English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware > Hardware mods

 
 
Thread Tools
Old 09 September 2022, 15:55   #41
AJCopland
Registered User

 
Join Date: Sep 2013
Location: Beeston, Nottinghamshire, UK
Posts: 230
Quote:
Originally Posted by alexh View Post
THIS IS an Alice replacement (didn't you read?).
This is an Agnus replacement, it can't drop into an A4000/A1200 can it?
AJCopland is offline  
Old 09 September 2022, 16:08   #42
Promilus
Registered User

 
Join Date: Sep 2013
Location: Poland
Posts: 374
Quote:
1MB, 2MB Agnus and 2MB Alice compatibility
So... sure you can.
Promilus is offline  
Old 09 September 2022, 19:13   #43
kipper2k
Registered User

 
Join Date: Sep 2006
Location: Thunder Bay, Canada
Posts: 4,219
Quote:
Originally Posted by alexh View Post
Because iComp.de is already making a replacement Buster. Ramsey chips are readily available (at least at the moment). THIS IS an Alice replacement (didn't you read?). The Lisa chips are also available, the Lisa functionality has already been converted into as HDL (MiniMig AGA) so could with some re-work become a standalone chip (i.e. not as much re-engineering required).

There are simply no sources of Super DMAC.

It's obvious that you don't have an A3000, but I imagine A3000 owners, or those trying to make Chucky's ReAmiga 3000 would be glad of a source.

Agnus is an 84 pin PLCC so the PCB will fit in any 84 pin PLCC socket (both surface mount and through hole) so the design could be used on any 84 pin PLCC chips. Obvious problem would be the sources available to make it work. It is pretty well down the list, but there is no reason that someone could not do the coding now that the design layout is available for Agnus. If people are willing to support it then it can be done

I am just soldering up Faith (Denise) today so that will join the family

Last edited by kipper2k; 09 September 2022 at 19:27.
kipper2k is offline  
Old 09 September 2022, 21:14   #44
Predseda
Puttymoon inhabitant
Predseda's Avatar
 
Join Date: Mar 2007
Location: Tromaville
Age: 44
Posts: 7,075
Send a message via ICQ to Predseda
You sirs are heroes!
Predseda is offline  
Old 09 September 2022, 21:17   #45
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 39
Posts: 968
So it can be used in cd32 too?

Are all those improvments something like thicking almost "immediate blitter" in winuae?

And one more question. Seriously. Will it work with Vampire if I use it just like an accelerator, no saga and stuff?
Cobe is offline  
Old 09 September 2022, 22:11   #46
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by Predseda View Post
You sirs are heroes!
Not an officer.
nonarkitten is offline  
Old 09 September 2022, 22:24   #47
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by Cobe View Post
So it can be used in cd32 too?
I may have to murder kipper2k for claiming Alice compatibility (as a chip) since the original intent was to be 8372 compatible and offer AGA features. But the on-chip pSRAM broke Amiga 3000 compatibility ANYWAY, so yeah, pie-in-the-sky here, I guess we're making a super-universal Agnus-Alice now. Expect availability in 2032.

Amiga 3000, 1200 and 4000 will only use on-board chip RAM. For Amiga 3000's that means popping out your slow DRAM and sticking in some 70ns FPM memory. I checked, they're plenty available. On these versions, the pSRAM may be omitted since there's no way to open > 2MB on them.

Quote:
Originally Posted by Cobe View Post
Are all those improvments something like thicking almost "immediate blitter" in winuae?
Thicking? Immediate blitter is; as far as I understand, that just queue's blitter jobs and allows the CPU to keep writing. There's limits to how much RAM these FPGA have, so it might not be practical. But the DMA cache allows blitter to act with much LESS CPU interference, so maybe-kinda-sorta?

Even on real chip RAM on the 32-bit machines, opening up 2x and 4x fetch modes for all types of DMA changes everything. Even without "enhancing" anything, just relieving that kind of bottleneck is a big deal. That and having a blitter that's faster than the CPU again would be nice.

