forth. Except for few Kraftwerk type acts, they weren't the entire show. The SID was an amazingly capable thing to find in an early eighties home computer and better in most ways than what Carlos made that album with. The appetite for pure SID (or POKEY for that matter) chiptunes outside our little geek universe is limited at best.

[ACE80-XL?]

First, using WORD for the logo had some definite limitations. Second, when I tried to use Photo/Paint programs, the text lettering was pretty ugly. Ultimately, WORD seemed the better choice.

 

 

-Larry

 

You may do better with either a vector editor or a true DTP program. Inkscape is a decent free vector editor. It can even do a decent job of importing PDFs and then letting you edit the text. Pretty slick, that.

 

Scribus is a freebie Desktop Publishing package.

 

Either will let you create a graphical label without jagging up the text or doing something horrible to the graphics.

[Atari Vs C64 --- 80s Computer scene etc chat...]

I dunno.. I had a 1040ST, MegaSTE & Falcon030 in my quest to radically support Atari. Today I think they're all crap compared to the Amiga and I've never personally owned one.

 

-Bry

 

Agreed. I went from A8 to ST and was later exposed to some friends Amiga's in the early 90s. I thought the OS, games, and the whole package in general was *incredible*. For the sake of fairness, I've never seen a Falcon but from what I've read they played catchup to A500s at best.

 

Sure, I saw a few "guru meditations" but that business of sliding screens around was slick and there was something bad wrong with who ever came up with "Orc Attack". That was good sick fun.

[Atari Vs C64 --- 80s Computer scene etc chat...]

agreed, some people will never admit that c64 is better in gfx and sound and games in general. see my post above.

 

I attempting to be tasteful but it's real tossup between you and emkay who the king of the 15 year olds are. Do you truly expect to argue everyone in an A8 forum into falling prostrate at the alter of the grand and glorious C64? For crying out loud, have you eschewed food and sleep just to rebut everyone on the net that liked their Ataris better?

 

I'm interested in the history and workings of the machines I dug when I was a kid and will accept correction if I get something wrong but care little which is "better". Though I do find Miner style "scanline generator" chipsets neat and no C64s don't generate video the same way an A8 does (You're quite welcome to like the other way better). And yes the C64 architecture is a bit more flexible in terms of clocking it's components. Yeah there's some challenges doing it for a C64 but a 20Mhz "superCPU" is more difficult for an A8. Again, I'm making no claim of superiority. I just find A8s and Amigas elegant from an engineering point of view. You'll just have to forgive if I'm still able to look back on them fondly in spite of your tactless trashing.

[Atari Vs C64 --- 80s Computer scene etc chat...]

The 128 was a sad story in a way, didn't stand a chance being priced so close to the Amiga.

 

 

Besides a relic compared to the 16 bitters coming, the C128 was subject to the same market disease higher memory models of the A8 suffered from. Any A8 could be counted on to have 16K while others could have anywhere from 24K to 128K (factory..I'm not counting 3rd party mods and their differing banking schemes). So many games especially the ports that are sparking so much frisson in this thread would go for the 16K target. In the same vein, why develop for the C128's capabilities when the installed base of C64s was so much larger? A few houses like Hewson made games that were enhanced on the C128 but well playable on the C64 but most didn't even bother.

 

It took a awhile for this lesson to sink in. I think this also why enhancements to game consoles generally don't fly unless sold WITH the game.

[Atari Vs C64 --- 80s Computer scene etc chat...]

You know we can argue which is better forever on here. I know the C128 had a 2mhz cpu, but could only be used in C128 mode.

 

Agreed. You'd think some people never mentally got past the age of 15. "My 30 year old computer is better than your 30 year computer!"

 

"Uh uh!"

"Uh huh!"

 

....

 

Let's get real here. Any computer made after 1990 or so will spank both the A8 and the C-64 in every respect. By the time you can emulate either one with reasonable accuracy......

 

Incidentally, it is possible to get the 2Mhz speed in C-64 mode. This also goes back to what a said several pages ago about the C-64 design being more modular. Everything in an A8 or any Jay Miner style architecture is based around even multiples of the vertical video refresh. This makes reclocking an A8 take a bit a more circuitry and you'll still have to operate at an integer multiple of the master clock. This is a tradeoff because that's also what makes the A8 "tricks" possible.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Sid is not much better than Pokey, just listen to 'The Big Demo'. Anyway, Pokey's were used in numerous arcade machines.

