ECS Agnus / Full ECS ChipSets....

This is a doubt i have, what are the differences in WinUAE when i chose one of this chipsets ECS Agnus or Full ECS they are both ECS right, what's the difference and for what situations?

Thanks,
Chapas

[LocalH]

ECS Agnus only emulates the ECS Agnus. Full ECS also emulates the Super Denise as well.

I've not used the ECS Agnus setting (other than it being forced if you use 1MB of chip RAM or more, since the OCS Agnus only supported 512K chip). I either use full OCS or full ECS, depending on the software.

Simple.... ...i tought that only Agnus was changed. So ECS has 2 versions in real life? Or just in the emulator?

Thanks again,
Chapas

[LocalH]

No, 'chipset' in this context actually deals with two chips - Agnus and Denise (Paula is pretty much the same across all chipsets, named Portia on the A1000, but otherwise the same AFAIK). Both chips have an ECS and OCS version, and you should be able to intermix. I used to run an Amiga 2000 with an ECS Agnus (1MB chip RAM) and OCS Denise. Also, to get the 1.0 and 2.0 Video Toasters to work with the A3000, you must mod the case (to get the board to fit) and replace the ECS Denise with an OCS Denise (but, obviously, you leave the ECS Agnus in so that you have all of the A3000's standard 1MB chip RAM). The only setup that I can think of that isn't currently emulated would be the early A1000's without halfbrite (but I can't think of any software that relies on halfbrite not being present, so it's not really that useful for anything other than emulation completeness).

For emulation, I've found that I don't really use the ECS Agnus setting much (mostly in an automatic fashion if I choose an OCS config then up the chip RAM to 1MB). I either use OCS with OCS software, or ECS with ECS-aware software (which, admittedly, isn't too often).

[alexh]

Dont forget that there was the SuperFat Agnus in the A600 & A500+ (2mb chip) and they were ECS machines.

[LocalH]

Well, right. And also the 2MB chip RAM upgrades for A500/A2000. But still, those would also be considered ECS Agnus chips, and I think would be handled in the same way by WinUAE. As far as I know, the only important difference between the 1MB and 2MB Agnus is just that - the chip RAM.

Just a little side note, the later Amiga 500s were shipped with ECS Agnus only...(I dunna know, are these the Amiga 500+s???)

Anyways, my Amiga 500 has an ECS Agnus and AGES ago, there was some method to allow the A501 512K expansion appear as additional chip memory. You had to cut a trace or something...can't quite remember. I did do that to my Amiga 500 to get the 1 MB of chip ram.

Jason

[LocalH]

You were essentially doing the same thing that you do on the A2000 to turn the built-in 512k fake fast into chip RAM, with an upgraded Agnus (because when I upgraded my old one, I remember cutting a jumper to make the whole onboard RAM appear as chip). As far as I know, the trapdoor expansion and the A2000 fake fast are identical as far as the system is concerned.