AGA requires quadroupling the data rate, which is pretty much impossible on 2-layer boards without a wider data bus.
AGA reaches twice the data rate with a twice-as-wide data bus and another factor of two with double-CAS accesses (kind of a burst). This would have to be translated into a burst of 4 16-bit words in order to get the data across from the Agnug socket to the Denise socket.
Given the short data-valid-window and the extremely flaky rise/fall times of the chip data bus, such a transfer would be very flaky, if not impossible. It all comes down to making a new mainboard.
In my opinion, you don't really need AGA in everyday life. My A3000 was my favourite Amiga for quite a long time, mainly due to it's compactness and the built-in flickerfixer. I guess this place will be taken by an A500 or A600 now, as it can run without any moving parts (CF card instead of HD, fanless power supply).
Jens
I agree Jens, AGA is not really needed, but I understand the desire of many who always wanted to be able to get AGA working for their A500, A600, A2000 and A3000 Amigas. Some would even want it for their CDTV and A1000's. It all goes back to the old Amiga way of doing more with less and keeping old gear working for years and years past any reasonable time it should have been used. I have plenty of AGA Amigas, so I don't have such a desire to make my ECS Amigas able to run AGA games and programs. Your IndivisionECS is all the display enhancement I need or want for an A500 & A600 and my big box Amigas all have graphic cards in them.
Thanks again for creating all the great Amiga gear you have produced. Keep on providing us Amiga fans with new ways to enjoy our hobby.
Any chance that you will complete an 030 accelerator for the A600 that will work with the A603 and IndivisionECS? That would really get the A600 close to being a replacement for the A3000 you mentioned. Specially if it could be fitted with a USB controller to connect an external CDRW drive.
Edit: NovaCoder, I think that NatAmi, or an add-on for Jens own C-One computer would be better suited for duplicating and hopefully improving upon the AGA chipset than trying to squeeze it into 2 IndivisionECS boards. I think the dream of having AGA on any of the old ECS or OCS Amiga models is just that, a Dream or a Fantasy.