Quote:
Originally Posted by Cobe View Post
And one more question. Seriously. Will it work with Vampire if I use it just like an accelerator, no saga and stuff?
Absolutely, why not? There's nothing here that would get in it's way.
nonarkitten is offline  
Old 10 September 2022, 04:14   #48
grelbfarlk
Registered User

 
Join Date: Dec 2015
Location: USA
Posts: 2,591
Quote:
Originally Posted by nonarkitten View Post
I may have to murder kipper2k for claiming Alice compatibility (as a chip) since the original intent was to be 8372 compatible and offer AGA features. But the on-chip pSRAM broke Amiga 3000 compatibility ANYWAY, so yeah, pie-in-the-sky here, I guess we're making a super-universal Agnus-Alice now. Expect availability in 2032.

Amiga 3000, 1200 and 4000 will only use on-board chip RAM. For Amiga 3000's that means popping out your slow DRAM and sticking in some 70ns FPM memory. I checked, they're plenty available. On these versions, the pSRAM may be omitted since there's no way to open > 2MB on them.
Thanks for clearing this up, super exciting!
grelbfarlk is offline  
Old 11 September 2022, 16:14   #49
kipper2k
Registered User

 
Join Date: Sep 2006
Location: Thunder Bay, Canada
Posts: 4,219
Quote:
Originally Posted by nonarkitten View Post
I may have to murder kipper2k for claiming Alice compatibility (as a chip) since the original intent was to be 8372 compatible and offer AGA features. But the on-chip pSRAM broke Amiga 3000 compatibility ANYWAY, so yeah, pie-in-the-sky here, I guess we're making a super-universal Agnus-Alice now. Expect availability in 2032.

OOpsie
kipper2k is offline  
Old 11 September 2022, 18:49   #50
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by kipper2k View Post
OOpsie
In for a penny...
nonarkitten is offline  
Old 14 September 2022, 06:38   #51
hammer
Registered User

 
Join Date: Aug 2020
Location: Australia
Posts: 179
Quote:
Originally Posted by nonarkitten View Post
I may have to murder kipper2k for claiming Alice compatibility (as a chip) since the original intent was to be 8372 compatible and offer AGA features. But the on-chip pSRAM broke Amiga 3000 compatibility ANYWAY, so yeah, pie-in-the-sky here, I guess we're making a super-universal Agnus-Alice now. Expect availability in 2032.
For AGA, Denise needs to be upgraded to Lisa. Denise ECS seems to be incomplete Lisa since Denise ECS lacks Lisa's 8-bit plane support.

Alice's Blitter is still 16-bit like Agnus.
hammer is offline  
Old 15 September 2022, 15:08   #52
Gorf
Registered User

Gorf's Avatar
 
Join Date: May 2017
Location: Munich/Bavaria
Posts: 1,731
Quote:
Originally Posted by nonarkitten View Post
Amiga 3000, 1200 and 4000 will only use on-board chip RAM. For Amiga 3000's that means popping out your slow DRAM and sticking in some 70ns FPM memory. I checked, they're plenty available. On these versions, the pSRAM may be omitted since there's no way to open > 2MB on them.
But you could use the pSRAM as "REU" for ChipRAM:
quickly exchange parts of the on-board ChipRAM.
On the A3000 you could still feed Denise (or replacement) from the pSRAM since it is still only 16Bit.
On all three you could feed Paula this way.

Potential use-cases:
double buffering were the active shown part is in the trans-2MB region, and a quick copy operation every frame from sub2MB to trans2MB...

Or as a WHDload feature to quickly change between game and Workbench, by restoring the wanted ChipRAM contend between one frame...

Or is this a stupid idea?
Gorf is offline  
Old 15 September 2022, 19:19   #53
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by hammer View Post
For AGA, Denise needs to be upgraded to Lisa. Denise ECS seems to be incomplete Lisa since Denise ECS lacks Lisa's 8-bit plane support.

Alice's Blitter is still 16-bit like Agnus.
Thanks for the mansplanation. I wasn't aware.
nonarkitten is offline  
Old 15 September 2022, 19:44   #54
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by Gorf View Post
But you could use the pSRAM as "REU" for ChipRAM:
quickly exchange parts of the on-board ChipRAM.
REU has it's own RAM and DMA's into the 64's RAM. But I think I get where you're going...

