4 ms·

Damnit I slipped and (mostly) built an Amiga 500

111 points by pabs3 4y ago

johnklos 4y ago
This is an excellent way to preserve classic machines. There are lots of projects out there for new PCBs, new accelerators, new replacements for Amiga custom chips and so on, just as there are new updates to AmigaDOS (up to 3.2.1, which was released last year). For example: https://github.com/endofexclusive/deniser https://github.com/endofexclusive/deniser https://github.com/LIV2/Bluster https://github.com/LIV2/Bluster https://github.com/jbilander/ReAgnus https://github.com/jbilander/ReAgnus https://www.tindie.com/products/bobsbits/a500-amiga-500-replica-pcb/ https://www.tindie.com/products/bobsbits/a500-amiga-500-repl... https://github.com/terriblefire https://github.com/terriblefire Add the PiStorm, and you've got multiple ways to keep old hardware running while enjoying advantages of new hardware. Lots of people are too young to remember using Amigas, but any programmer of modern systems could learn lots from seeing firsthand how incredibly efficient Amigas are.
- Jupe 4y ago
  > but any programmer of modern systems could learn lots from seeing firsthand how incredibly efficient Amigas are. Agreed. Much of the Amiga's OS was quite elegant in my opinion. Everything was reachable by a linked list. Start with AbsExecBase (0x00000004) and traverse the linked lists from there to find virtually anything/everything. (Intution objects included). If it wasn't for bit planes and lack of memory protection, I think it would have had a fighting chance (oh, and if not for C= incredibly horrific management).
  - unwind 4y ago
    Obviously, the lack of memory protection was what enabled the global AbsExecBase implementation to begin with. I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment, but not sure about how the details would look. Of course the highly integrated custom chips were also a great thing to have, and made very low-level programming fantastically easy and powerful. The OS was great, but there was also the almost parallel universe of low-level programming. When you hit the bare metal on an Amiga, it sings. And it sure felt like it had a fighting chance, it was easily the best computer platform for a number of years. Oh to be young again, and so on. :)
    - zozbot234 4y ago
      > I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment Fun thing, that's exactly how vDSO's work.
    - snvzz 4y ago
      >I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment, but not sure about how the details would look. The main issue is the passing of pointers to physical memory through exec messages. Of course, with a flag day and some virtualization to make up for it, it would have been possible to run old software on new hardware and a protected AmigaOS.
  - snvzz 4y ago
    >(oh, and if not for C= incredibly horrific management). I believe that to be the real, non-surmountable problem. Newer generations with better hardware and memory protection would have been totally possible. Virtualization could have taken care of backwards compatibility. Some practical modern examples include: - Whdload, which patch and wrap floppy-booted games so that they can run from the harddisk, allowing for returning back to multitasking when done, with optional MMU protection. - AROS, an AmigaOS-like open source OS, which can run classic Amiga software through reasonably well integrated emulation. - MorphOS, a PowerPC AmigaOS-like OS with similar slick emulator integration.
    - gpderetta 4y ago
      memory protection would be hard I think, right? The whole OS was based around message passing by just linking a message to the target process message port pointer. edit: but, as per your other comment, you know that. How do you see protection working in amigaOS? Just share the pages that are needed for messaging and protect everything else?
      - snvzz 4y ago
        A flag day would be needed. This means literally breaking the ABIs. New interfaces would take care of setting up shared memory or doing cross-space copying. There's always ways to deal with old software, such as through virtualization.
        erikarn 4y ago
        that's why the later OS releases after amiga/commodore imploded extended some of the memory APIs to say "This needs to be globally visible". That way you'd allocate message memory in globally accessible memory and the MMU could do "things". (Not that I'm a fan of that solution, just saying, they had to hack around it.) https://wiki.amigaos.net/wiki/Exec_Memory_Allocation https://wiki.amigaos.net/wiki/Exec_Memory_Allocation (I don't do later amigaos things though :-)
  - pjc50 4y ago
    > Everything was reachable by a linked list. Start with AbsExecBase (0x00000004) and traverse the linked lists from there to find virtually anything/everything. It sounds like this very openness is the problem - all of the benefits of AmigaOS involve processes reading one another's memory, and conversely modern OSs have to put so much effort into protecting the user from apps attacking one another.
