Questions tagged [amiga]

For questions related to the Commodore Amiga family of personal computers.

Filter by
Sorted by
Tagged with
7
votes
4answers
2k views

Amiga memory bandwidth

Looking at a timing diagram for the various kinds of memory access occurring on the Amiga http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node02D4.html it seems to be saying that video ...
2
votes
1answer
166 views

How to get started with writing drivers for amiga OS

I would like to learn how to write drivers for Amiga OS. Seems like a daunting task, but I have spare time and I find great value for amiga (CDTV) community in particular. Currently if a CD ROM breaks ...
6
votes
2answers
226 views

Amiga OS 3.1 vs 3.5 vs 3.9 system difference

I'm trying to find some resources on different versions of Amiga OS (aka Workbench) especially if there were any major changes to the OS architecture, resource use and drivers (with a goal to make ...
27
votes
5answers
3k views

Why is the Amiga ROM at a high memory location, and RAM in low memory?

When a 68000 CPU powers up, it reads a few words at memory location zero to get the initial stack pointer and program counter. That suggests to me that a computer system designer would put the system ...
5
votes
1answer
187 views

Could the Apple IIGS play any and all Amiga MOD files?

The Apple IIGS has a wavetable synthesis sound chip with dedicated 64 kilobytes of RAM. I assume the sound architecture dictates that samples have to be loaded into that dedicated RAM to be able to be ...
9
votes
2answers
578 views

Identify this Amiga game: It's just like Rocket League

I remember playing an Amiga game which was very similar to Rocket League, subject to the technology of the time. It was a two player game with a top-down 2D playing area. There was a large puck ...
8
votes
3answers
598 views

Why does the Amiga 500 have half the HSYNC pulses seperately compared to those in CSYNC?

After many years I bought myself a new old Amiga 500 (rev 5) and wanted to hook it up to an LCD monitor (Samsung Syncmaster 152N) that has a VGA input. I tried hooking it up directly by making an ...
20
votes
2answers
935 views

How was 8-channel audio achieved on Amiga?

Oktalyzer was a Tracker style program for Amiga, that allowed composing and playing music with 8 channels instead of the "hardware-natural" 4. So far I learned it achieved that by splitting the 4 8-...
12
votes
5answers
2k views

How and why did Intel make the PCI bus “CPU Agnostic”?

Intel invented the original 32/64-bit PCI bus in the early 1990s to replace the decade old ISA bus used in PC's. It was immediately popular (in comparison to Micro Channel or EISA), being both faster ...
11
votes
2answers
943 views

Why was Windows 3.1 so dreadfully slow on an Amiga A2286 bridgeboard?

Back in the day I had an Amiga 2500/30 with an A2286 as my "swiss army knife" home computer; not only did I have the ability to run MacOS (ShapeShifter) at native speed, but the 8MHz 286 bridgeboard ...
0
votes
1answer
145 views

CF partitions not showing up in Workbench

4GB Compact Flash KS 3.1 40.68 WB3.1 Latest WinUAE I just created a Compact Flash (compatible Transcend) partitions under Workbench on latest WinUAE using this guide. Despite following the steps my CF ...
4
votes
2answers
156 views

Joystick adapter from 9-pin to USB

I have still a couple of old C64/Amiga joysticks and I'd like to use them on the New C64, which has USB ports. Is there an adapter from 9-pin male to USB? This 3-year old article references a company ...
17
votes
3answers
949 views

Where are the blueprints of MOS chips?

Atari historians have been able to find documents and tapes of chips and hardware developed at Atari. E.g. http://atariage.com/forums/topic/154479-new-gtia-chips/ . Nothing like this is happening for ...
5
votes
1answer
404 views

On Amiga, what happens when I write to $DFC5A0 by mistake?

I'm fixing a game (TV Sports Basketball) that tries to write in audio data (using the range $DFF0A0 to $DFF0D0) but for some reason (bad programming), the index is sometimes (not always) bogus MOVEA.L ...
35
votes
4answers
8k views

Why didn't Apple sue Commodore over the Amiga's GUI?

Famously, in the late 1980's Apple sued Microsoft over the "look and feel" of Windows 2.x. The claim was that Windows breached Apple's copyright by being too similar to the Mac UI. Apple ultimately ...
20
votes
1answer
2k views

Who ended up owning Commodore's semiconductor IP?

The question of ownership of Amiga-related intellectual property post-Commodore is famously difficult to answer. My question is: does anyone "own" Commodore's semiconductor IP now, and if so,...
12
votes
2answers
1k views

Should I use the internal or external drive for loading Amiga 500 games?