 

True but arcade machines typically had the advantage of using two to four of them. Also, arcade machines had more cycles to spare for diddling the registers in those POKEYs. Yeah, the A8 can reproduce those sounds but it may not be able to do it and animate a game at the same time. I've also read some threads where some people are experimenting with clocking the POKEY at different rates. Did any arcade games ever manipulate the clock rate of it's POKEY's?

[Atari Vs C64 --- 80s Computer scene etc chat...]

APE is simpler for what I know (not much) . Coding anything thats fast and drive related on the c64 is a timing HELL. as the bit shifting mechanism from the CIAs is missing you have to handshake before each damned bit. and you have to do it fast, and time it correctly. as the c64 is slightly slower than 1 mhz and the 1541 is exactly 1mhz you can not also just sync once. the best you can get is only handshaking for each byte, but in that scenario you have to avoid all extra VICII DMA which stops the cpu (sprites&socalled badlines)

 

Maybe so but I was talking about interfacing a 1541 to a PC through the PC's parallel port. So it may indeed be problematic as you say but even an old slow PC can bit bash a parallel port faster than that. So the PC author does have the job of implementing a serial protocol but then he had that job already. What's more, you are likely only interfacing that drive to create disk images. So while fast is nice, you don't have to beat your brains out for it because any given disk need only be read once.

 

On the other hand a 1050 can be plugged into a PC serial port with a fairly simple adaptor. So the PC author doesn't have to do much in the way of writing a low level serial protocol but he does have to talk to the drive with low level SIO commands because with Atari drives most of the smarts were in the computer rather than the drive.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Do the 1541, 1571 boot up or does one always have to write the LOAD "*',8,1 or something similar? I'm not trying to find fault-- just for comparison as I have an atari behind my PC and never touch it-- just power it on and the PC controls the disks/keyboard/joystick/etc. but that requires that it boot directly into my application. I'd be interested in the smallest possible boot sector that I can transmit to a C64 so I can control it from a PC.

 

The 1541 is pretty much a self-contained computer. It "boots" from ROM pretty much instantly. For the most part, a C-64 doesn't have anything comparable to the DOSes we run on A8s because the computer need only issue instructions to the drive and just have a few simple routines to receive what comes from the drive. Assuming you somehow account for the non-RS232 protocol, those commands can issued from something that isn't even a C64. Software like "Star Commander" can be a lot simpler than software like APE because of the smarts in the drive.

 

You typed commands like LOAD "*",8,1 because the DOS built into the 1541/1571 isn't menu driven.

 

Granted, there is some serial handling code that by default sucks but that is addressable with fastloaders.

[Atari Vs C64 --- 80s Computer scene etc chat...]

I seems a moot point to argue the point which was "better" in graphics, considering how primative both machines are by today's standards; any non-8-bit enthusiast spoiled on modern hardware would find the primitive displays of both machines suck equally. In reality, they both played a great game.

 

Agreed but it is fun to pick over the fun points as long as nobody takes anything personally. It is a geek affliction to see his technological choices as evidence of his good taste. I think that fuels some of the more acrimonious geek debates.

 

What bothered me much more about the C64 (than colors ever could) were the crappy floppy drives.

I believe they ran at a sloth-like 300 characters per second/2400 bps or something like that.

 

Fastloaders both coded in later games and third party carts at first helped a lot. I don't remember the full story but I believe the default 1541 code was detuned purposely.

 

Also, Atari Basic seemed more user friendly (a bigger deal in those days, obviously). I should think these things matter more, and it seems inexcusable that the C64 wasn't superior in every way being years later in introduction.

 

Ah! But they didn't have the great Jay Miner and his design team until the Amiga (which is the true 16-bit successor to the A8. Engineering wise if not company wise. It is an irony that is also true of the C64 to ST).

 

I dunno. I always liked the different text colors on the C-64. It is actually a somewhat advanced bit of programming to make an A8 do textwise what any inquisitive kid can do on the C-64 at power on. In either case, I think that made little difference. I typed many the program in "on faith" so to speak on both my 800XL and a buddy's C64.

