Mac SE/30 RAM Slots

My Mac SE/30 Part IV: Upgrade Plans

In Part III of this series I took out (and cleaned) the motherboard and disk drives of my Macintosh SE/30. At that point, I was stuck waiting for the upgrades I’d ordered to arrive. But what upgrades exactly?

As I’ve mentioned before, the SE/30 is one of, if not the, most popular model of compact mac ever made. That’s largely due to its speed and expandability – the SE/30 is essentially a powerful Macintosh IIx crammed into the smaller Macintosh SE case. Both the SE/30 and the IIx use the Motorola 68030 processor running at 16MHz with a 68882 FPU coprocessor.

However, despite the many hardware similarities, the SE/30 has one decided limitation: its ROM is “32-bit dirty”, while the ROM of the IIx is “32-bit clean”. What does that mean? Well, the ROM in a classic mac is essentially a bit of permanent software on a (ROM) chip that’s responsible for booting the machine and interfacing between the system and with the hardware.

I won’t get into the history, but having a “32-bit dirty” ROM means the system is limited to a maximum 8MB of RAM. So the SE/30 can only use 8MB of RAM, while the identically powered IIx can use up to 128MB. This doesn’t matter much if you’re running System 6 (which itself is “32-bit dirty” and can only use 8MB of RAM), but if you’re running System 7, it’s an annoying limitation.

But there’s good news! As it turns out, while the software in the SE/30’s ROM can not be updated, the chip itself is actually on a small removable SIMM board. Same with the IIx. So it didn’t take long for enterprising mac enthusiasts to trying putting IIx ROM boards into their SE/30s, and voila, it actually works! With the swapped ROM the SE/30 can see up to 128 MB of RAM. From what I understand, it was a very popular upgrade, and a big part of why the SE/30 became so popular.

My SE/30’s RAM

With that, let’s return to me and my SE/30. While I want the machine to look cosmetically as original as possible, I do want to upgrade the internals a bit, especially the RAM.

As I mentioned in the last post, my SE/30 has the max factory configuration: 4MB spread across four 1MB RAM sticks. I also mentioned that the original seller claimed that the other four RAM slots weren’t functional. Right off the bat, it seems that I’m already at the limit for this particular machine.

Now, if I could get my hands on a IIx ROM board, I could swap out my four 1MB sticks for four 16MB sticks, bumping the RAM to 64MB. Not the absolute max of 128MB, but still a very worthy upgrade.

However, if it’s hard and expensive to track down vintage macs in good shape, it’s even harder and more expensive to find upgrade parts, especially for popular upgrades and especially for parts taken from other vintage macs. But there’s more good news – we don’t actually have to track down an original IIx ROM board.

Modern ROM Replacements

Enter modern enterprising mac enthusiasts, who have created new replacement ROM boards. There are two options in the market today: the GGLABS MACSIMM and the BMOW Mac ROM-inator II. Both are relatively cheap ROM boards that can be installed in SE/30s, as well as other compatible models. Furthermore, both provide useful “customization” options for how the ROM works.

One useful thing they do is path the ROM to disable the memory test at boot. While the 68030 processor is a beast for its time, running a full memory test on 16, let alone 64 or 128 MB of RAM at boot can take up to a full minute. (For reference, when rebooting my SE/30, as-is with System 6, the machine is back to the desktop almost before the startup chime finishes.)

Another patch adds HD20 support, which is a useful (but older) protocol for hard drives that connect via the external floppy port. While I don’t plan on getting or using an HD20 hard drive, it’s useful to have because my Floppy Emu can emulate such an HD20 hard drive, giving me an easy way to transfer large files to and from the machine via SD card.

Now, it’s here that the two products take different philosophical approaches. The base MACSIMM model stops with just the two patches – no memory test plus HD20 support. There’s also a “deluxe” model which adds a built-in, bootable “recovery” disk, so even if you have no other disks installed, or none of them are booting properly, you can still boot into a working system to troubleshoot your machine.

