Is the Amiga architecture still relevant today?

[Lockon_15]

To answer the initial post question.
No, it's both surpassed and irrelevant.
 
Surpassed by competition (to pay respect of certain era).
Irrelevant by comparing scope of engineering process and computing concepts.
IMHO, if CBM eventually made it through stock horror, it would still get nailed few years later. Demise in 1994 has roots in 1989, maybe even earlier.
 
Maybe in some other dimension...

[Lockon_15]

@ejstans
 
A500 is a great example of technology compromise Bloodline mentioned.
To be aware of what that actually means you have to know A1000 well in detail.
A500 - It wasn't designed for major upgrade path in mind, since for that purpose there was A2000 launched side by side. That crappy (as you said) trapdoor expansion was not part of Agnus upgrade either, but wise engineering made i.e. slow>chip ram hacks feasible at field service level. If you take a good look on various A500 revisions, you'll see the impact of cost economy on motherboard design - first revisions (Rev3 & 5) had then expensive DIL DRAM covering the whole lower left area for just a mere 512Kb of ChipRAM. In spite of hacks, I don't really belive CBM left trapdoor bus just to allow ChipRAM increase somewhere in future, when RAM price drop occur. It was a best-fitting solution for that time - it wouldn't compromise FastRAM bus; it won't help you with ChipRAM, but it may persuade Amiga development to start using. And it did in great exent, just after Kickstart v1.3 debut. Later revisons introduced cheaper DIL RAM with more capacity, which made platform even more attractive for modding. A500+ went to the edge, preparing for full 2Mb ChipRAM at the cost of trapdoor slot. So, in some way, CBM closed the circle.
 
If the crowd was left with true FastRAM only, platform wouldn't attract more audience than A1000 and there would be no A1200 nor else.
AFAIK, A500 trapdoor 512Kb expansion might be the most selling Amiga peripheral.

[Lockon_15]

OK.
I'm not 100% sure, but getting trapdoor to Zorro bus while leaving sidecar open for expansion would involve Buster which is no-go for entry level A500. Moreover, as you already know, all trapdoor expansions above 512Kb were built with so called "Gary adapters" which provided missing address signals needed for bank switching. The most advanced of those were designed to host 4Mb RAM which was used as part-Chip, part-Slow combo, never true Fast. I found this case most convincing on the issue of trapdoor mapped to Zorro bus.
 
Next, price difference - trapdoor vs sideslot (sidecar, whatever). Of course they were expensive - in 80% of cases they came as a secondary or tertiary feature, alongsinde SCSI/IDE controller or more potent CPU (020/030). A500 made it's fame through gaming which requirred stock 68000 and 1Mb RAM, untill 1991. Who needs 68020 and harddrive, out of productivity purposes ? For that matters, you go for big box Amigas.
 
When I said "... was left with true FastRAM only...not attract more audience... " I meant that trapdoor FastRAM was not feasible and that if there were no other alternative, all those pricey sideslot expansions would make A500 just another A1000. Does this makes any more sense at all ?

[Lockon_15]

Ah, ok, I looked at schematics. I basically forgot about DRAM...Agnus had to do the DRAM address translation (+refresh). That does explain it...Still, I think it's a bad compromise. I think it would have been worth it to add DRAM support to eg Gary in order to have cheap fastram...
 
But of course, that's in hindsight. Maybe Commodore thought cheap fastram sideport expansions would flouris?

Not exactly.
As Bloodline said, they had more important thing to care of.
Six months after A1000 debut, CBM was grasping to ensure liquid business since some massive loans were due settling. A massive fraction of revenue came from still actual 8-bit market, while A1000 sales were pretty discouraging, nowhere near the Atari competition. New CEO, Rattigan, cut the costs of perex and opex by splitting platform into 2 separate streamlines. Simpler and cheaper A500 was aimed at market penetration currenttly owned by C64 and A2000 shoot for performance/productivity line claimed by Atari. It would be nice to find some figures how much CBM saved on those A1000vsA500 and A1000vsA2000 ratios, but somehow it worked since just before launch of A500/2000 CBM reported profit.
 
Considering all issues of that specific time, I think that CBM might have done more damage after A1000 debut. They had second chance (1st goes to original Amiga team) with Rattigan, but greedy Gould fired him in split second. Not to mention the awful CBM marketing which blew every damn chance to expand userbase and increase organic market share.
 
IMHO, when we're discoussing what might been wise to do back then, I'll say that CBM might saved it's ass if they went IBM route. Licence chipset, open platform for 3rd party HW assemby and then apply more focus on SW development which would generate enough momentum of detailed concepts and ideas needing better HW. Unfortunatelly, when told about IBM route, those idiots understood only COMPATIBILITY.
 
Ahh...:furious: