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57

The limitation is based on saving precious space on the 8 KiB boot ROM for the Amiga 1000. Before the "Insert Workbench" graphic ever graced an original Amiga 1000 from 1985, a user would first have to get past the "Insert Kickstart" screen. Since the original Amiga 1000 lacked any Kickstart in ROM, this initial image had to be stored in the very limited ...


45

Low number of bit planes (few colors) and low resolution saves kickstart ROM space as stated in the other answer(s). Another reason for the simplicity of the picture could be the limitation of available drawing tools when the kickstart logo was created. Considering the following to really be a post by the original artist Sheryl Knowles, creation of such an ...


36

While some lawyers do occasionally file lawsuits based mainly on their targets having "deep pockets", like Microsoft had, this is not generally successful. In order for a typical corporate lawsuit to gain any traction in the court, the plaintiff must provide sufficient "standing". In order to establish standing, Apple sought to convince the court that ...


28

The "Amiga Client Software for Novell Netware v1.4" (official name) was created in 1992 by Oxxi. It is available as a set of six(6) floppy disk images most places where Amiga abandon-ware is found. For instance, it can be found in the TOSEC Amiga archive. Commodore Amiga [TOSEC v2012-04-10]/Applications/[ADF]/Commodore Amiga - Applications - [ADF] (TOSEC-...


25

The Amiga OCS was not exploited in the same way as the C64's VIC-II simply because the OCS was designed from the beginning to support rapidly changing video output modes. Unlike the C64, and most 8-bit machines, the Amiga's display coprocessor (the "Copper") existed to allow display mode updates to occur many times during the raster. For machines like the ...


25

Amiga 500 1.3 machine only boots on drive 0 (DF0:) by default. There are programs that make it able to boot on DF1: but they're not really interesting because a lot of games either: have physical copy protection (even cracked copies can have some bits remaining and demand a disk in drive 0) have non-OS compliant track loader which only searches the disk in ...


23

If one game would qualify, that would be Alien Breed: the game switches from PAL to NTSC rapidly to emulate a damaged CRT display (extract of longplay at this point). A PAL to NTSC switch should occur at the top of a frame, so doing that in the middle of a frame can be considered like exploiting a bug. Now, whereas games didn't push the tricks too far, that ...


20

Splitting the screen on an X coordinate is more involved since you'd naturally end up with some garbage at the instant you changed from one to the other. But since the copper can be instructed to WAIT accurately, the garbage would be very predictable. If you covered that with a hardware sprite, you could have two vertical views, which is exactly what you get ...


20

TL;DR The ownership issue is really associated with the trademarked brand and product names, and the copyrighted ROM software, not the processor/co-processor hardware. I think there are two mainstream products who's licensing terms are instructive to understanding how the earlier (non-Amiga) Commodore IP has been used and defended by the new rights holders ...


19

A solution like that already exists: it's called vamos (Virtual AMiga OS) and emulates a 68k CPU and a bunch of libraries - enough to get terminal only programs (like compilers and assemblers) running: https://github.com/cnvogelg/amitools Not all that easy to setup though.


18

I'm assuming the screen resolution was the standard OCS 320x200 (or 320x256 for PAL): was there a technical reason for the image being so chunky, Chunky? Well, it's as usual in the eye of the beholder. But lets look at some issues: Any picture chosen should be usable in all screen modes, as it's unknown what mode the machine has to come up With more ...


17

Looking at the actual code, the iconic KS1.x Workbench disk-hand image is technically drawn as vector art — except for the texts, which are bitmaps. The machine-language code uses a simple “program” — stored in an array — to draw the different parts of the diskette, hand, and the fingers, run-time. This “DSL” implements three commands: Draw a polyline. ...


16

'Jeff Porter realized it would not be possible to significantly cost reduce the Amiga 500 to get it into the $250 retail price range'. They could have cost-reduced the A500 - perhaps even to $250 retail - but they would have had to make some compromises that (thankfully) they weren't willing to do. There were a lot of chips on the board. They needed ...


16

Short Answer: At the time PCI was devised, the x86 bus had already gone a long way toward being less chip specific. PCI is maybe a clean design, but some choices for signals are still 'intelish' Moving bus definition from following what a certain CPU implementation needs toward a more generic structure opens up more ways for future CPU development than ...


15

And now here are some really non-trivial hacks played with amiga chipset: 7-bitplane ECS hack: https://groups.google.com/forum/#!topic/comp.sys.amiga.misc/HQBzx6E0K1Y (see the first message in the topic) When you fill register $dff100 with value which has the number of bitplanes specified as 7 (lo-res) something strange is going on. On screen you will ...