  - tralarpa 4y ago
    > oh, and if not for C= incredibly horrific management Thanks to that horrific management, the future of the Amiga was dead the moment it was released. No significant update of the OS for five years (KS1.0 in 1985 to KS2.0 in 1990). No significant update of the hardware for seven years (Amiga 1000 in 1985 to Amiga 4000 in 1992). And that was while the IBM-compatible PCs and Windows were going through those years that established their dominance for the next decades.
    - icedchai 4y ago
      I remember upgrading to an A3000 from an A500. 1.3 and 2.0 were like night-and-day. The 3000 was a pretty big hardware leap in terms of integration, but you are right, it was still incremental. The chipset, which is what made the Amiga an "Amiga", barely changed. The 1200/4000 AGA machines were too little, too late. By that time, everyone was getting 386's with SVGA and Soundblasters.
      - snvzz 4y ago
        When the original Amiga team left Commodore, the next generation chipset, Ranger, was finished and ready. But CBM management decided to discard it. But that wasn't, by far, the only time they went directly against the architects' judgement. Like how they later forbid the A3000 team from using a DSP, or the fate of AA+/AAA.
  - zozbot234 4y ago
    The Amiga was ultimately tied to its m68k architecture. No matter what Commodore did, it would have become unviable as the m68k died and was no longer developed. There were other very interesting computers back then, including the ARM-based Acorn Archimedes. But they weren't the Amiga; if anything, they didn't have anything like its huge software library.
    - snvzz 4y ago
      >The Amiga was ultimately tied to its m68k architecture. >No matter what Commodore did, it would have become unviable as the m68k died and was no longer developed. AROS, Amithlon, MorphOS very much demonstrate in practice how untrue this is.
      - Thorham 4y ago
        Not to mention Apple with the Mac: 680x0 -> PowerPC -> X86/64 -> Arm
- snvzz 4y ago
  >deniser GPLv2, OSH, great. >Bluster CERN OHL 1.2, OSH, great. >ReAgnus CC-By-SA. Not the best license for hardware, but technically OSH. Good. >A500++ I understand directly based on A500+. Might be legally dodgy. But it is good that it exists, for preservation. >TerribleFire Mix of licenses in their projects. Some of them are OSH (great). But some of them are not, due to restrictions on commercial use and/or derivatives. From the above, I gather the one remaining big item that's not yet covered is the PAULA chip. It seems we're getting close to an open hardware chip-by-chip whole ECS Amiga remake.
  - erikarn 4y ago
    yup, the community is really coming together over this. I'm shocked and happily surprised. :-) There are gary / buster drop-ins now too. Super Buster has been talked about for Zorro-III, but yeah, the AGA and A3000 glue logic stuff hasn't yet been dropped in.
  - datpiff 4y ago
    >From the above, I gather the one remaining big item that's not yet covered is the PAULA chip. I think Minimig has had a GPL'd Paula implementation for like 15 years.
    - snvzz 4y ago
      Sure, it has. And minimig is great. But minimig is a standalone whole-amiga replacement. It is not a replacement for each individual chip. Paula has many functions, but some of them involve interfacing the analog world (floppy controller, UART, Audio). While a starting point, I don't think minimig's Paula is ready to go.
mrweasel 4y ago
There is a great series on YouTube about "Building the Worlds Newest A500". It looks to be the same PCB, but with a different case. Part 1: https://www.youtube.com/watch?v=ECu6i6WR7mo https://www.youtube.com/watch?v=ECu6i6WR7mo Part 2: https://www.youtube.com/watch?v=87q-TTG48Ew https://www.youtube.com/watch?v=87q-TTG48Ew Part 3: https://www.youtube.com/watch?v=Va91bISkpKI https://www.youtube.com/watch?v=Va91bISkpKI Part 4: https://www.youtube.com/watch?v=4EsRI-5fblM https://www.youtube.com/watch?v=4EsRI-5fblM
LightG 4y ago
Love this. Kind of inspired me to take another look at my Atari ST... good times.
- erikarn 4y ago
  ... as the OG author of this thread I should say I /did/ drop in a memory upgrade into my Atari 1040STF. :-) I should write a blog post about that too if I haven't already.
- kjs3 4y ago
  I've been kinda-sorta watching eBay for an ST to come along that's not to outrageous since I figure soon enough I can get a "new" Amiga. 68k hacking was good times, and it's nice to occasionally bang out some code on something relatively simple and understandable.
_joel 4y ago
Here's building a new 2000 in 2022 https://www.youtube.com/watch?v=NLhRbbE6Lz8 https://www.youtube.com/watch?v=NLhRbbE6Lz8
erikarn 4y ago
(ah crap i'm on hackernews!)
- cjk 4y ago
  Well-deserved, friend!
quotha 4y ago
Damnit is a common misspelling of dammit.
_-----_ 4y ago
The timing of this is really good. I just finished watching a video about restoring an Amiga's case: https://www.youtube.com/watch?v=ACj7P5oOlHw https://www.youtube.com/watch?v=ACj7P5oOlHw

