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Power Mac 7220

I've recently dug back into Macromedia Director disassembling with a goal to help finish an engine that can run movies under ScummVM. I've always wanted to make Gadget run on random hardware... and for that matter, on newer versions of windows without issues. To get this done, I've had to create permuatations of Director movies to be able to decode the bytes. For example, text labels on Director stages/frames can have fonts, styles (bold, underline, etc..), font sizes, margins, borders, box shadows and text shadows. Each of these customisations react against the others and therefore all permutations need to be given to be able to render stages correctly. To do this, I've been using BasiliskII, but it tends to dislike loading Director after closing it.

So... that's the brief... what's the answer? Since I've gotten rid of my Quadra 950 and Power Mac 7200, I scoured eBay to find a replacement. Turns out that a Power Mac 7220 (aka 4400) (aka not-really-a-mac) was available; two units, two keyboards, two mice and a monitor, actually. I only wanted one unit, but got a good offer to take the whole lot.

Tear-down

All items were quite dirty and so a complete tear-down was required.

That's not sepia tone.. that's a solid layer of 'protective' dust. I usually use that excuse with my car, but not with computers. The entire system was caked, so it received a solid once-over.

Nothing better than finding spider eggs... bleach fixed that.

Apart from the external case screws, the rest of the machine came apart with brute force. It is said that this Macintosh is as close to PC as possible... so it's very PC-like regarding IDE devices and case screws.. but then the Apple comes through with a perfectly dismantle-able case.

The motherboard was slightly grotty! It all came up good after a wipe and vacuum.

Of note: No fan on the CPU? AT-style power connectors. IDE connectors, but it seems that they're the same channel when you follow the traces (i.e. a header for master and a header for slave.) Crystal sound chip? Does apple ever use this? Built in ATI Graphics. "Feature Option"? First RAM slot is for "Single Bank" whereas the second two are "Dual Bank"? (I've read that this means you can have a 32mb in the single and 64mb in the doubles.)

Power Supply Test

The power supply looked to be in good shape externally and I didn't feel like opening it. I decided to take the punt and switched the machine on.

It chimed! The hard disk then started booting... All was going well until I heard the disk park the heads. It's a really scary event for a hard disk as it only happens when the disk itself knows it's in trouble. This is an old Quantum 1.2g and so the fact that it parked meant its basic error checking kicked in. The booting stopped as the drive was beeping. Not an overly audible beep, but it seemed to be fighting requests from the machine to fetch any more data.

Subsequent boots failed to produce happy disk-reading noises... it was parked for good. I'll need a screen attached to be able to see what's going on... and I'll need a video cable for that.

VGA Cable

I used the forum post here as a reference to wire up a VGA cable. I used an old VGA cable that I had in my junk box and purchased a male DB-15 connector and ribbon cable from Jaycar. After stripping and tinning both sides, I mapped out the VGA cable. The Macintosh side was easy enough as the IDC cable was, from the red wire, 1, 9, 2, 10, 3, 11, etc...

Heatshrink came in very handy to keep everything isolated. Make sure you choose a size that is wide enough to slip over everything you want it to. ALSO make sure that you don't try to slip it over whilst the solder is still hot! ALSO make sure you remember to slip the heatshrink on before you solder the wires :)

I initially tested on an LCD, but the Apple Multiple Scan 15 Display M2978 also worked first time! But gets very blurry after 30 minutes of usage.

I shut the machine down and gave the HDD a little 'love tap'. Usually when the heads are parked (or stuck?), a tap can dislodge them. Of course, it could be that the magnet that locks the heads in place was just sticky... maybe the drive was wearing itself out trying to un-stick the heads. Either way... the small jolt did the job!

PRAM Battery

There's no chance the battery still worked. It's also quite difficult to find an off-the-shelf replacement.

I ended up at Jaycar and found a 3AAA battery holder. Using a bit of extension wire, I snipped the plug off the dead battery and wired it all together.

The cable was run under the CD-ROM chassis and placed right next to the HDD. Taped up tight also... any effort to prevent future leakage (and terminal shorting) is appreciated.

CD-ROM Drives

The IDE drive that comes with this machine did not like booting from CD. It might just be that my CDs were copies, or that the drive itself was faulty. I tried two other IDE drives, but had no luck trying to boot from them. I then tried a SCSI CD drive, but that wouldn't boot either. In fact, the SCSI drive needed the Sunrise CD driver to even recognise CDs. So, any IDE drive will work with the base drivers, but if you want to boot off a burnt CD then you will possibly need a real Apple SCSI drive.

Of course, I've learnt all the above before with my previous Quadra 950. It's amazing how quickly you forget these things. The Power Mac 7220 was also locking the IDE non-Apple drives and they were getting quite confused. If you soft reboot when the drive is locked then you can quickly have an unusable drive until you power down the entire machine.

Again, just stick to real Apple CD drives and real Apple CDs.

Actually, with further googling, it turns out that there might be ways to correctly burn and make bootable a CD image. Supposedly the System Folder needs to be 'blessed'. I would've expected this to be already the case in the bytes inside the ISO image, but supposedly not. I might try Toast on the Mac and burn a disk image and test from there. Here's a good guide.

Extra IDE Disks?