[Photo quality GTIA mode?]

The next step after that is to alternate the luma line. Have GR.10 every second frame, which then gives the apparent 160 horizontal resolution.

 

I've also been meaning to try something using GR.10 alternating as the colour line, but not sure that it would look any better.

 

How does having another 80 horizontal pixels resolution show a 160 horizontal pixel res.?

 

A timing bug in the GTIA causes GR 10 pixels to be off by half a color clock from either 9 or 11. If you alternate frames with either 9 or 11 then you see an apparent 160 pixels across.

[Photo quality GTIA mode?]

This is what I was looking for, thanks. Thanks to the rest of you as well. Time to do a little experimenting...

 

You may find the following of interest.

 

http://rjespino.tripod.com/8bit/colrjpeg/colrjpeg.html

 

Source is available.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Commodore never had any good marketting at all, just like Atari. It was the price (the cut-throat tramial stuff) and the games which sold the C64. Look below to see why this is so.

 

Agreed. It's just that the market was changing when Tramiel came into Atari. When Commodore was a young feisty computer maker, all the "home computers" simply cost too much. This includes our beloved A8s. The C-64 debuted expensive but was cheaper first and was of decent manufacturing standard. So Tramiel created a window of year or so in which to sell an inexpensive computer that could nonetheless play great games. In such a market, that strategy is correct if you can make the economies of scale work for you. That's what made the C-64 the 8-bit king.

 

Fast forward a few years and anyone who wants a home computer or a PC can probably afford one. In this era, you still need a C-64, A8, or an Apple II in a pinch because while they may have been higher-res CGA/Hercules make for some ugly looking barely animated game screens. But PCs get better all time, price floors have been established, and things called NES and Master System start showing up at the local K-Mart. Tramiel gives us the XE line which represents a major drop in build quality from the XL and when the ST comes out, similar materials and methods are used. For awhile, he tries to compete on price alone while the ST changes little until the Megas come out. The Amigas evolved and more than a token effert was made to keep up with the Macs and PCs.

 

That cutthroat IKEA approach is great when there is untapped market to conquer. In a mature market, there is an expectation of quality and an expectation of parity with competitive systems. That is what just he didn't seem to get at all. For a number of years, the most popular upgrade for the ST was a set of keyboard stiffening springs while Amiga owners had all sorts of cool funky stuff to buy. Tramiel just kept selling the same increasingly stale wine in the same bottles with different stickers.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Atari liked to keep their stuff secret. John Harris messed around with the A800 and wrote a excellent game IMO "Frogger". It goes to show what the 800 was capable of, but, according to him, he couldn't get anything out of Atari, he had to hack the machine to discover the secrets. I think the Commodore was more open, therefore, there are more C64 games... I like them both

 

The Atari wasn't all that secret after '81 or so when De Re Atari came out. Still Atari did sit on the true capabilities of the machine for three years. I believe much of the reason for this is in the original intentions for the ANTIC/GTIA/POKEY chipset. The A8 custom chips were initially intended for a 5200-like console and the machine was intended to pretty much be a "super 2600". The burgeoning market of Apple IIs, Pets, and TRS-80s and other micros changed the minds of the Atari brass so the 400/800 were designed around the chips instead.

 

How does this explain anything? Atari didn't divulge 2600 programming information at all initially. The idea of a third-party console developer was still new and didn't happen in a big way until Activision came along. Even though Atari wanted a computer to compete in the computer market, they were still thinking like a 70s game company accustomed to full control over hardware and software.

 

Once the C-64 hit the market, there was very little if any secrets about the A8. Although I'll grant that the C-64 came with MUCH better documentation, I don't think that explains the popularity of the C-64. Tramiel simply had better ideas for promoting the product and had the advantage of controlling MOS technologies. Pity he couldn't switch gears and quit thinking like a cutthroat mass marketer when HE got Atari.

[Atari Vs C64 --- 80s Computer scene etc chat...]

One thing I'm a little curious about - has anyone ever bothered to try to interface a 1541 disk drive to the Atari? Although these days it's a kinda pointless exercise due to things like APE, IDE interfaces and SIO2SD.

