68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
68030 accelerator for the Macintosh Portable, redux.
Posted by: Bolle on 2026-07-15 05:33:31
if we leave out the VGA video interface. @Bolle already published the JEDEC files for the Vandal Extreme, which seems to be a clone of the Gemini Ultra/Integra.

From here, the main hurdles are reverse-engineering the schematics from the PCB and dumping the configuration PROM to figure out exactly how the Xilinx XC2018 handles host bus management. @Phiply mentioned that dumping that PROM should be possible.
Oh, I built a proof of concept kind of clone thing a long time ago already but haven't pursued it any further because availability of those Xilinx chips and the clock generator IC they used for the pixel clock is meh...
Vandal.jpg

it is highly likely that the Xilinx XC2018 simply replaced the 74646 transceivers and their control logic
Indeed, that's what it does. Not sure why they choose to do that instead of properly driving the bus with actual bus drivers.
Posted by: Builder68 on 2026-07-15 05:44:48
Oh, I built a proof of concept kind of clone thing a long time ago already but haven't pursued it any further because availability of those Xilinx chips and the clock generator IC they used for the pixel clock is meh...
View attachment 101352


Indeed, that's what it does. Not sure why they choose to do that instead of properly driving the bus with actual bus drivers.
Oh!, I also suspect you already did it 😉. Of course you had a working prototype tucked away in a drawer somewhere!
Posted by: Froggy814 on 2026-07-15 07:42:23
Hmm, this seems like there are a lot of variables... Unfortunate nobody ever made one.

So I see the main problem is the clock timing. Then the other problem is making it compatible with the Power Manager. Is that really the big issues? Or is there more I am not seeing?
Posted by: Builder68 on 2026-07-15 08:39:40
Hmm, this seems like there are a lot of variables... Unfortunate nobody ever made one.

So I see the main problem is the clock timing. Then the other problem is making it compatible with the Power Manager. Is that really the big issues? Or is there more I am not seeing?
The video buffer?

On the Portable, it's actually a fully asynchronous, on-demand handshake. The system completely decouples the CPU from the display refresh logic.

On early Macs, though, it’s a pretty synchronous operation. Because of that, there's really no easy way to make an existing 68030 accelerator compatible with the Portable.
Posted by: Froggy814 on 2026-07-15 09:04:18
Well, I guess it would be a good idea to make a list...
Posted by: Builder68 on 2026-07-15 09:12:09
Well, I guess it would be a good idea to make a list...
Or even better, take the challenge like a new hardware design from the scratch.

If someone wants to take on this challenge, they'd really need a deep, inside-out understanding of the Portable’s hardware. And honestly, just getting to that point is a huge challenge in itself
Posted by: Froggy814 on 2026-07-15 09:14:29
That would be really hard! And it would still require a list! At least of what you need to add to the card... 🙂
Posted by: Trash80toHP_Mini on 2026-07-15 09:34:29
Regarding the Micromac Performer, I think there might be a good chance of making its handshaking with the host fully asynchronous, which could let us push the clock speed up to 33 MHz.
That'd all but make it a Performer Plus I think? I'm wondering if the asynchronous handshaking section of that upgrade could be reversed? Grafting that section into the low end Performer would cure what ails it? That's not a full card clone, but a hybrid might do?

Can't find the Performer family link, but main page is here. https://www.micromac.com/


Performer Plus is missing, but may only be for the Macintosh Plus according to a downloads page? That or the software/driver download is only for the Performer Plus? IIRC it sat between Performer and the Performer Pro on the comparison chart and had a higher clock than Performer and cache? At any rate, being for the Plus it may be early enough to crib the timing mechanism? Hopefully the Pro's handshaking mechanism can be reversed. Everything from there on is likely a no-go?
Posted by: Froggy814 on 2026-07-15 09:47:28
That's no a full card clone , but a hybrid might do?
Possible... There are a lot of variables that are hidden until they become apparent though...

A runt of accelerator cards! I like it!
Posted by: Builder68 on 2026-07-15 10:34:21
That'd all but make it all but a Performer Plus I think? I'm wondering if the asynchronous handshaking section of that upgrade could be reversed? Grafting that section into the low end Performer would cure what ails it? That's no a full card clone , but a hybrid might do?
More like a Performer Pro, actually!

I'm guessing you hit "Reply" just a few scrolls before reaching the next thread where @Bolle ended up spoiling the ending to this exact mystery. 😉
Posted by: Froggy814 on 2026-07-15 12:22:38
So I did a heinous thing... I asked AI what the steps for power up would look like...


does this look like what would have to be added for the MicroMac Accelerator? Then the opposite for turn off?