Quote:
Originally Posted by Gorf View Post
On the A3000 you could still feed Denise (or replacement) from the pSRAM since it is still only 16Bit.
On all three you could feed Paula this way.
Yes you could, the challenge would be getting the data into pSRAM to begin with.

Quote:
Originally Posted by Gorf View Post
Potential use-cases:
double buffering were the active shown part is in the trans-2MB region, and a quick copy operation every frame from sub2MB to trans2MB...

Or as a WHDload feature to quickly change between game and Workbench, by restoring the wanted ChipRAM contend between one frame...
2MB? Quickly? We can drive the blitter a lot faster but that's still a lot of data. We can't just bank swap, unfortunately.

Quote:
Originally Posted by Gorf View Post
Or is this a stupid idea?
Not a dumb idea; you could still have that spare RAM in Agnus "high memory" and use the blitter to push it to-and-from chip. You could maybe even write directly to pSRAM from the CPU as long as you only write 16-bits to the write addresses. It would be clumsy and not compatible with anything else, but it could work.

So from Agnus point of view we'd have
Code:
$000000-$1FFFFF 2MB Base Chip RAM (in both 68K and chip space)
$200000-$7FFFFF 6MB Extended Chip RAM (like UAE, only with new Gary)
$800000-$FFFFFF 8MB Expansion Chip RAM (available via DMA only)
32-bit CPUs would only have Expansion Chip without a new Fat Gary or Gayle and the Base Chip RAM would still use motherboard RAM. Fat Gary or Gayle would be 'hacked' to force 16-bit mode for chip (essentially disabling the MUX) and then could open up all 16MB.

ECS machines would have the 2MB Base Chip RAM and indirect access to the Expansion RAM. But like the 32-bit machines, Extended Chip RAM would need a modded Gary (much easier than a modded Fat Gary though).

But all of custom chips can use the Expansion Chip RAM and we could extend the libraries to allow that. So like you said, WB could have its entire display in Expansion Chip RAM and not use one byte from the 2MB Base Chip RAM for games that can't see that. It would still need DMA, so it's not "free" like RTG would be, but it's close!

This would also be trivial to add to UAE. Maybe we can ask Toni to mock up our "16MB Expanded Chip RAM Mode."
nonarkitten is offline  
Old 15 September 2022, 20:42   #55
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
I just realized that this also partially works with OCS (Amiga 1000). It would essentially work like this. And technically anything the CPU cant reach is Expansion RAM. It's not a perfect fix for the 1000, but it could be a big improvement from its stock 512KB. Does mean putting an pSRAM chip on Skinny Willoe thought...

Amiga 1000:
Code:
$000000-$07FFFF 512KB Base Chip RAM (CPU+Chip)
$080000-$FFFFFF 15.5MB Expansion Chip RAM (Chip Only)
Stock Amiga 500/2000:
Code:
$000000-$0FFFFF 1MB Base Chip RAM (CPU+Chip)
$100000-$FFFFFF 15MB Expansion Chip RAM (Chip Only)
Stock Amiga 500+/600:
Code:
$000000-$1FFFFF 2MB Base Chip RAM (CPU+Chip)
$100000-$FFFFFF 14MB Expansion Chip RAM (Chip Only)
Amiga 500/2000/500+ with Xander
Code:
$000000-$1FFFFF 2MB Base Chip RAM (CPU+Chip)
$200000-$7FFFFF 6MB Extended Chip RAM (Opt. CPU+Chip)
$800000-$FFFFFF 8MB Expansion Chip RAM (Chip Only)
Stock Amiga 3000/1200/4000
Code:
$000000-$1FFFFF 2MB Base Chip RAM (Motherboard, CPU+Chip)
$200000-$FFFFFF 14MB Expansion Chip RAM (Chip Only)
This means all pointers for DMA are 24-bit. Just have to remember that the extended 8MB in chip is NOT the same 8MB that the CPU can see (which would be full of things like registers, ROM, Ranger RAM, etc.)
Code:
xxxxPTH High 9-bits of address
xxxxPTL Low 15-bits of address
nonarkitten is offline  
Old 16 September 2022, 10:02   #56
Gorf
Registered User