I have a working (I think) Amiga 500 system with an internal DF0 drive and an external DF1 drive. The Amiga 500 powers up with Workbench v1.3. Can anyone tell me how to access a game disc (Marble ...
5
votes
1answer
224 views

How does DMACON/R registers on Commodore Amiga platform work?

I have a specific question about the DMACON/R registers found in Commodore Amiga range of computers. As you may know they are the DMA control registers that controls all the DMA channels used by the ...
1
vote
1answer
99 views

Help in finding signals on schematics

Where are the missing signals that I can't pair between amiga external drive connector and gotek drive? I'd like to connect GOTEK to CDTV, there is a way to do it directly (caddy died), but I can't ...
25
votes
6answers
27k views

How can you connect an Amiga 500/600/1000/2000 to a modern monitor?

I have an Amiga 500 that I'd like to get up and running again, but the 1084 monitor with which I used to use it has flyback transformer issues. What options are available to hook it up to a modern ...
11
votes
4answers
993 views

Amiga floppy disks and GCR vs MFM

According to the Wikipedia article on GCR, the Commodore 1541 disk drive used a particularly efficient GCR encoding scheme to cram 170K onto the same 5.25" disks that in an Apple drive only ...
21
votes
4answers
1k views

Does the “Amiga Client for Novell NetWare” exist?

On page 139 of Brian Bagnall's book "Commodore: The Final Years", there is the statement that at CeBIT Hannover in March 1989, Commodore announced (amongst other things) "Novell Netware for Amiga". I ...
25
votes
4answers
2k views

What exactly was the Amiga Ranger?

Amiga's history includes something called "Ranger" that supposedly was either meant to be the next generation system to be released after the Amiga 1000 was released, or the codename for the next ...
21
votes
7answers
3k views

Was Amiga the last of the home retrocomputers sold?

The Commodore-Amiga was offered for sale to home users from 1985 (original A1000 in North America) until 1996, when Escom stopped selling the A1200. By 1996, Apple was selling PowerPC-based Macs for ...
5
votes
0answers
233 views

What are the needed jumper settings for a 68060 accelerator for an Amiga 3000T?

I'm trying to install a 68060 accelerator on an Amiga 3000T, but I cannot figure out the correct jumper settings. The information I've found online is: J100 CLK90 Delay jumper. This Jumper has three ...
9
votes
2answers
446 views

How do I tell vasm to allow white spaces?

I have recently been learning to use vasm. For those that don't know, vasm is a cross-platform assembler for multiple types of processors such as the M68000. http://sun.hasenbraten.de/vasm/ I am ...
23
votes
2answers
4k views

How to convert Amiga DMS to ADF?

Our demoscene group managed to release only one demo before it fell apart, but these being the early days of the Internet in my country, and me getting lucky with obtaining access to it and creating ...
53
votes
7answers
21k views

Why was the Kickstart 1.x “Insert floppy” graphic so bad?

Anyone who used an pre-Kickstart 2.0 Amiga will be very familiar with the "Insert Workbench floppy" image: I realise that this is subjective, but the image has always stuck me as ... well, a bit ugly....
25
votes
4answers
4k views

Why does MP3 audio decoding overwhelm retro CPU's?

Many retrocomputers from the late 80s and early 90s had audio DAC hardware support. This includes the Amiga, Classic Macintosh, and PC's with SoundBlaster add-on cards. Despite the fact that the MP3 ...
29
votes
3answers
3k views

How can I recover the contents from an Amiga HDD using modern Linux?

I have two Amiga 1200's in pieces. One of them has a 52mb HDD in it and on it is my dissertation from 1995 and all my essays. I want to retrieve the dissertation because it's the only surviving copy. ...
6
votes
2answers
958 views

Attaching a CD-rom drive for Amiga 500

How can you attach a CD-ROM drive to an Amiga 500? Will any external SCSI drive do? Are drivers necessary and available?
8
votes
1answer
289 views

How Amiga A590 autoboot ROM and bootable floppy disk works?

Commodore A590 was a peripheral hard drive and memory expansion unit for Amiga 500/500+ computers. It provides SCSI and XT-harddrive controller and 2MB Fast Ram. Here is the Big Book of Amiga Hardware ...
4
votes
1answer
253 views

What is the largest RAM expansion for Amiga or Commodore? [closed]

What is the largest RAM expansion being manufactured today for Amiga and Commodore 8-bit?
9
votes
1answer
281 views

Amiga ed removes flags

Recently I noticed a strange behavior when editing startup-sequence with ed. Unless I call protect startup-sequence rwed before editing it, ed says unable to write the file. Saving the file ...
6
votes
1answer
349 views

How are Amiga Kickstart Relocation Files (.RTB) created?