 

I suppose it could be done in principle but it would take a bit of software writing and you'd have to get the timings for the protocol from somewhere. I once used something called (I believe) x64 to connect a 1571 drive to a PC's parallel port. There was DOS software that you could use to write c64 disk images to the PC suitable for use in emulators. You could also write downloaded disk images to floppies. Since this project used some pins on the parallel port rather than the RS-232 port, it doesn't appear that interfacing a 1541 to j-random-serial-port is all that easy. You can use pins of a PC parallel port as a custom serial port if you want to interface a serial device that doesn't use RS-232 timings and you have the chops to code for a custom serial protocol.

 

I rescued a buddy's childhood C-64 disk collection this way. I also used Linux to pull the contents of his Amiga hard drive but that is another story .

[Photo quality GTIA mode?]

Does anyone know how to open/access the atari's photo quality GTIA mode? I've seen it done in Atari's photo demonstration disk, but can't remember how it is achieved? A small basic program (with m/l routine if required) would be most appreciative.

 

That sounds like (hope I don't mix these up) GTIA mode 9 which is 16 shades of one color at 80x192. There is also mode 11 which is 16 different shades at one luminance (80x192 again). Mode 10 is a tradeoff between those two but I don't remember how the compromise works. There are also software generated modes like HIP and TIP which can do better if you don't mind som e flicker. Since you aren't allergic to ML perhaps you may get a guru or two to fill you in on that. In any case, calling anything the A8 can accomplish "photo quality" is a real stretch.

[Atari Vs C64 --- 80s Computer scene etc chat...]

hires+16 colors comes with a price: no 128 color palette.c)

128 colors comes with a price: with no tricks you can only display 16 colors of the same shade, or 16 shades of the same color, in very lowres. (iirc)

 

its just a different compromise of the technique present at the day. you choose which do u prefer.

 

Slightly lower resolution seems a small price to pay for 8 times the color depth. Color is no less a figure of merit in detail than raw resolution.

 

what do you call a DMA ? C64's gfx chip uses quite a few hardwired different "direct memory acces" types for sprites, char data, etc, for which it stops the cpu, when its time to read the mem.

 

The video hardware can directly access any portion of the memory map just by flicking a pointer around and that can be done quickly enough to make some interesting things possible. What I call "DMA" is exactly that: direct access to any part of the memory map by the video hardware.

 

Less common and probably a lot harder to do are effects like the Rubik's Cube that solves itself in Numen

 

c64 is almost twice as slow as atari in that gfxmode. run numen at 50% speed in the emu and check that fx again, and you'll know why c64 demos dont do that often . its simply slow. however there are a few demos which do complicated 3d stuff going as far as phong shading with texturing at the same time. let me know if you want me to list them tho prolly you will need emu (most of them are not on youtube).

 

Sure. I have a recent version of VICE.

 

 

 

and what does that mean? I think the situation is quite similar: Both on Atari & c64 you usually start with coding your screenmode, when it comes to demos

 

It means that this machine was Jay Miner architecture like the first Amiga chipset. What you have is a scanline video generator whose operation can be changed at every scanline or some useful multiple of scanlines. This means there is hardware assist for switching palletes and hardware video mode at any arbitrary vertical point onscreen. Some of the best Atari effects don't mean just setting a screenmode and drawing on it. Things like HIP and TIP make software graphics modes possible. The entire color pallete can be put onscreen at once. It is possible to exploit bugs in the ANTIC/GTIA chipset and do limited mixing of modes in vertically as well. Basically, the Atari video hardware wasn't a dumb pixel buffer. It was a combination of a dumb scanline generator controlled by a simple video coprocessor.

 

dont think so, c64 was designed in less than a year including the chips. you can do whatever tho with the usage of the 'cartridge' port, as all important lines are routed out. guess its the same on a8.

 

Unfortunately that isn't true. Only with the addition of the PBI port were most important lines brought out. Still, many mods require getting inside the unit proper and there are very few items that utilize the PBI port.

[Atari Vs C64 --- 80s Computer scene etc chat...]

Yes, C64/128 has better text mode (whether 40 or 80 column) since it has a separate color memory area, but limited colors and sub-par pixel quality does not render it justice.

Actually, the text mode was most frequently used C64 for games. Combined with the hardware soft scrolling registers, the CPU could pretty easily soft scroll a whole screen.

 

What do you mean with "sub-par pixel quality"?

