raffles wrote: ↑Mon Nov 25, 2019 1:46 pm
Yeah, _VPA and _BR @DIP64 are pulled high through a 1 kohm resistor, and _BR (and indirectly _VPA, as they are tied together on the A600 mainboard) on the PLCC socket are pulled low through a 220 ohm resistor). I think you are correct in that Stephen thought that messing with _BGACK could be a solution. I haven't messed with this anymore, as noone (as in the 3-4-5-ish people that's got the adapter) has been able to get the TF534 working reliably, while both the TF536 and Matzes 030 accelerator showed great promises. I was holding off until the 536 release before diving deeper, but when that got canned I kind of zoned out.
I've been thinking about making a pure A600 accelerator from Matzes designs, but I haven't started yet. And I don't know if I ever will
I have the eagle files published on my gitlab page for a straight adapter with the footprint for the upside-down PLCC connector if you need something to base your design on. Or are you done with that part? I think it would be awesome if you could make it work!
(I think I'm kinda close to 100 % sure of the pull-ups/pull-downs mentioned above. I looked through a couple of images to check it out, but I could have gotten something mixed up.)