Power button pressed
|
v
Macintosh Power Manager turns on power rails
|
v
+5 V becomes stable
|
v
Power Manager asserts system RESET
|
v
FPGA/CPLD powers up and configures
|
v
FPGA holds 68030 in RESET
|
v
FPGA disables / isolates original 68000 bus
|
v
Macintosh RESET released
|
v
FPGA waits a short delay
|
v
FPGA enables 68030 bus control
|
v
FPGA releases 68030 RESET
|
v
68030 reads reset vectors from Macintosh ROM
|
v
Macintosh boots normally
Posted by: Trash80toHP_Mini on 2026-07-15 15:47:05
More like a Performer Pro, actually!
Nope, Pro had the full-on Gemini deal with 33MHz/Cache/Local Memory run on its local bus via Compact Virtual.
More like the Plus. IIRC Performer Plus was clocked at 25MHz and had Cache on board, but no provision for local bus VM memory/SIMMs.

That puts it at about the same development time frame as the Radius 25 Accelerator. Anyone got a pic of that one?

Anybody got a pic of the Performer Plus? Didn't MicroMac acquire the OEM for Gemini badged hardware?

I'm guessing you hit "Reply" just a few scrolls before reaching the next thread where @Bolle ended up spoiling the ending to this exact mystery. 😉
Saw it, didn't think the Vandal setup was necessarily pertinent to Performer hacking?
Posted by: Froggy814 on 2026-07-15 16:57:28
Anyone have this? It might be helpful if we could see the hardware. Do you know where we could fin more photos?

Hardware & Accessories - MacintoshPortable.info

macintoshportable.info macintoshportable.info

Second Wave ExpanSE Home BaSE​
Posted by: Froggy814 on 2026-07-15 18:25:46
What would happen if all you did was plug the 68030 into the same pins as the 68000 processor?
Posted by: Trash80toHP_Mini on 2026-07-15 19:59:40
Pin shortage and magic smoke emissions.
Posted by: Froggy814 on 2026-07-15 20:19:35
Pin shortage and magic smoke emissions.
Little kid footage: OOOOHHHHH, Can we do it again?

Thanks for the confirmation @Trash80toHP_Mini.
Posted by: Trash80toHP_Mini on 2026-07-15 20:20:21
Anyone have this? It might be helpful if we could see the hardware. Do you know where we could fin more photos?

Hardware & Accessories - MacintoshPortable.info

macintoshportable.info macintoshportable.info

Second Wave ExpanSE Home BaSE​

That one never got much coverage in the day. I wonder how Second Wave managed to address two SE Cards? Then again they were Masters of Black Macintosh Magic, capable of transmuting a single NuBus Slot into three or six!

The Second Wave ExpanSE SE/30 version is a Blue-Eyed Ginger Unicorn, seen once on eBay, but never touched. Auction pics are floating somewhere around these parts.

Expanse setup for the Portable is a friggin' ALBINO UNICORN! Its close relative may have once been spotted in a Squatty Potty commercial, but the Portable version has never been seen available for sale anywhere at any time to my knowledge.

Tangent alert! - Interesting DuckDuckGo/AI tidbit:

The “Second Wave ExpanSE NuBus adapter” is the key detail: a NuBus adapter for the SE/30 has to speak the SE/30’s memory/bus timing correctly (and physically fit), and many adapters designed for other models won’t. In practice, the compatibility problem is usually the NuBus controller (“NuChip”) generation and which bus-cycle type it expects—the SE/30 uses a different CPU/bus/memory-controller behavior than the machines those NuBus adapters were originally built for. 68kmla.org

What this means for your “Second Wave ExpanSE … for SE/30” question:

  • If the adapter was specifically made for the SE/30 (correct NuBus controller + firmware/signaling + correct PDS mechanical interface), it should work as a normal “get a NuBus slot” solution.
  • If it’s an adapter intended for an IIsi/IIcx-era NuBus environment (or otherwise not explicitly documented for SE/30), it’s at risk of failing to bus-master or reliably operate due to the NuBus controller / bus-cycle mismatch discussed above. 68kmla.org
  • Also, the SE/30 doesn’t natively have NuBus—so you’re always depending on a compatible PDS-based (or otherwise adapted) solution.
If you paste (or photograph) the exact model/part number printed on the adapter (and any “NuChip” markings you can see), I can tell you whether it matches the SE/30-compatible style or whether it’s likely to be one of the “won’t talk correctly” variants.

Interesting, more and more searches are being traced to some lunatics posts hereabouts?🤣
Posted by: Trash80toHP_Mini on 2026-07-15 20:37:27
Little kid footage: OOOOHHHHH, Can we do it again?

Thanks for the confirmation @Trash80toHP_Mini.
De nada, compadre!😆
Posted by: SuperSVGA on 2026-07-15 22:46:13
Anyone have this? It might be helpful if we could see the hardware. Do you know where we could fin more photos?

Hardware & Accessories - MacintoshPortable.info

macintoshportable.info macintoshportable.info

Second Wave ExpanSE Home BaSE​

I imagine most of the docking bases were forgotten or recycled unfortunately, since they look pretty worthless on their own. I've only found the PDS card, cable, and potentially the software.

I wonder how Second Wave managed to address two SE Cards?
It likely just remapped them to different addresses. Though it didn't seem to me that it had any DMA capability so I don't think accelerators would have worked in it.
On the SE version, you actually got four slots.
Posted by: Joopmac on 2026-07-16 01:53:54
Going to the store, getting some popcorn to enjoy during this thread
< 3 >