The Mac ROM-inator II on the other hand, comes in only one model, which includes the recovery disk functionality, but also a lot of other customizations as well. The startup chime, a classic hallmark of vintage macs, has been replaced with their own custom tune. The “Happy Mac” startup icon is replaced with a custom “Pirate Mac”, and the startup menu displays some info like the amount of RAM installed, how to boot the recovery disk, etc. Price-wise, it’s also cheaper than both models of the MACSIMM.

My SE/30’s ROM

I want to upgrade my SE/30’s RAM to at least 64MB and I want the HD20 support. With the Floppy Emu and the SCSI2SD, I don’t think I really need the recovery disk. Also, in keeping with my desire for the machine to look and feel original, I was actually turned off by all of the Mac ROM-inator II’s customizations.

In the end, despite having to pay a higher price, I went with the MACSIMM. It helped a little that the Mac ROM-inator II was out of stock at the time. Also, when I contacted GGLABS to confirm that the MACSIMM did not include similar “stylistic” customizations, he explained that he too preferred the basic setup, though he’d happily reflash his board with whatever alternate ROM image I gave him.

So I ordered the basic MACSIMM module and started looking for more RAM. Thankfully, unlike with the protracted ordeal I had finding RAM for the Power Mac 8600/200, I found a seller with 16MB sticks of compatible RAM quite quickly, and at a price within my remaining budget. Still, I limited myself to only ordering four sticks – I reasoned that without any guarantees that all eight slots worked, I didn’t want to waste any money up front. Plus, other than it being really cool, I still wasn’t even sure I’d find a way to use 64MB at once, let alone 128MB.

Alright, now that the plan’s in place, stay tuned for Part V, where I start actually upgrading my machine.

/jon

Want to read from the beginning? Start at Part I.

Power Mac visiting The Old Net via IE 3.0.1

Adventures in Macintosh restoration Part VI: Booting up and jacking in

In Part V, I was able to boot my Power Macintosh 8600/200 from a burned system CD. Now it’s time to get a system installed.

Hard drive options

At this point, I can boot the Mac OS 8.1 system CD, but I don’t have a hard drive to install it to. The first, most obvious answer, is to just get an old hard drive and install it.

However hard drives, especially mechanical ones, can have a rather short lifetime compared to other computer components. So while getting an “era-appropriate” hard drive is possible, it would be a gamble. Not to mention this computer originally shipped with a whopping 2GB drive – old hard drives come in sizes so small you can’t buy anything with that little storage any more.

So why can’t I just buy a new hard drive and install it? One word: SCSI.

SCSI is a old set of standards (cables, protocols, etc) for connecting computers to drives, and isn’t really used anymore for modern computers. Broadly speaking, vintage macs used SCSI and vintage PCs used IDE. These days there aren’t any new SCSI hard drives. It’s part of the reason I was so happy the CD-ROM worked – tracking down a replacement SCSI CD-ROM could have gotten pricey.

What does this mean for me? I already have an alternative, something I had bought in anticipation of this problem.

Hello SCSI2SD

The SCSI2SD is a device which simulates one or more SCSI drives using an SD card. Like the Floppy Emu, it was designed for people trying to keep older hardware up and running.

It’s not as easy to use as the Floppy Emu – that device is pretty plug and play – you copy your floppy disk images onto the SD card and use its built-in screen and controls to select which disk to load at runtime.

The SCSI2SD has a steeper learning curve and requires a little more setup. It connects to your PC via USB and comes with a configuration utility which you use to define the devices, or disks, that the SCSI2SD should report to the computer.

However, instead of having disk image files, the SCSI2SD requires you to map these drives directly to sectors on the SD card. So if you ever pop the SD card into your PC, it’ll tell you the disk is unformatted and ask you to format it. It also means you can’t easily add and remove files.

Basically, once you’ve configured it to your liking, it’s a great drop-in replacement for a missing hard drive, and you can backup your data by making a disk image of the entire SD card. Adding or extracting individual files is possible but requires a lot more work and tools.