111 points by pabs3 4y ago

This is an excellent way to preserve classic machines. There are lots of projects out there for new PCBs, new accelerators, new replacements for Amiga custom chips and so on, just as there are new updates to AmigaDOS (up to 3.2.1, which was released last year). For example: https://github.com/endofexclusive/deniser https://github.com/endofexclusive/deniser https://github.com/LIV2/Bluster https://github.com/LIV2/Bluster https://github.com/jbilander/ReAgnus https://github.com/jbilander/ReAgnus https://www.tindie.com/products/bobsbits/a500-amiga-500-replica-pcb/ https://www.tindie.com/products/bobsbits/a500-amiga-500-repl... https://github.com/terriblefire https://github.com/terriblefire Add the PiStorm, and you've got multiple ways to keep old hardware running while enjoying advantages of new hardware. Lots of people are too young to remember using Amigas, but any programmer of modern systems could learn lots from seeing firsthand how incredibly efficient Amigas are.

Jupe 4y ago
> but any programmer of modern systems could learn lots from seeing firsthand how incredibly efficient Amigas are. Agreed. Much of the Amiga's OS was quite elegant in my opinion. Everything was reachable by a linked list. Start with AbsExecBase (0x00000004) and traverse the linked lists from there to find virtually anything/everything. (Intution objects included). If it wasn't for bit planes and lack of memory protection, I think it would have had a fighting chance (oh, and if not for C= incredibly horrific management).
- unwind 4y ago
  Obviously, the lack of memory protection was what enabled the global AbsExecBase implementation to begin with. I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment, but not sure about how the details would look. Of course the highly integrated custom chips were also a great thing to have, and made very low-level programming fantastically easy and powerful. The OS was great, but there was also the almost parallel universe of low-level programming. When you hit the bare metal on an Amiga, it sings. And it sure felt like it had a fighting chance, it was easily the best computer platform for a number of years. Oh to be young again, and so on. :)
  - zozbot234 4y ago
    > I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment Fun thing, that's exactly how vDSO's work.
  - snvzz 4y ago
    >I guess it would be possible to implement as a shared read-only page mapped into each process in a protected environment, but not sure about how the details would look. The main issue is the passing of pointers to physical memory through exec messages. Of course, with a flag day and some virtualization to make up for it, it would have been possible to run old software on new hardware and a protected AmigaOS.
- snvzz 4y ago
  >(oh, and if not for C= incredibly horrific management). I believe that to be the real, non-surmountable problem. Newer generations with better hardware and memory protection would have been totally possible. Virtualization could have taken care of backwards compatibility. Some practical modern examples include: - Whdload, which patch and wrap floppy-booted games so that they can run from the harddisk, allowing for returning back to multitasking when done, with optional MMU protection. - AROS, an AmigaOS-like open source OS, which can run classic Amiga software through reasonably well integrated emulation. - MorphOS, a PowerPC AmigaOS-like OS with similar slick emulator integration.
  - gpderetta 4y ago
    memory protection would be hard I think, right? The whole OS was based around message passing by just linking a message to the target process message port pointer. edit: but, as per your other comment, you know that. How do you see protection working in amigaOS? Just share the pages that are needed for messaging and protect everything else?
    - snvzz 4y ago
      A flag day would be needed. This means literally breaking the ABIs. New interfaces would take care of setting up shared memory or doing cross-space copying. There's always ways to deal with old software, such as through virtualization.
      - erikarn 4y ago
        that's why the later OS releases after amiga/commodore imploded extended some of the memory APIs to say "This needs to be globally visible". That way you'd allocate message memory in globally accessible memory and the MMU could do "things". (Not that I'm a fan of that solution, just saying, they had to hack around it.) https://wiki.amigaos.net/wiki/Exec_Memory_Allocation https://wiki.amigaos.net/wiki/Exec_Memory_Allocation (I don't do later amigaos things though :-)
- pjc50 4y ago
  > Everything was reachable by a linked list. Start with AbsExecBase (0x00000004) and traverse the linked lists from there to find virtually anything/everything. It sounds like this very openness is the problem - all of the benefits of AmigaOS involve processes reading one another's memory, and conversely modern OSs have to put so much effort into protecting the user from apps attacking one another.
- tralarpa 4y ago
  > oh, and if not for C= incredibly horrific management Thanks to that horrific management, the future of the Amiga was dead the moment it was released. No significant update of the OS for five years (KS1.0 in 1985 to KS2.0 in 1990). No significant update of the hardware for seven years (Amiga 1000 in 1985 to Amiga 4000 in 1992). And that was while the IBM-compatible PCs and Windows were going through those years that established their dominance for the next decades.
  - icedchai 4y ago
    I remember upgrading to an A3000 from an A500. 1.3 and 2.0 were like night-and-day. The 3000 was a pretty big hardware leap in terms of integration, but you are right, it was still incremental. The chipset, which is what made the Amiga an "Amiga", barely changed. The 1200/4000 AGA machines were too little, too late. By that time, everyone was getting 386's with SVGA and Soundblasters.
    - snvzz 4y ago
      When the original Amiga team left Commodore, the next generation chipset, Ranger, was finished and ready. But CBM management decided to discard it. But that wasn't, by far, the only time they went directly against the architects' judgement. Like how they later forbid the A3000 team from using a DSP, or the fate of AA+/AAA.
- zozbot234 4y ago
  The Amiga was ultimately tied to its m68k architecture. No matter what Commodore did, it would have become unviable as the m68k died and was no longer developed. There were other very interesting computers back then, including the ARM-based Acorn Archimedes. But they weren't the Amiga; if anything, they didn't have anything like its huge software library.
  - snvzz 4y ago
    >The Amiga was ultimately tied to its m68k architecture. >No matter what Commodore did, it would have become unviable as the m68k died and was no longer developed. AROS, Amithlon, MorphOS very much demonstrate in practice how untrue this is.
    - Thorham 4y ago
      Not to mention Apple with the Mac: 680x0 -> PowerPC -> X86/64 -> Arm
snvzz 4y ago
>deniser GPLv2, OSH, great. >Bluster CERN OHL 1.2, OSH, great. >ReAgnus CC-By-SA. Not the best license for hardware, but technically OSH. Good. >A500++ I understand directly based on A500+. Might be legally dodgy. But it is good that it exists, for preservation. >TerribleFire Mix of licenses in their projects. Some of them are OSH (great). But some of them are not, due to restrictions on commercial use and/or derivatives. From the above, I gather the one remaining big item that's not yet covered is the PAULA chip. It seems we're getting close to an open hardware chip-by-chip whole ECS Amiga remake.
- erikarn 4y ago
  yup, the community is really coming together over this. I'm shocked and happily surprised. :-) There are gary / buster drop-ins now too. Super Buster has been talked about for Zorro-III, but yeah, the AGA and A3000 glue logic stuff hasn't yet been dropped in.
- datpiff 4y ago
  >From the above, I gather the one remaining big item that's not yet covered is the PAULA chip. I think Minimig has had a GPL'd Paula implementation for like 15 years.
  - snvzz 4y ago
    Sure, it has. And minimig is great. But minimig is a standalone whole-amiga replacement. It is not a replacement for each individual chip. Paula has many functions, but some of them involve interfacing the analog world (floppy controller, UART, Audio). While a starting point, I don't think minimig's Paula is ready to go.

