Radius Full Page Display for Macintosh 512ke/Plus - Cloning project possibilities?

Trash80toG4

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Apr 1, 2022
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FPD/SE bits are beginning to come together. Ordered up male and female header interconnect parts today for more experimentation. Here's what I've played around with so far:

Performer-BlackMagicalBus-01.JPG
First set of single inline sockets arrived from China. They don't mesh onto the Radius FPD connector's headers, which appear to be about the same thickness as .1" pitch headers, but .05" pitch so pins don't insert. I was able to sand the socket housing's face down. That removes the plastic surround so I can get a really snug, electrically solid fit. Second connector is on it to protect the soldertails.

Performer-BlackMagicalBus-02.JPG
Hopefully the parts on the way will be what I need, but at least I've a proven modification. With a bit of sanding of the interstitial connector added, the kluge and some hot glue the FPD and TPD cards for the SE, with a new printed bracket for adjusting the height differential, will be compatible with the setup proposed below:

Performer-BlackMagicalBus-00.JPG

BlackMagicalBus is what I call the crazy contraption illustrated by the board sandwich above. It's a mating of an elongated board for the MicroMac Performer Clone project I started @Bolle pulled off so masterfully when I sent him my board. with as close to as I can come up with as a replacement for Radius' MagicBusconnector for their SE Cards using available parts.

I haven't got a Plus board handy, but the hope is that the FPD/Plus board can be cloned and placed vertically on a slightly offset variant of the elongated Performer/BlackMagicalBus Accelerator. The chassis opening of the Plus looks like it will make such a bodge possible.

A direct 1:1 clone of the FPD/Plus is one thing, but getting it to play nicely with the Performer is another thing entirely. That's the dream I have for the Drexel Plus in which I found the Performer.
 
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Trash80toG4

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Once the connector setup is worked out, with or without backward compatibility with the Radius cards, it's on to the next step.

Scanline-Rotation-00.JPG


As proposed upthread: rotation of the image appears to be the most serious obstacle, but my concept for column stripping of the frame buffer appears to be as simple ad is gets.

The first approach Nick Gillard looked at for his Pico-Mac-Nano would appear to be the same as the diagram above? He abandoned it and went with a compromised approach to using a portion of his native 480x640 "Portrait" format LCD which did an end run around the rotation problem and made for a much smaller Mac replica.

Using the same Pi Nano on the clone would take care of rotation. but killing two birds with one stone seems the thing to do:

Pico Nano-IMG_1871-1024x768.jpeg

1) not having to emulate the Mac, his Nano would have had plenty of power to do the rotation
2) Pi Zero/Zero W however, has Mini HDMI output right there on board
3) Mini HDMI is perfect for a custom panel display and adaptable to DVI-D for using 19" range, obsolescent, pre-HDMI Displays.

Question: where might be the best place to capture the frame buffer? Readout from VRAM buffer or thw Zero itself acting as VRAM buffer? If not enough GPIO on the Zero to strip the columnar data from the captured Frame Buffer in VRAM it could be captured from the interface cable pins.

But I imagine there's a way to channel the FPD's VRAM buffer through the Zero's GPIO lines? In that case it might replace the VRAM frame buffer entirely, rotate image and spit it directly our its Mini HDMI port?

Scaling would be the next bugaboo, if and when. But that's for another day, my 1024x768 panel arrived today! :D
 
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Trash80toG4

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That's almost certainly a precursor to the Killy Klip?

- so why on Earth is there a second 68000 in the mix?
- Plenty of ROM on there to use it as a CPU?
- No dedicated RAM as on the Atto Silicon Express II?
- Is there enough VRAM on the card to be shared with the 68000 along with Frame Buffer tasking?
- might VRAM be addressed by 68000 on the card between buffer cycles?

68000/ROM/RAM setup on ATTO SiliconExpress II

ATTO SiliconExpress II.JPG

Way too many questions ATM.