nonarkitten / amiga_replacement_project Goto Github PK

super cool that we got the OCS Agnus schematics signed by jay miner and joe decuir.

https://github.com/nonarkitten/amiga_replacement_project/blob/master/agnus/MOS_Agnus_compressed.pdf

Is there any chance that someone has also some drawings for ECS agnus too? Maybe somewhere in the attic …

or maybe some old document which shows the differences ?

@hazydave do you possibly have an idea who we can ask about old dusty ECS schematic drawings?

I've seen die shots, that suggest, that in a real paula those outputs are open drain. If they where push-pull, the ususal NMI switch (pulling IPL2-IPL0 straight to GND) could kill the IC.

Therefore only 0 or Z should be assigned to ipl_n in Paula.v

Need to add the transparency bit in the colour look up tables.

I noticed a service manual was recently uploaded. So I am asking what's exactly the scope/extent of the project, if it can span over schematics/service manuals of all the amiga models or there's a limit. For example, I just found this folder which contains a lot of material which might be preserved here, if the material gets organized properly.

Hi,

Maybe I'm not looking in the correct place but can it be that I'm missing the schematics for rev0.5 board?
I see a it jumps from rev 0.4 to rev 0.7.

The original Denise code did not read the mouse quadrature. On the Amiga this is multiplexed on the CCK signal and should be read on the CCKQ edge. This has been implemented and completely untested as of yet.

Remove PLL and rely on stock clocks. The original Denise chip has only two clock inputs: 7M and CCK. From this, it's possible to drive a 14MHz event on the positive and negative edges and also generate CCKQ from the XOR of 7M and CCK.

ECS Denise adds the CDAC (quadrature 7M) which allows the creation of a 14MHz clock and 28MHz events which would be required for super hires and productivity (pseudo VGA) modes. I say pseudo here only because VGA is normally 25MHz, not 28MHz.

I'm curious. I know the chances of this are slim and the architecture of the Amiga 1000 is unique in some sense (it's the only OCS model without a Gary), but is there even the slightest possibility of making ReAgnus (Willoe) work with an Amiga 1000, unlocking 2MB of ChipMem?

I found this project earlier, so the form factor shouldn't be the main concern

https://github.com/LinuxJedi/A500-2Meg-Chip-ram