128K/512K Supermac Enhance Upgrade Board

[Mac128]

Here's an auction for a Supermac expansion board for the 128K/512K Mac. It appears to have a connector which the seller describes as an expansion slot, however, it appears to be more of a SCSI hard drive connector. The copyright on the board is 1986 after the introduction of the Plus ROMs. Since the board appears to require a CPU socket to be attached to the motherboard, this upgrade likely required professional installation. However, did this upgrade board require the ROMs be upgraded too? Or did it use the original 64K ROMs (in which case the board implements its own SCSI compatible with the old ROMs)? Anybody know anything about these boards?

 

[JDW]

First of all, thank you Mac128 for continuing to spot these most interesting items on EBAY for us. I view EBAY daily for old Mac stuff, but I don't often see the goodies you dig up for us. Keep it coming!

I have a stack of old MacUser magazines at my parent's home in California that date back to 1986. If I had them here in Japan, I could quickly flip through them and find out more information. No doubt there was an article about it in MacUser and/or MacWorld, and possibly in an issue of Byte. Am I the lone soul on this site with old Mac magazines? Surely there must be someone else who has some and could take a peek for us.

 

[trag]

Am I the lone soul on this site with old Mac magazines? Surely there must be someone else who has some and could take a peek for us.

I threw most of mine out many years ago. Too much stuff. Of course, now I have a new pile of old stuff which is too much.

That looks like a fairly standard implementation for the day. Replacement 68000 running at the regular old 8 MHz, memory decoder logic, SIMM sockets for memory expansion, and a SCSI controller chip and SCSI connector. So you'd need the newer ROMs in order to get the benefit of the SCSI port.

That's actually quite similar to the NewBridge/NewLife upgrade for the same machine. The NewLife upgrade had eight SIMM sockets, IIRC and could use the on-board 512K of RAM ( couldn't use the 128K in a 128K machien) so one could install a pair of 1 MB SIMMs and six much more affordable 256KB SIMMs and have 4 MB of RAM.

There was a point where 1 MB SIMMs were over $100 each but 256KB SIMMs were about $5 or free depending on how hard you looked.

 

[JDW]

I've searched and search for information, but I'm not much farther along than when I started. I found one thread on the CCTALK Mailing List that talks about this exact card. See that post in this Google Search. But alas, Google has no cache of it and the CCTALK archives are offline!

So I set about to find old SuperMac Technology employees and write to them individually. I got two responses, one from Peter Glaskowsky and the other from Dr. Doug Gilbert. Dr. Gilbert was a design engineer at SuperMac from 1986. He told me the "that card doesn't look familiar to me at all." He then suggested I speak with David Silon via Linkedin, so I created a Linkedin account only to find that I have to upgrade to an outlandish fee-based system to simply email members! Mr. Glaskowsky worked at SuperMac in the early 1990's, so I was not surprised when he told me "I don;t know anything about that device." He then suggested I sign up for the CCTALK mailing list, which apparently he reads every day. I tried and failed to do that via the website, but Mr. Glaskowsky then wrote me back to say that I can subscribe via cctalk-request@classiccmp.org. Even so, I had to send a confirmation email instead of clicking on the link that came back in the response, as clicking on the link results in an error. But doing a manual confirm worked. However, the server then told me that a moderator has to approve me, and after 48 hours, this still has not happened. I wrote the moderator but he has not replied. I then told Peter Glaskowsky that Dr. Gilbert had mentioned David Silon, so he promised to forward my email query to Mr. Silon, but so far I've not heard anything from him.

All this work and still nothing!

It has been many years, but I still would have thought Dr. Gilbert would have known something in light of the fact this SuperMac board copyright is 1986 and he worked for SuperMac from that year. Perhaps SuperMac Technology OEM'd the board to another Mac upgrade supplier? But then, Dr. Gilbert should have known about that if such was true, I would think.

If only I was back in the US. Not only could I reference my MacWorld's at home, I could go to look them up at just about any library too. What conveniences you folks have there in North America!

For those of you reading this thread silently, who might think Mac128 and I are wasting our time on all this, you perhaps have not read old threads where we talk about 64k ROMs versus 128k ROMs. Most all cards that we have seen use the newer 128k ROMs in them. But the fact remains that some software is only compatible with the older 64k ROMs. Hence would be a truly "rare" and glorious find to discover an upgrade for the Mac 128k that retains use of the stock 64k ROMs. This has been the basis for all the work I've done thus far to discover more about this unusual SuperMac card.

 

[Charlieman]

I couldn't find any info in the handful of copies of US Macworld magazine that I own for 1986. SuperMac do mention their separate SCSI adapter for the 512K but not the Enhance. Below is what I found elsewhere, but I'd take the description with a pinch of salt

Australian Macworld magazine, April/May 1986 issue. Advert on back cover for SuperMac products by their local distributor Deermont Designs. The advert shows a photo of the back of a Mac 512K with a SCSI port emerging from the battery cage.