There's two IDC headers for IDE connections on the motherboard. Looking closely at the board, you can see parallel traces running between the headers, so it's pretty safe to assume that they're on the same bus. From this you can then assume that the CD-ROM header is hard-wired as slave with the HDD header as master. Disregarding this assumption, I tried to plug two HDDs on the HDD port.

I had an 80-pin IDE cable on hand, but it turns out these are 'keyed' with one blocked pin. This doesn't fit the header on the motherboard. Instead I found another IDE cable. The second drive is 200gb and was seemingly busted... clicking badly! I found another HDD, this time 500gb.

The Apple booted up both times in this configuration, but never saw the second drive.

SCSI Disks

I've always been interested to know how 50-pin cables convert to 'Printer port' DB-25 pin plugs at the other end... turns out that this motherboard has a SCSI controller and a 50-pin IDC header that has an adapter to an external DB-25 port!

Ok, so ... every second pin is skipped? Half-duplex over full? Totally interesting! Fortunately, I had a cable to convert it back to 50-pin and tested out my dual-drive external bay. All worked flawlessly, even though the second disk was incompatible... will need to install PC Exchange or something else... I don't even know what's on the drive!

RAM

The 200mhz version supports up to 160mb. So that's two 64mb DIMMs and one 32mb. The recommended spec is Unbuffered 60ns Non-ECC 3.3 volt DIMMs. Even though it is mentioned here, here and here that ECC RAM can be used in non-ECC motherboards, this does not hold true for older Power Macs. G5 and higher were able to support ECC.

Network Card

Both machines came with the same network card in them. It's a Communications Slot II profile card, with very little information on it. Most information on the 4400/7220 indicates that it either has a 'built-in' card or just comes with a standard 'Apple CS II Ethernet' card and the aptly named extension from the Mac OS CD will work.

After re-installing OS 8.6, I could see the driver in the extensions folder, but there was no network link light. The device showed up in System Profiler, but with very little information.

I then tried OS 9.1. It is the last out-of-the-box compatible version with my machine. During both installs, I couldn't boot from the CD, so I performed a clean install over the top of 8.6. Neither made the ethernet work.

The card has "BD-064 REV a." written on the top. "GSEP-M01" and "94V-0" on the back. Also "805-1614-A" on the face-plate. Googling for everything but the first item came up with zero results.

Finally, I found this post (6 months old!) from someone in the same predicament. The post author indicates that there's more information near the ethernet port. It sure as heck isn't on the board...

Oh what? It's on the face-place.. under the removable face-plate? Nice work. Actually, now that I think of it... the removable 'face plate' is only used for this type of PC-style case. In a usual Performa (or other Power PC), this piece of metal, which obscures the relevant information required, would not be obscuring the relevant information required!

The author of the post above reported the same model number, so I used the drivers he specified. I tried to use a floppy to copy over Sonic Systems EtherLAN 7.8 Drivers. This didn't work on either the first, second or third attempt. I kept getting serious disk errors on the Macintosh side, so I think the floppy drive is gone. I therefore resorted to wasting a CD-R and copied the driver, plus some other bits and pieces, over.

Installation was a breeze... the link light lit up right at the end of the boot process just before the desktop and then I tried Internet Explorer... poor machine ground to a halt! 48mb of RAM seems to be insufficient.

Macromedia Director

3 is throwing "An error of type 2 occurred". I haven't tried 4 yet. One step at a time!

Turns out that Mac OS 8 is the last version that Director 3 will happily run on. I've created a partition specifically for this version. Director will open on 8.1 and 8.5 (getting past that error above), but then crash when trying to load movies. Mac OS 8.0 is the safest version to use.

Mac OS 9.2.2?

Nope. The 'Tanzania' motherboard that this Macintosh is based on does NOT support anything higher than OS 9.1. OS9 Helper which I used on my previous 7200 does NOT support this model. Don't even try!

BeOS 4.5

Turns out this is one of the few Power Macs that can run BeOS! I also have the CDs. Will test this out in short order.

Linux?

Sure, why not. Instructions are all over the internet.

Overclocking

The motherboard hardly has a passive heatsink on the CPU, so it can't be getting too hot during runtime. This gives an option to consider overclocking it, as we can just put a fan onto it!

There's a few links here at apple fool indicating overclocking the PowerMac 4400/160 and the Tanzania Motherboard. The first article is a dead link but web.archive comes to our rescue here. The basic idea:

How to update you PowerMac 4400/160 to a 4400/200:
1. Locate the SMD-Resitors R1 and R9 on the Logicboard. There on the left side of the CPU.
2. Remove R1 and R9 carefully and solder a 10K resistor to R2 and 10K to R8.
3. Attach a Fan on the Heatsink of the CPU.
4. Yes, now it runs at 200 MHz.

Ok, but we have the 200mhz version. Thanks again to web archive, here's the link on the Tanzania Motherboard. The blue box, up in the top-left corner near the CPU is where our settings are (or the bottom-right area below on my photo.)

R8 and R9 are below the CPU OPTION pads with R21-24 above. The SMDs are tiny, so shifting them around will be a nightmare. By the table, we'd only need to shift R9 to R8 to get 220mhz and then, if that was stable, R21 to R22 for another 20mhz to 240mhz.

As that the components are already on the board, it can't be too hard to try... I also have a spare machine! Supposedly you can also change the base bus clock frequency from a 40mhz xtal to 50mhz and get a quick boost!

I'll tinker once I've got the machine stable.