Examples of Amiga Kickstart files (ROMs) can be 256k (1.2/1.3) or 512k (3.0/3.1) binary files, located at $FC0000-$1000000 or $F80000-$1000000 Several programs are able to "soft-kick" Amigas, i.e. ...
20
votes
5answers
6k views

Were the custom chips in the Amiga exploited for their hardware bugs like the ones in the C64 and Atari 8 bit computers were?

Here we are some decades on from the C64, and other 8 bit computers. New ideas that resulted in some new graphics effect or mode seem to happen, though we may be near the end of all that. Took a ...
14
votes
2answers
2k views

What options were available for having an Amiga 1000 not be dependent on a KickStart disk?

I bought an Amiga 1000 second-hand many years ago for $50. In this deal I received a spare motherboard as the one installed in the chassis was upgraded; most notably, it had KickStart on ROM and thus ...
1
vote
0answers
992 views

How many Amiga 590 units were sold?

The A590 was an external hard disk for the Amiga 500, in 'sidecar' form factor, that could also hold an extra megabyte of RAM. How many 590s were sold, throughout its life?
4
votes
1answer
177 views

pfs3 error when copying files

Config: WinUAE 4.2.1, CPU 68020, 24bit, FPU 68882, 8MB FastRam Z2, A1200, CF 4GB Transcend, BetterWB 43, Dopus 4, When I try to copy folders from PC to CF Partition (2.4GB, pfs3) it goes alright, ...
13
votes
4answers
3k views

Amiga 500 OCS/ECS vs Mega Drive VDP

Superficially the Amiga 500 and Mega Drive are similar. Both run a Motorola 68000 CPU at similar clocks and both have dedicated hardware for sprite and other graphics operations. Comparing the arcade ...
12
votes
2answers
1k views

Replacing the floppy drives in my Amiga 3000

My Amiga 3000 is starting to show its age, and recently one of the two internal floppy disk drives appears to have given up the ghost... I'd like to replace the drive but the A3000 case doesn't have ...
30
votes
5answers
4k views

What were the differences in floppy disk formats between Amiga and IBM/PC compatible computers?

The capacity in Amiga Old File System format (OFS, OS version 1.x) was 840KB, with the Fast File System ("FFS" (!)) introduced for OS 2.x onwards able to store 880KB. The PC format stored 720KB on the ...
8
votes
2answers
535 views

Create an Amiga hard disk image

I'm looking for Linux dd command equivalent for Amiga to make image of hard disk. TSGUI not work if disk have broken RDB. Do you know program which can make hard disk image on Amiga?
21
votes
3answers
2k views

Why was it not possible to cost-reduce the Amiga 500?

According to 'Commodore: The Final Years' (whole trilogy highly recommended, BTW), page 129, 'Jeff Porter realized it would not be possible to significantly cost reduce the Amiga 500 to get it into ...
15
votes
1answer
407 views

What does the H protection bit mean under classic AmigaOS?

The AmigaOS file protection bits allows for Read, Write, eXecute, Delete permissions on files, similarly to Unix (save for the Delete permission). Additional bits are Archive (reset when a file is ...
8
votes
1answer
688 views

How do specify drives to mount when Amiga 1200 starts up

I have an Amiga 1200 with an SD card and Classic WB installed. I have four drives DH0, DH1, DH2, DH3, when I start the machine with workbench it mounts all devices. If if start the machine using skip ...
59
votes
2answers
18k views

What is the “two-drive trick” that can read Amiga disks on a PC?

Standard belief is that the floppy disk controllers used on PCs are incapable of reading Amiga floppy disks, due to the PC disk controller expecting a very specific low-level format of disks, whilst ...
11
votes
2answers
533 views

Amiga Video Toaster support

What features of the Amiga chipset architecture and/or Amiga OS made it possible to design the Video Toaster for the Amiga? Why weren't there similar (cost-effective) video products for the PC or Mac?...
17
votes
1answer
999 views

Can you split resolutions and scrolling (horizontally) on an Amiga?

Some time back I asked if it was possible to get more than 8 sprites on a single scanline with the Amiga using a copper list. It seems it is quite possible indeed! Now I am wondering if it is ...
11
votes
4answers
1k views

What graphics sytems used display lists?

As near as I can tell, there seems to have been roughly speaking two schools of thought when it comes to graphics hardware among early consoles, what I will call the Atari and Texas Instruments ...