"ENHANCE

SuperMac Technologies now give you all the power of a MacPlus in your existing Mac. The Enhance board clips directly to your 68000 microprocessor, giving you two full megabytes of contiguous RAM. Because we use the same SIMM memory modules that are incorporated in the MacPlus, Enhance can be expanded to more than six megabytes of RAM!!

Compare this with only one meg of memory of the Mac, and we would be a winner, but that's not all... Because we use a twelve and a half megahertz chip to power our board it runs at an amazing twice the speed of the already speeded up MacPlus.

To all this we give you a completely Mac compatible SCSI port. Our unique cable assembly mounts the SCSI port connector to the rear of your Mac without modifying your existing cabinet."

 

[MacOSMonkey]

As JDW found out above so many years ago, neither Doug nor Pete could help re: the Enhance board. Doug worked on video products and Pete worked in the chip design/sustaining space (Synopsis).

The Enhance board was a great product for the 512Ke Mac with the exception that the Killy Clip that hooked to the 68000 had frequent failures. It was a very low insertion count clip and failed when it was over-flexed (or when someone sneezed), resulting in poor spring force contact with processor. It might still be findable on AliExpress - I would have to check the part number.

With Enhance, if you happened to get a working clip and did a proper install, great! You might never have a problem. However, the only reliable way to connect the clip to the 68K was to solder it to the pins (and that solution remains true today in a retro context). In the '80s and '90s, some people needed multiple replacement clips (which may have been because of over-flexing the clip on initial install -- hard to say). After SuperMac was acquired by Radius, if you called in with an Enhance clip problem, you just returned your old Machine/Enhance and they sent you a MacPlus for free! The users loved that solution (even though it was technically slower than an 512Ke wiith an Enhance board).


Anyway, as above, by default, Enhance added 1.5Mb of RAM (6 x 256K SIMMs) and a SCSI port to the Mac 512. It also has an on-board 68000 that let it run about 30% faster than a MacPlus. The reason for the speed-up was that the base 68K could manage the screen buffer while the Enhance 68K talked to RAM. So, a Mac512+Enhance had an advantage over a single processor MacPlus that had to alternately manage screen updates and other RAM accesses.

Upgrading the Enhance:
Enhance could also take 1MB SIMMs for a total of 4Mb on board. However, in order for this kind of config to work, the board had to be a Rev 3 board and needed a PAL upgrade. The PAL upgrade part number was E6000 (E4000 was installed with 1.5Mb on board). So, if you happen to find a Rev 3 Enhance board that has an E6000 PAL installed, that is a great find. It means that it can be upgraded to the max config. If it has an E4000 PAL, then it is stuck at the lower 1.5Mb RAM config. See the picture below.

Also, with a Rev 3, E6000 board, the 4 1Mb SIMMs had to be installed in sockets 1, 2, 4 and 5 (dark sockets below), skipping sockets 3 and 6.


When users wanted to upgrade beyond 1.5Mb and had an old rev board, SuperMac would exchange the board for Rev 3 with an E6000 PAL installed. Otherwise, if they had a Rev 3 board with an E4000 PAL, SuperMac would simply send out a replacement E6000 PAL.

The original SuperMac part number for Enhance was STD 4110.
The power consumption, including the motherboard was 6.25W.
SCSI Compatibility: should work fine with contemporary SCSI devices.

The Enhance board came with a flutter fan. Make sure you install Enhance with a fan. It may get warm/hot. There are many newer/better options today. You could also put one on the upper air vents of the Mac. There are many options.

Basic Troubleshooting:
1. If you see black bars, that is the sign of a classic clip failure -- not making good processor contact.
2. If you see a Happy Mac on a black screen, that is because you have the wrong RAM config for the installed PAL. Use E4000 for 1.5Mb on board and E6000 for 4Mb on board (slots 1,2,4,5).
3. If you have software compatibility issues with software that relies on the explicit CPU timing of the Mac 512Ke, there could be issues because of the fact that the Enhance board makes the Mac run faster than expected (by about 30%, as above).

I think I also have an old marketing flyer around somewhere, but it is probably available on the web.

I hope this info is helpful to someone...but here it is for posterity. You never know -- an Enhance board could fall out of outer space tomorrow and land on my head at terminal velocity, which, I suppose, would still be 30% faster than a Mac Plus...and then who would answer these questions 14 years later? Instead, you now know as much as a SuperMac dealer did in 1988...and maybe more!

ps. And if anyone wants to complain about 14-year-old necro, please send all complaints to /dev/null.