Out of the box the SCSI2SD is configured for a single 2GB drive, a safe size for SCSI machines. And since my goal at this point is just to get a system, any system, up and running, I just kept the defaults for now.

Installing Mac OS 8.1

Time to install Mac OS 8.1. I plugged in the SCSI2SD and booted the system CD. Then I opened the “Drive Setup” utility to format the new hard drive.

Not supported. 😦

See, on top of using a connection that no one uses anymore, Apple also put in measures to make sure that you only install “Apple-approved” components. In this case, the utility for formatting hard drives has a fixed whitelist of specific brands, models, and versions of hard drives that it can format. So it doesn’t like my fancy new 2GB drive.

There’s a couple ways around this. One is to find a patched version of the program, where enterprising hackers removed the whitelist. I could put that into a floppy image and use the Floppy Emu to load it. Another option is to use a third-party drive utility, again by putting it into a floppy image.

The easiest way however, is to simply lie to the program. 🙂

Despite being a bit complicated to use, the SCSI2SD config does let you configure practically everything SCSI-related, including the vendor and product information reported by each drive. So I just looked up which drives were supported back then, and configured my drive accordingly:

Once I had that set, Drive Setup worked just fine and I was able to initialize my new hard drive. All that was left was to run the Mac OS 8.1 installer, where I gladly accepted the defaults along the way.

First boot and Y2K20

When it rebooted, my first vintage mac in twenty years was finally up and running. It wasn’t the final setup I envisioned for this machine – having multiple versions of the OS on different (virtual) drives, ready to support whatever older mac I want to restore, but it worked. Moreover, so far all of the original hardware seemed to be in working shape. I could read CDs and read and write floppies. If I really needed to, I could even do the tedious work of injecting files into the SD card.

Back in Part III, I mentioned that the first thing when opening the machine up was to replace the PRAM battery. The PRAM battery is responsible for maintaining the clock and some settings, so the first thing I did when the machine booted was to set the clock. Now we run into a funny bit of history – the Y2K bug, or specifically, how it didn’t affect macs. Long story short, many vintage computers saved memory by only saving the last two digits when keeping track of the current year. Their clocks were essentially restricted to dates between 1900 and 1999.

Macs didn’t suffer from Y2K – from the beginning their clocks took dates from 1941 to 2040. But just because the hardware supports 2020, doesn’t mean they didn’t take shortcuts in the software – the control panel for setting the date still takes only two digits, and interprets them as being between 1920 and 2020. So macs have the Y2K20 bug. If you set your clock in 2019, it would have rolled over fine to 2020 and beyond. But there’s no way to manually change the date to 2020 to later.

Thankfully, enterprising hackers come to the rescue once again, with a set of patches for the control panel to let you set the correct date. So after installing that and another reboot, I was able to properly set the clock on this machine, and get on to the very first thing I really wanted to test on an up and running system – networking.

Connecting to the tubes

Even the earliest macs had built-in support for networking, but, as with SCSI, they used protocols and cables that aren’t in use anymore. Thankfully this isn’t one of the earliest machines, and as I mentioned back in Part II, this machine has built-in 10Base-T Ethernet, with the still-standard RJ45 Ethernet jack. It’s literally the slowest possible connection that can still connect directly to a modern Ethernet network without any adapters.

I’d also just spent the weekend running Ethernet cable to my office, for “work” purposes. 🙂

So I grabbed a spare Ethernet cable and plugged the old mac into my switch. A couple clicks through the Mac OS internet settings to enable TCP/IP, and quick double-click on Internet Explorer 3.0.1, and we’re off to the races:

Well, races is a stretch, but success! It’s literally 100x slower than my network can handle, but that’s still 40x faster than an old dial-up modem. A lot of sites won’t work on such an old browser, but I didn’t hook this up to browse the web. Network access means much easier file sharing with my modern computers. Still, I took it for a spin on theoldnet.com, and even filed a bug when the website for the product I work on didn’t load properly.

