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#1 2014-09-03 17:22:25

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,469

SE/3000

Thanks to a craigslisting typo in CC's linkage, I'm really having trouble resisting the pull of SE/30 upgrade fanaticism, something I've never before understood  .  .  . ****

.  .  .  whatever  .  .  .  hmm

Here's the (customarily insane roll ) hack proposal:

Install a 32bit Clean Custom ROM to lie like hell to the CPU ( I never said I had anywhere near the chops to pull this off, did I? )

Replace thru-hole 68030 with Socket

Eschewing the usual PowerCache install at this point, install a fairly complex custom PCB

PCB Development specs/requirements:

SMT rework removal the PBX PPC/68030 slow side bus bridge/buffer ASIC from just about any NuBus Architecture PPC PB (1400 preferred)

Broiler Oven installation of same to custom PCB

SMT rework removal the CPU connectors from a DOA (or borken lid) PB1400 MoBo

Broiler Oven installation of same to custom PCB

SoNNeT_SIMPLY FAST



WAG: The 1400 ROM might need to be added to the FSB side of the PCB, dunno, as noted, it's just a guess.





**** I find this especially galling because I've worked out the details for my SuperIIsiHack™ to kick the @$$ of any maxed out SE/30 running 6.0.8 thru 7.1P for cripes sake!

Last edited by jt (2014-09-03 17:32:06)

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#2 2014-09-03 20:10:56

MinerAl
Member
From: The not-so-great plains
Registered: 2014-08-26
Posts: 73

Re: SE/3000

Might be easier to use a Q605 board+upgrade.  All you'd have to do is figure out how to get the video working...

wink

Last edited by MinerAl (2014-09-03 20:11:34)

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#3 2014-09-04 00:21:02

Mk.558
Member
Registered: 2014-07-08
Posts: 168

Re: SE/3000

Or to make your own SE/30 Turbo 040 adapter.


SE/30 Cap Replacement http://tinyurl.com/mjf24zs
Classic Mac Networking v3.1 http://applefool.com/se30/
"Linux assumes you know exactly what you are doing." -oboedad55, ubuntuforums.org

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#4 2014-09-04 00:21:02

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,469

Re: SE/3000

But that would only be and SE/30/040!

PPC or bust! tongue

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#5 2014-09-04 15:53:16

Eudimorphodon
Member
Registered: 2014-09-02
Posts: 525

Re: SE/3000

As usual I suppose I have to admire the audacity of the proposal here, if nothing else. Just looking at the block diagrams in the Duo 2300 technical note the first objections that come to mind from me:

The PBX IC includes a RAM controller and a private bus for both system RAM and ROM; presumably it has some internal logic which decides whether a bus request is going to be routed to its private bus or through the "030 bridge". (It in fact *must* have that capability, because otherwise it would have to send *every* bus request through the bridge "just in case" there were a peripheral/RAM mapped at any given address, and doing so would thus mean that the private bus wouldn't be able to run any faster than the bridged one; I'd be willing to bet a shiney new nickel that it only maps accesses to the "slot/peripheral" areas to the other side.) There's actually a reference in the tech note to a register file in the chip that's used for mapping blocks of RAM into contiguous chunks, and... although it doesn't come out and say it I suspect that the chip also directly generates signals like the output enables for the ROM and RAM based on internal address decoding. In other words, I sincerely doubt that this IC would be suitable for use as the basis for a CPU-socket-based upgrade to an existing system unless:

A: You're willing to have your CPU upgrade board also host all the system RAM and ROM; onboard RAM sockets are off limits. (Therefore also leaving you stuck with the 64MB max RAM limitation of the PBX.)

B: Everything else you might possibly need to access on the host motherboard is addressable (or can be made addressable) within the bridged space passed through the PBX.

C: Obviously you'll need a custom version of the PowerBook/Duo's ROM which replaces all the drivers for the PowerBook's onboard peripherals (Whitney/Combo/Singer/CSC/etc.) with drivers for the Mac II family peripherals you'd find in a thing like an SE/30. I seriously doubt they're just "in there".

*Perhaps* A: (and to a lesser extent B:) isn't set in stone if the PBX secretly has some programmable registers that would let you adjust what memory areas are "punched through" to the slow side; I wouldn't completely rule out there being some magic bit you can twiddle that'd let you ignore the private RAM bus and map through to the motherboard socket space, but, again, C: is completely inescable. (And if you *could* do it you'd obviously need to completely rewrite the power-on/reset hardware initialization sequences.)

Seems to me if you're really going to this level of effort to reuse these (undocumented/unavailable) PowerBook ICs you might as well go all the way and design a replacement motherboard around the architecture; just use everything in the original Duo design except for the CSC; for that substitute a simple CRT controller that can drive the SE/30's monitor directly and swap out that one driver in the ROM. You could probably do a Mac SE/30 video controller with a single big CPLD, a small static RAM chip, and a few bits of analog glue; that's way less reverse engineering than what you're proposing as the rest of the motherboard trace routing could be pretty much copied verbatim from the original PowerBook design.


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#6 2014-09-07 19:41:00

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,469

Re: SE/3000

As usual, thanks for being the voice of reason Yin balancing my off the wall YangFu. As for this first set of objections:

Actually, my second thought was to 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 AIO DuoDock with its pitiable resolution in B&W. The 2300c MoBo would be attached at the Docking Connector (O30' PDS)/68030 Socket intersection.

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!