mrweasel 4y ago

There is a great series on YouTube about "Building the Worlds Newest A500". It looks to be the same PCB, but with a different case. Part 1: https://www.youtube.com/watch?v=ECu6i6WR7mo https://www.youtube.com/watch?v=ECu6i6WR7mo Part 2: https://www.youtube.com/watch?v=87q-TTG48Ew https://www.youtube.com/watch?v=87q-TTG48Ew Part 3: https://www.youtube.com/watch?v=Va91bISkpKI https://www.youtube.com/watch?v=Va91bISkpKI Part 4: https://www.youtube.com/watch?v=4EsRI-5fblM https://www.youtube.com/watch?v=4EsRI-5fblM

LightG 4y ago

Love this. Kind of inspired me to take another look at my Atari ST... good times.

erikarn 4y ago
... as the OG author of this thread I should say I /did/ drop in a memory upgrade into my Atari 1040STF. :-) I should write a blog post about that too if I haven't already.
kjs3 4y ago
I've been kinda-sorta watching eBay for an ST to come along that's not to outrageous since I figure soon enough I can get a "new" Amiga. 68k hacking was good times, and it's nice to occasionally bang out some code on something relatively simple and understandable.

_joel 4y ago

Here's building a new 2000 in 2022 https://www.youtube.com/watch?v=NLhRbbE6Lz8 https://www.youtube.com/watch?v=NLhRbbE6Lz8

erikarn 4y ago

(ah crap i'm on hackernews!)

cjk 4y ago
Well-deserved, friend!

quotha 4y ago

Damnit is a common misspelling of dammit.

_-----_ 4y ago

The timing of this is really good. I just finished watching a video about restoring an Amiga's case: https://www.youtube.com/watch?v=ACj7P5oOlHw https://www.youtube.com/watch?v=ACj7P5oOlHw