 

I have no idea myself but I've been wading through YouTube looking at C-64 and A8 demos. The things I notice over and over again are these:

 

The SID chip seems to have more raw capability than POKEY "timers" or no. There are more registers, more effects, and a flexible design directly modeled after the subtractive Moog and ARP synths of the day. While the C-64 video hardware seems less "diddlible" and plastic than the A8 video hardware, exactly the reverse is true of sound. Don't get me wrong, in the hands of the right deeply knowlegable programmer POKEY can do some amazing things. It can maybe even do a thing or two SID can't but the fact remains that POKEY is basically a set of polycounters connected to a simple DAC. The SID is a true albeit cutdown synth of the Moog/Prophet/ARP design school and I believe the E-Mu synths were a direct outgrowth. I pretty much have to hand the crown to the C-64 in sound.

 

The C-64's video on the other hand doesn't impress me nearly as much. I do notice that the C-64 can do very hi-res looking stills with no flicker and it can do hi-res at 16 colors with no tricks and more like 60 with tricks. But it suffers from a severely limited color pallete, no DMA, and the highest res modes seem to only be efficiently usable as character cells. Those little 8x8 boxes still seem to shine through despite some truly heroic coding. I also notice that even with extreme register diddling, dithering, frame swapping, sprite overlays, and who knows what else that the C-64 has trouble creating even the appearance of more than 60 colors or so. The effects in these demos seem to play to that hi-res strength so we see lots of highly chisled bumpmaps and finely detailed lissajous and so-forth. Less common and probably a lot harder to do are effects like the Rubik's Cube that solves itself in Numen. I do see rotating 3D type effects in the Commodore demos but they are harder to come by and less well developed. In the case of a demo like Drunk Chessboard, you see both high color-depth effects and at least the appearance of translucent 3D objects. I suppose the A8 may have a slight processor edge in addition to more deeply programmable video hardware. A friend of mine who was a big c64 head even said "Things on your Atari just seem to move more fluidly." Ballblazer was big favorite of his.

 

One interesting area I think C-64 may have some interesting edges in is multiprocessing and modding. Isn't it true that a clever C-64 coder can offload work to the processor in the 1541/1571 drives? The C-64's simpler video system gives it a moddability edge in another area. It seems that things like the SuperCPU (http://www.cmdweb.de/scpu.htm) are a lot harder to do for the A8 since the video timings are so closely tied to both processor and display. The internal design of the C-64 seems more modular and less integrated than the A8 making no end of crazy mods easier. I've seen various 65816 upgrades for the A8 discussed but they seem to have difficulty getting past the prototype stage and the common thread throughout all of them is that it is difficult to pull off without destroying compatibility in the process.

[ProSystem Emulator Update?]

I've been toying around with releasing a new version (version 2.0) that worked with SDL and/or Java (using JNI and C++ core).

 

That would make it interesting to me as I only use Windows in a virtual machine for work related stuff.

[ADAM EMULATOR.....WHERE CAN I FIND ONE?]

I'll throw in my 2 cents worth on ADAMEm, as well. Great emulator, but if you are running Windows XP or higher you may have some issues with the sound. It worked fine when I had Windows ME on my machine, but when I upgraded to Windows XP, the sound went in the toilet. Apparently it depends on what sound card you have. Under XP with my Sound Blaster Live 5.1 card, the sound is garbled and scratchy (again, it was fine under ME). But on my laptop with XP and an Altec Lansing sound card, the sound is fine.

 

This is why I mentioned running it with DOSBOX. You take a performance hit on slower machines but it does smooth out the problems you have running DOS apps on modern OSes. Being a Linux user, I get good use out of the X11 version but even there I had to resort to a hack to get it to run on my 32bpp desktop since it only likes 16bpp desktops.

 

Another possibility is to run it something like VMware Player or VirtualBOX.

[ADAM EMULATOR.....WHERE CAN I FIND ONE?]

dam! it sounds complicated. All I wanted to do was play the adam roms like donkey kong, jr and dragons lair. is it possible to play the adam versions on a regular coleco emmu?

 

Only if that game would run on an unaltered ColecoVision. The ADAM was a superset of the ColecoVision and one version of the ADAM was in fact an Expansion Kit for the ColecoVision.