Don't forget the swing out portrait LCD! big_smile

Last edited by jt (2014-09-07 19:43:35)

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#7 2014-09-09 16:50:57

Eudimorphodon
Member
Registered: 2014-09-02
Posts: 525

Re: SE/3000

jt wrote:

Actually, my second thought was to 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 AIO DuoDock with its pitiable resolution in B&W. The 2300c MoBo would be attached at the Docking Connector (O30' PDS)/68030 Socket intersection.

There's no way I'm spending the time necessary to dig through the necessary reference material, but from what I remember it *may* actually be within the realm of possibility to design a PDS card for the SE/30's PDS slot that when activated would put the CPU to sleep and allow another machine to access the onboard peripherals on its own terms. (I'm *pretty sure* the slot has the capability to support a bus-mastering device; it'd pretty much have to in order to support CPU upgrades.) Such a card wouldn't exactly be trivial to design but these days it'd probably be possible to implement it with just a few CPLDs or an FPGA.

Of course, since it's 2014 why bother designing a bus bridge to make it act like a DuoDock? (In the grand scheme of things it's not like a Duo is really any more useful than an SE/30.) For the heart of the card you might as well use one of those ASICs that's an FPGA plus an ARM CPU and set it up so once the SE/30's initialized the hardware it puts the CPU to sleep and presents all the internal peripherals (framebuffer, SWIM chip and attached drive, SCSI port, etc.) as USB 2.0 bus targets. IE, any drives attached to the SCSI connector will be presented as USB Mass Storage devices, the floppy drive as a USB floppy drive... but a *special* one that supports the Mac 400/800k formats, and the framebuffer as something similar to those toy monochrome LCD graphics displays. Heck, also include USB HID support for the SE/30's ADB keyboard and mouse. Then you could trivially hook your Zombie SE/30 up to any modern computer and use a slightly modified version of BasiliskII or Sheepshaver to emulate a *ridonkulously* fast Classic Mac while also letting you use the SE/30's keyboard and mouse with your modern software. (IE, set the SE/30 next to your "real" computer's monitor and set up a keystroke combination that would switch keyboard/mouse focus between the emulation occupying the SE/30's monitor and the host OS on the main screen.

If you were *really* clever, of course, you'd design the card so instead of putting the main CPU completely to sleep it would be able to make it act as a "slave" to commands from the USB bus target adapter, thus allowing you to leverage the in-ROM drivers for the floppy drive, etc; given how tricky the SWIM is to program it might be worthwhile.

Of course, this isn't going to happen, but it's an amusing thought.


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#8 2014-09-09 17:01:56

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,469

Re: SE/3000

LOL! We've actually been down this road before. wink

G3 -> PBX -> 68030 PDS = IIfxG3 . . .




In 2014, what's the really point of hacking anything from the 20th Century? neutral

.

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#9 2014-09-09 17:35:56

Eudimorphodon
Member
Registered: 2014-09-02
Posts: 525

Re: SE/3000

Mostly my point would be if you're going to go to such as extent to hack something you might as well make it as widely applicable (and replicable) as possible. Something that involved burning chips off increasingly rare machines' motherboards and shuffling them around to new custom circuit boards (and writing massive amounts of driver software) is pretty much going to have an audience of "one", the guy who does it to please himself.

In *theory* a new-build PDS card that turned an SE/30 into a magic desk companion that can actually be integrated with your modern workflow (IE, you could use the keyboard and mouse, and if you didn't want to run a Mac emulation all the time you could write some trivial software that would use the SE/30 screen to display widgets/clocks/whatever similar to what people do with those accessory USB displays) without doing irreversable damage to the SE/30 itself (or any other rare and hard-to-find antique) might be attractive to... at least a few people? I dunno. The fact that such a card would, even if you assume that all the engineering was "free", probably cost between $200 and $300 in parts alone is sort of a buzzkill. (Although given what the crazy SE/30 collectors pay for parts for those machines it just might possibly be sellable in "tens of units" quantities.)

Strictly speaking really what I'm envisioning here is similar in spirit to this "turn a Mac screen into a USB display" hack here:

http://spritesmods.com/?art=macsearm&page=5

Except instead of replacing the Mac's motherboard and limiting the functionality to just being a slow accessory framebuffer we end up with something that offers full access to everything originally connected to the SE/30. (Again, if you could make it capable of reading Mac floppy disks directly to a modern machine it could actually offer practical value to the right person and bridged access to SCSI disks might also be genuinely useful.) Heck, might as well go all the way and set up the device so it can bridge Appletalk packets across the SE/30's serial ports...

But, well, I suppose when you consider you could do most of the "data transfer"-related gimmies with a plain SE/30 equipped with an ethernet port and the right software it all loses the plot again. Never mind! wink

Last edited by Eudimorphodon (2014-09-09 17:36:25)


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#10 2014-09-09 21:31:10

techknight
Member
Registered: 2014-05-22
Posts: 453

Re: SE/3000

If it were me I would clone a beaglebone or raspberry pi onto a pds card with an fpga and the appropriate level shifting logic.

This would open up endless possibilities. Having a linux based coprocessor running in the mac could open up tons of features and expansions. Usb, Ethernet to name a couple.

Your mac application or extension/driver could look for the card then once found, push the appropriate linux code/app to the card and tell it to execute.

This code could be any coprocessing task. Mp3 capabity, flash rendering, html5 rendering, emulated apple/ne2000 Ethernet driver, usb mass storage. Etc...

Or with the appropriate fpga configuration,  push a 68k or even ppc runtime to the card and it becomes an accelerator.

Or put DDR3 on the card and program the fpga. Now it becomes a ram expansion

Last edited by techknight (2014-09-09 21:39:10)

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