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68030 accelerator for the Macintosh Portable, redux.

Trash80toHP_Mini

Trash80toHP_Mini

NIGHT STALKER
68040
I've been resurrecting some projects from the past, this one is about four years old. Currently working on a five year old project, but ran across these pics and thought to toss it out there for brainstorming.
PerformerLaguna-0001-AI9.jpg


This one includes the Portable HDD replacement converter I cooked up even earlier.


MegaKluge-000.jpg@Bolle and I were working on getting my Performer SE/Plus/Classic Accelerator clone and I was off on the crazy notion that it might run at 32MHz when fed the C16MHz reference clock available on the SE PDS. He gave it a shot, but timings didn't work out.

I'd figured that power to run an adapted SE Accelerator in the Portable would be harvested from a takeoff on the 12V rail available on the HDD connector. stepped down via Buck Converter. Dunno, at the time I'd figured the 5V rail would be more limited and SCSI2SD replacement of the HDD.

Haven't found the AI files yet, but just came across the pics. ISTR seeing that more complex SE Accelerators have been worked out, so it's time to take a look with a fresh eyes in the sockets of skulls more technically competent than what little remains functional between my own, very old ears. 🤪

So, whatcha thinkin' gang?
 
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Techknight would be the best person to speak to on Mac Portable stuff... He's well versed in all Mac Portable for sure.
 
I think we've got a couple of 68000 -> 68030 accelerators in the can at this point?

A long time ago, in musings far and gone I got it into my head that the Portable PDS Card could be a simple riser that the accelerator would plug into it from the HDD bay. Back then it was a 2.5" HDD replacement's reduction in power and cubic paving the way for acceleration.

The advent of SCSI-to-Whatever frees up even more power and cubic, so stacking on a memory daughtercard for ye olde SE VM expansion pops right into my noggin. ;)
 
LaPorta said:
I'm still waiting to hear back from the guy working on the Portable 100 modem slot WiFi adapter made in the form of a card for the Portable.

Announcing and interest check: Integrated AirTalk for PowerBook 100 series

You know, I am very sorry that this slipped past me. I’ll measure the dimensions this evening. Please do send over your illustration.
68kmla.org 68kmla.org
Click to expand...
That's me :D Unfortunately life caught up with me and I didn't have a moment to touch any mac related stuff, I did make a preliminary drawing of the board!

I'm curious about the accelerator too. Would it include roms? I was looking at the processor slot in the PB100 and it has the same signals as the PDS slot of the SE, the main difference is that the daughter board contains processor and roms, so a new accelerator must come with it's own set. And the SE also boots with the 60000 and then switches to the '030 right?
 
Me too, life happens, glad you have time for posting again.

twelvetone12 said:
I'm curious about the accelerator too. Would it include roms? I was looking at the processor slot in the PB100 and it has the same signals as the PDS slot of the SE, the main difference is that the daughter board contains processor and roms, so a new accelerator must come with it's own set
Click to expand...
Th e PB100 CPU card has RAM on board, ROMs are the main board, no? Was looking into doing a miniaturized Performa for the PB100 at the same time as the Luggable.

twelvetone12 said:
. . . the SE also boots with the 60000 and then switches to the '030 right?
Click to expand...
Pretty sure that's right, but ISTR the Plus might boot to the Performer without the presence of the 68000?

As I see it, noodling out in general how SE accelerators translate from 68000 bus/PDS to 030 bus would be the first step. 68K PowerBooks of all stripes/CPUs run on a slow 68030 I/O bus (backside?) directly or bridged by Pratt in the Blackbirds. Not so familiar with the BlackBirds and the PB190. PBX bus bridge in the case of 603e 'Books is more my thing.

First steps first, but I've got a thing for impossible dreams, the wildest of which would be taking the next. Interfacing the 68000 bus to 68030 with 68040 or 603e bus bridge ASIC would be the coolest of things.****


*** That teaser would be about getting the SE/30 maniacs involved. They've already got 68040 accelerators on hand.

Crazier yet would be getting the 68000 bus interfacing with the Pratt bus bridge ASIC of the Blackbirds. Craziest notion of all would be getting from 68000 bus to the PBX bus ASIC bridge of the PB1400. In either case ROMs and RAM are on the CPU (front side?) bus.

Either approach might be opening the Portable up to existing processor cards and accelerators for Blackbirds/1400.

Blackbird PPC conversion CPU cards make the jump to PBX off their slow side 68030 bus. Portable/G3/64MB anyone? LOL! 🤪
 
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I wonder if it would just be better to put the RAM and ROM on the accelerator card, and ignore the original processor entirely, that way the RAM isn't limited and you don't have to worry about the processor switchover.
 
That's exactly what getting the Portable/SE PDS to interface with Pratt or PBX memory controller ASICs would do, but that's a particularly crazy notion.

Mimicking an SE Accelerator for the Portable is a tall enough order for now.
 
You wouldn't need any sort of advanced memory controller, a simple CPLD would suffice. With the processor, RAM, and ROM on the card, the only time you need to access PDS is to access I/O, display, etc.
 
Got it, but you're talking about designing a new accelerator, no? My point has always been to employ existing designs/drivers.

If you can get the known formulas of the GALs on the top green Performer/Portable board twerked into the CPLD on the bottom green board we've a great start. They need to play nicely with the 16MHz bus of the Portable, doubling "Performer's" CPU clock to 32MHz.

SuperSVGA said:
. . . the only time you need to access PDS is to access I/O, display, etc.
Click to expand...
Exactly. Once the Portable interacts as such with the 68030 socket, things like PowerCache step to the forefront?

Forgot to mention that the fallback pl;an (main line of development for anything more hungry than the Performer) is to power the Accelerator from an external source when it's plugged into a jack in the modem port.. When not plugged in it automagically reverts to standard Portable mode for on the road use.

Did the Portable fit on the Airline Trays of its era? :ROFLMAO:
 
The biggest issue will be that you will need to patch a good bit of the Performer's control panel, as it applies ROM patches and also expects the memory map of the Plus/SE/Classic.
 
Same, haha. Would be awesome to run 7.5.5 on my Macintosh Portable w/ the backlight. Would 100% pay a pretty penny for this! Don't have much knoweldge regarding circuit design, but hopefully someone can make this! The Mac Portable is so underated!
 
Good news/bad news situation. @Bolle has read the GALs off my Performer and cloned it. Timings don't work out for running it at 32MHz from the Portable's clock though. But 68030 is hella better than 68000 on a 16MHz clock, especially in terms of software compatibility. Dunno about extended OS capability?

SE PDS cards run in an expansion chassis for the Portable, whose PDS is ostensibly the same as the SE PDS. I'm not lookin' as I'm a bit burned out with other projects ATM. If one of you guys want to take a look at the Luggable/SE PDS address ranges, finding them identical could be a big step forward I'd think?
 
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Interesting, was really just noting how the 68000 isn't great for 7.5.5, even though it technically can run it. Not to advanced at these sort of things, so not sure how I would help, but will definitely be monitoring and chiming in when needed.
 
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