Replace the SE/30 ROM with a Custom DuoDock DeclROM, addressing the entire SE/30 MoBo (including its Video Subsystem) as if it were just one, fairly big, relatively ugly (No DuoGray) AIO DuoDock with its pitiable resolution in B&W. The 2300c MoBo would be attached via the Docking Connector (an 030' PDS) at the SE/30's vacated 68030 Socke.t
Bonus Points for using the maxed out Memory banks of the SE/30 as a Silicon Disk for VM to get around the 230c's even smaller 56MB Memory Limit!
I kinda like Eudi's idea more, except the CSC is an off-the-shelf PC VGA chip (Chips and Technologies 65220) so fiddling with the declaration ROM parameters for it to get it to output something the SE/30's monitor is comfortable with would probably be easier than trying to drive the SE/30's video hardware from the 603.
Or try and get your hands on a surplus 9" VGA monitor (there were zillions of them for cheap in the late 90s/early 2000s) and mount that inside the SE/30's case so you can do 640x480.
Now THAT is a very interesting bit of news! I thought CSC was an Apple ASIC. Might SCSC in the 1400 be an off-the -shelf PC VGA chip as well? Mad Dog successfully swapped SCSC into his 2300c back in the day. It sounds like something useful might come of that transplant, given an injection of piggy-backed VRAM.
I just toss these insane notions out there when the pop up out of the murk and sometimes the most incredible information pops up in response.
However, lots of interesting info popped up in the feedback that time as well.
I have a hotlinked list of my hack threads over yonder, should I update it and post it here? Dunno, it might shake a few good bits of info out of the woodwork or I can just let it die over there, but for my own reference.
I've been procrastinating about doing a lookup list for my peripherals threads as well, makes sifting through the sediment easier than the search function every time.
At this point, I'm not aware of any of us having made something that speaks to either a PDS or Nubus slot. It certainly has been something on my mind in the past, and I did wire up a simple card with some AND gates and an EPROM with a valid DeclROM in it, just for kicks. But when I went to try to make a PCB to start doing some simple prototyping, I pretty much lost my mind with trace routing.
Once people start interfacing microcontrollers or whatever to the PDS bus, then I think a lot of possibilities open up. But something like this seems substantially more involved than just a bit of banging on an 030 bus.
Maybe I'll get back around to making another attempt at some point, but it'd be great if someone else jumped at it.
PB1400's ECSC is a Chips and Technologies 62225, also off-the-shelf. (Pretty much all the video in PowerBooks has always been off-the-shelf, the 2400c/3400c use a C&T 65550, and the Kanga PowerBook G3 uses a C&T 65554).
Thanks guys! It's nice to actually get some feedback on my crazy notions. That's been sorely lacking since I had a falling out with a onetime collaborator over yonder. Not that he was all that proficient technically, I'm not either for that matter, but enthusiastic support helps too. EudiG and trag have been great, but it's nice to find another place to hang my hat.
Looks like I'll be reading up on the ECSC/Chips and Technologies 62225 sometime soon. That's a great bit of news, Arbee.
bbraun, I wondered what had become of your PDS Project, it sounded promising. I'm clueless about what needs to be cobbled together to do a project. I always had a partner that did the circuit design, firmware and software, but I got to puzzle out how to layout and fab the boards. I'm pretty darn good at makeshift PCB Layout/Prototyping if you'd like a hand at that end of things, that's the fun part for me.
Outside of that, I like playing with the building blocks in the block diagrams to see what I might be able to shoe-horn into a chink in the armor Apple strapped around the I/O subsystems of RoadApples, LowEndMacs and my mid-range IIsi Plaything.
SMotNC!!!!!! I was hoping that the MiniDock or early DuoDock would have off the shelf C&T controllers. No go on the Docks they have multifunction ASICs from Apple on board.
My noggin' is shut down for the night, so I can't make heads or tails of what's on the MiniDock's logic board, but it ain't from C&T. :P
< fiddles with the DevNotes a bit . . . >
MiniDoc------->VSC - Video, I/O controller with SWIM II
DuoDock----->VSC - Video, I/O controller with SWIM II
DuoDock II --> JET - Video I/O controller, Cache Controller(?) and SWIM II
DuoDock Plus - Can't fine a DevNote, but it appears to be the same as the Duodock II it replaced 10 days before the DD2 was discontinued in '95.. The only differences I see in the spec sheets would be the missing 32k of L2 Cache and the 68882 for the 68030 models. The 2300c couldn't really use either feature AFAIK. I guess they could have used Jet and just left the Cache pads empty.
The easiest part of the PDS card is address decoding, and bus placement.
Hardest part is the bus cycles, and mastering/wait states. Most chips these days speak serial/SPI, or 68XX/8051 bus cycles. Which are simple. Set address lines, Toggle read or write, chip enable, and theres the data. Simple.
With 68K, and other more advanced systems, the bus gets nuts. Tons of wait states, Asyncronous, syncronous, handshake, ACK, multiple control lines per bus cycle, etc.. and you have to have some sort of logic to convert the 68K crazyness to something thats more compatible with modern day chips.