Well, that’s a lot of progress for one post. Stay tuned for Part VII!

/jon

Want to read from the beginning? Start at Part I.

Power Mac 8600 First Boot (About This Computer)

Adventures in Macintosh restoration Part III: The Power Mac lives!

In Part II, I described my first purchase: a Power Macintosh 8600/200 in pretty good shape. But I left the most important question unanswered – does it work?

Replacing the PRAM battery

First step was to replace the PRAM battery – the little cell that keeps the clock in-time when the system is unplugged, and maintains a small list of basic settings like the screen resolution, which drive to boot, etc.

You’ll notice in the previous post’s photos that I’d already removed the original battery – in fact it was the very first thing I did when I opened the machine up.

December 1996. Seeing as this model was on the market in 1997, that’s probably the battery’s manufacture date, making it almost 24 years old!

I tested it with a multi-meter and it registered zero volts, confirming it was dead, well past its expected life of ~10 years. Thankfully, and most importantly, it failed gracefully – no leaks and no explosion. It’s a real risk too.

Thankfully, replacing the battery was smooth and simple.

Connecting a modern display

After replacing the battery, the next step was to get the machine set up and connected to a monitor. The only loose monitor I had available was a cheap LCD I’d bought a few years ago.

While many vintage macs could output VGA-compatible signals, Apple had their own unique video connectors. I had to pick up a cheap configurable VGA monitor adapter (FYI, the correct setting was 2, 3, 6, 7).

With that connected, it was time to start up the machine!

First proof of life

The machine started up with a satisfying startup sound:

It lives! The blinking “missing disk” icon is the exact behavior one expects without a boot disk present. Which means, the next step is to prepare a boot disk.

Breaking out the Floppy Emu

Without an already set-up hard drive, the two standard options I have for this machine are a boot floppy or a boot CD-ROM. I’d ordered the original system install CD, but it hasn’t arrived yet. (Side note, I’m behind in blogging all of this, but I ordered the CD August 17th, it wasn’t even shipped until September 4th, and it still hasn’t arrived as of this post).

Could I have burned a CD? It turns out yes, but I didn’t know that, or whether the CD-ROM drive even worked.

Could I use a floppy? Not right away – I do have blank floppy disks, but as far as I knew, no way to make a mac floppy on my PC, even if I had a floppy drive (which I didn’t). And again, no guarantee that the floppy drive in the mac works either.

So, time to bust out my first “modern” toy in this adventure: a Floppy Emu. I mentioned back in Part I that there are modern devices that emulate the older drive hardware and use SD cards, and the Floppy Emu is just that. It’s a little device that plugs into the internal floppy cable (or external floppy drive port) of these vintage machines, and lets you read from (and write to) floppy drive images on the SD card.

I put several boot floppy images onto an SD card, disconnected the real floppy drive, ran its cable out the front of the machine, and connected the Floppy Emu.

It took a few tries with different images (some threw up errors saying they wouldn’t work on this particular machine) but eventually the Mac OS 8 Disk Tools 8.1 PPC worked. Success!

Booting from floppy was slow, and this particular floppy image is really just to help you set up / troubleshoot your hard drives, but I was finally able to prove the machine wasn’t a lost cause.

About this computer

When getting a vintage mac up and running, it seems it’s tradition to take a photo of this screen, showing off how much RAM you have and that you’ve gotten this far. I myself was pleasantly surprised – I had counted the four RAM DIMMs and after a little research had concluded that they were 16MB each, for a total of 64MB RAM. Not amazing by today’s standards, but twice the standard 32MB this machine came with.

Turns out one of sticks was actually 32MB, so 80MB for me! Considering the price and availability of RAM for this machine (we’ll get into that in a later post) every little bit helps.

I think that’s enough for this time, stay tuned for Part IV!

/jon

Want to read from the beginning? Start at Part I.