Gorf's Avatar
 
Join Date: May 2017
Location: Munich/Bavaria
Posts: 1,731
Quote:
Originally Posted by nonarkitten View Post
32-bit CPUs would only have Expansion Chip without a new Fat Gary or Gayle and the Base Chip RAM would still use motherboard RAM. Fat Gary or Gayle would be 'hacked' to force 16-bit mode for chip (essentially disabling the MUX) and then could open up all 16MB.
With 70ns FPM on board double CAS should be possible for these operations, meaning Gary would take 32-bit from/to CPU and make two consecutive 16-bit writes/reads on ChipRam... no?
Gorf is offline  
Old 16 September 2022, 15:20   #57
NorthWay
Registered User
 
Join Date: May 2013
Location: Grimstad / Norway
Posts: 769
So riddle me this; I thought the OCS/ECS chip memory was 16 bits wide at 280ns, so is AGA really slower than 140ns to need to use double-CAS? Shouldn't there be time to simply do two accesses in 280ns?
And to follow on from that: Shouldn't AGA be able to practically do quad-CAS in 280ns?
NorthWay is offline  
Old 16 September 2022, 16:41   #58
nonarkitten
Registered User

nonarkitten's Avatar
 
Join Date: Jun 2018
Location: Calgary/Canada
Posts: 229
Quote:
Originally Posted by Gorf View Post
With 70ns FPM on board double CAS should be possible for these operations, meaning Gary would take 32-bit from/to CPU and make two consecutive 16-bit writes/reads on ChipRam... no?
If Gary is altered to signal that chip RAM is 16-bit then I'm not sure if the MUXes will work right. Might need to check. If it can work then the 3000 would have as slow access to chip as all other ECS machines.

Yes, with 70ns RAM, burst mode might have been available, but I'm pretty sure Gary lacks the signalling to the CPU to make that work. 70ns RAM might (just) fast enough to theoretically squeeze in two regular read operations (120ns) in the Agnus allocated interleave but that's pushing it. But may be possible. I think there's timing on top of that 120ns on the CPU side that might blow over the 140ns budget without a really fast 030.
nonarkitten is offline  
Old 16 September 2022, 16:58   #59
roondar
Registered User

 
Join Date: Jul 2015
Location: The Netherlands
Posts: 3,269
Quote:
Originally Posted by NorthWay View Post
So riddle me this; I thought the OCS/ECS chip memory was 16 bits wide at 280ns, so is AGA really slower than 140ns to need to use double-CAS? Shouldn't there be time to simply do two accesses in 280ns?
And to follow on from that: Shouldn't AGA be able to practically do quad-CAS in 280ns?
I'm not a hardware expert and as such I'm sure nonarkitten can give a better answer, but I always thought that the Amiga chipset internally is still 16 bits even on AGA and that's why it needs to use these kind of double modes to achieve the 32/64 bit fetches.

However, take this answer with a grain of salt until someone who knows for sure verifies it (or debunks it)

Edit: loving the all HW details in this thread by the way, helps me understand some things better
roondar is offline  
Old 16 September 2022, 18:30   #60
Promilus
Registered User

 
Join Date: Sep 2013
Location: Poland
Posts: 374
@roondar - nope. AGA is 32b chipset EXCEPT blitter which is inside Alice and still 16bit wide (just like Alice memory interface). That's also a reason why with even slightly improved A1200 blitter itself was becoming obsolete as it was pretty hard to use it efficiently in conjunction with fast, fully 32b CPU. It was just easier to leave it out and save those DMA slots. As the blitter was a workhorse for OCS/ECS effects and amazing performance and was in decline in AGA it just meant good ideas by using "co-processors" in chipset were running out at that time.
Promilus is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Amiga 500 and Agnus cleaning without removing Agnus? turrican9 support.Hardware 16 26 January 2016 17:05
Universal Translator mritter0 request.Apps 2 14 June 2014 20:28
Universal Warrior Asle HOL data problems 4 10 September 2011 23:14
swap fat agnus with agnus extralife support.Hardware 12 23 July 2008 16:35

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 00:42.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.
Page generated in 0.10719 seconds with 14 queries