English Amiga Board


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

 
 
Thread Tools
Old 22 December 2020, 18:41   #1
eXeler0
Registered User

eXeler0's Avatar
 
Join Date: Feb 2015
Location: Sweden
Age: 47
Posts: 1,935
Hacking the Blitter & Copper with FPGA Alice

Howdy,

Ran across this old post on the FPGA Arcade forum...
https://www.fpgaarcade.com/punbb/viewtopic.php?id=1325

... and it got me wondering if there ever was an attempt made to improve the Copper and the Blitter by placing an FPGA implementation of Alice on top of the chip itself on the motherboard (although, it sits in a bad spot near the tight edge under the keyboard).
I'm thinking something similar to Indivision but that sits on top of Alice instead..

Just for fun, would it even make sense to try to fix Alice to something more like the AA+ spec with 32bit Blitter/Copper.. etc? AFAIK AA+ would have been largely backward compatible with AGA..
eXeler0 is offline  
Old 23 December 2020, 14:58   #2
hooverphonique
ex. demoscener "Bigmama"

 
Join Date: Jun 2012
Location: Fyn / Denmark
Posts: 1,229
This is not really possible as Agnus interacts with the rest of the system, and a piggyback would need to aswell, thus creating a conflict - the indivision just "listens" to the data being picked up by Lisa, thus not interfering with anything.
hooverphonique is offline  
Old 24 December 2020, 15:01   #3
pandy71
Registered User
 
Join Date: Jun 2010
Location: PL
Posts: 1,731
You can do anything with FPGA but what with software? You can for example place local RAM for Copperlist and thus eliminate some of the limitations, you can internally work with higher clock efficiently do all in single cycle, more important is that RGA bus is physically same on all Amiga's so technically A1000 = A4000 - all improvements are inside silicon hooked to this bus... Also some RGA instances are not used so it can be used for extending chipset capabilities - this is used by Indivision i believe (using two address location efficiently you could made extension up to 65536 16/32 bit registers), finally you can improve RGA by increasing clock and or modifying its concept to high speed multi-point link. From technical perspective not an issue but once again question is who will wrote software using all this?
pandy71 is offline  
Old 25 December 2020, 02:00   #4
eXeler0
Registered User

eXeler0's Avatar
 
Join Date: Feb 2015
Location: Sweden
Age: 47
Posts: 1,935
Quote:
Originally Posted by pandy71 View Post
You can do anything with FPGA but what with software? You can for example place local RAM for Copperlist and thus eliminate some of the limitations, you can internally work with higher clock efficiently do all in single cycle, more important is that RGA bus is physically same on all Amiga's so technically A1000 = A4000 - all improvements are inside silicon hooked to this bus... Also some RGA instances are not used so it can be used for extending chipset capabilities - this is used by Indivision i believe (using two address location efficiently you could made extension up to 65536 16/32 bit registers), finally you can improve RGA by increasing clock and or modifying its concept to high speed multi-point link. From technical perspective not an issue but once again question is who will wrote software using all this?
Howdy,
regarding the software, depends on how its done, I guess. Maybe if it was done, it would be worth looking at how SAGA in Vampire "extended" the Blitter / Copper without breaking backward compatibility. Then the answer is, software written for Vamp could run better on regular Amiga with enhanced copper /Blitter, buuuut maybe I'm just dreaming here ;-)
eXeler0 is offline  
Old 25 December 2020, 02:41   #5
IanP
Registered User

 
Join Date: Mar 2015
Location: Bristol/UK
Posts: 161
I'd forgotten that an attempt was made to decap and reverse engineer Alice. I downloaded what appear to be original commodore Alice schematics recently I think I got them from another FPGA github project.
---edit---
I wont link to them but if anybody wants them they are in the Agnus directory of the Amiga replacement project of nonarkitten on github

Last edited by IanP; 25 December 2020 at 02:46.
IanP 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
2X2 C2P Via copper and blitter line sandruzzo Coders. Asm / Hardware 4 10 October 2020 23:15
Driving blitter from copper ebenupton Coders. Asm / Hardware 30 21 October 2019 18:36
Immediate Blitter & Wait for Blitter... volvo_0ne support.WinUAE 29 10 December 2018 17:56
Avoiding copper strobe/blitter bug mc6809e Coders. Asm / Hardware 31 28 November 2013 08:09
Blitter using the copper... h0ffman Coders. Asm / Hardware 9 23 February 2012 08:25

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 14:12.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Page generated in 0.06981 seconds with 13 queries