14

They did, with the A600. But in true late-stage Commodore fashion, they screwed it up and made it more expensive. To cost-reduce an A500, you'd have to reproduce its spec on simpler silicon. The market wasn't interested in an 8 MHz 68000 in 1991/92: the PC had stolen all of the Amiga's thunder at commodity prices. The Amiga's niche silicon was just too ...


13

It may have been a combination of hubris and legal prudence on Commodore's part; per Commodore: The Amiga Years: The Amiga designers wanted something more original than [Berkeley Softworks'] proposal. "This may have been unfair, but part of it was we thought GEOS looked too much like a Mac; a color Mac before there was a color Mac," says [Dale] Luck. "It ...


12

The early-to-mid 1990s was a time where the future of the Personal Computer was very much up for grabs. Both the "Wintel" monopoly as a whole, and each part individually, where not at all set to be the foundations of the future PCs. Even if we were to assume that x86 would "win", we had OS/2 and to a lesser extent BeOS as competitors on ...


11

The Super Nintendo Entertainment System (called Super Famicom in Asia) is mostly TMS9918-like. However, the CPU's integrated memory controller has its own counterpart to Amiga COPPER, called HDMA (horizontal blanking direct memory access). HDMA can reprogram PPU registers during hblank based on up to eight lists stored in work RAM. Each HDMA channel has ...


11

The Amiga 500 has a very console-like experience for the most part when it comes to games. Treat DF0:, the internal drive, like you would the cartridge slot of a Super NES or a Sega Genesis. Just put your game into the internal drive and let the Amiga boot from it. :) You can either leave the game in the drive and power the machine on, or alternatively you ...


9

In analog TV, there was such thing as interlace. Roughly speaking, it kind of increased vertical resolution by putting scanlines of one "halfframe" (the one that lasts 20ms or goes 50 times per second, or, alternatively, 16.6ms and 60 Hz) between the scanlines of previous halfframe (saying scanlines I mean lines lit by electron beam on CRT). As the ...


8

I've been asked several times about discovered "interesting behavior" of the OCS chip set when the registers were updated at certain times in a certain order (at a certain rate, etc.), and whether that behavior was intentional or not. Simple stuff like changing modes or palettes synchronized to the NTSC "beam" was certainly intended. But I am also ...


8

A bit of web searching finds a site offering it. I have no idea if the site is legitimate or safe.


8

Yes, you can use -phxass option (name of the old Amiga native assembler by Phx/Frank Wille who is also the author of the Motorola syntax module) vasm -phxass -m68020 -kick1hunks -Fhunkexe -o test.exe main.asm From the documentation: ‘-phxass’ PhxAss-compatibility mode. Only directives known to PhxAss are recognized. Enables the following features: Enable ...


8

note: I'm answering my own question after more research and experimentation. The $DFF000 base is the custom chip register base address recommended by Commodore. But many other base addresses work. Some address lines select the custom chip base, and some are ignored. The custom chip address area is DF0000-DFFFFF so any base like $DFx000 works. This is ...


8

The extreme example is pure floating point calculations. Analogue electronics simulations, some kinds of 3D graphics rendering, statistical machine learning, huge spreadsheets, and so on. The comp.sys.m68k FAQ gives 264 kFLOPS for the 68882 at 25 MHz. The 68030 runs about 8 MIPS (integer) at 25 MHz. The source code for Linux's m68k floating point ...


8

As an example, years ago I installed a 25MHz 68030RC / 68851 / 68882 8MB accelerator in my A1200. First thing I did was use Realsoft Real 3D 1.x ray tracing program to render the teapot project. I rendered it using the standard program(1), then the FPU version. From what I remember, using the FPU version of Real 3D, the speed up was about 3 to 4 times faster....


7

If both the blitter's vertical and horizontal filling mode was enabled and launched on a stray pixel it created a simple fractal image known as the Sierpinski triangle. It can be seen in use in the 4K intro Heartcore by Delon. Another famous trick was rewriting BPLCON1 (the copper scroll register) to emulate a zooming effect as seen in many Sanity demos ...


7

I don't think the list is very long. The history starts with the Atari 2600, which was firmly derived from older discrete logic but added a microprocessor primarily for raster racing: doing so is the only means to draw a 2d frame — it's not a clever way to get more from the system, it's the intended use of the system. That was consolidated as a dedicated ...


7

In order to autoboot any Amiga hard disk, 3 things are needed. A version of Kickstart that supports boot from HD. This means >= Kickstart 1.3. A device driver that knows how to speak to the HD controller, such as scsi.device. A filesystem handler that understands the format of the HD. I think #1 is simple to understand. This is a function of the Strap (as ...


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