OS 7 boot CD for Mac Plus?

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OS 7 boot CD for Mac Plus?

Hello and greetings from Switzerland.

Before getting to topics let me introduce myself a bit. I'm a private collector of old NeXT, Atari and Apple hardware, living in Switzerland and as long as being no native speaker I hope You can understand my English...

I do have a problem that I can not solve and I'm looking for clues regarding my Macintosh Plus.

This nice littele machine ran Mac OS 7.5.5 off an old Rodime HD for nearly three years as a webserver using MacHTTP. Now this Rodime HD has gone to see its maker and I'm facing the fact, that old drives that can be used by the plus are harder to find than other hardware I already found.
Before I once installed a OS 7.5.5 off that harddisk onto a Iomega Zip and the Plus started off that one, too, but he does NOT start form a installed minimum os 7.5.5, which was placed onto a Zip by my PowerBook 145b. So I think any OS has to be installed off the Plus in order to run.

As it is getting harder to find 800k floppies, too, I thought about creating a bootable OS 7.5.5 CD for the Plus. I just tested this ability by placing an old PowerBook 1400c installation CD into the 600i CD ROM and the Plus started up to the point, where he stated that this CD can not be used by the Plus - the resources for the Plus were missing because this CD is solely for the PowerBook 1400c. I expected this but the Plus booted of that CD in the beginning so it seems to be a problem that can be solved.

As long as Apple's disk images of OS 7.5.3 and 7.5.5 only provide a installation but not a bootable system folder I began to wonder if it is possible to create a minimum bootable system CD for the Plus in order to install a 7.5.x off that CD onto a Zip connected to the Plus. I'm missing a "universal" OS 7.5.x installation CD, the only on I own is that PowerBook 1400c one.

So does any one have an idea or clue? I would like to rely on Zip cartridges as long as those are cheap and still available, old harddisks would be even better but in both cases I need a bootable system for the Plus NOT placed on a floppy - these can get broken easily and are harder to find day by day.

Thanks in advance!

J

P.S.: just in case someone is interested in and does not bother about the fact that my homepage is written in German solely You are welcome to have a look at http://www.blackmac.ch . There I'm introducing some of my old hardware and more is to come 😉

Macintosh Plus, Mac OS 8.6 or Earlier

Posted on Jun 18, 2007 11:26 PM

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Answer 1

Jan Hedlund

Level 7

23,881 points

Jun 19, 2007 5:57 AM in response to Shiner LE

J,

I'm missing a "universal" OS 7.5.x installation CD

If you choose Custom Install in the (downloadable, e.g. French, German and US) System 7.5.3 installer, you should find a universal system for all Macintosh computers as a system software subsection.

Alternatively, you could use the system folder of an appropriate bootable floppy (maybe the Network Access Disk 7.5 here or a Disk Tools disk; modified with additional extensions and control panels, as needed). An NAD 7.5 system folder, drag-copied to a hard disk, will (normally) boot any Mac computer introduced before November 1994.

Whenever a CD-ROM drive is involved, the system folder will have to contain a CD-ROM extension (such as Apple CD-ROM 5.4 here).

Creating a bootable CD is not uncomplicated. The result will depend upon the technique and burning software used. For anything but a basic system folder, please note that the operating system will have to have some place to save its preferences, so actually running the computer will most likely require a (hard) disk drive of some kind.

I noticed that you do not really want floppies; otherwise 800K System 7.0 disk images can be found at the Apple download site (for example, the British version; create bootable disks via the Make A Copy button of Disk Copy 4.2 on another Mac with a built-in floppy drive).

Jan

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Answer 2

Shiner LE Author

Level 1

0 points

Jun 19, 2007 11:11 PM in response to Jan Hedlund

Hello Jan and thank You for Your reply.

I've tried the following procedures:

1. installing a standard OS for all Macs onto Zip
2. installing a minimum OS for all Macs onto Zip

As long as I do not own a hard drive for the Plus this seemed to be the only way but none of them worked, maybe because of the fact that I started the installation off a PowerMac.
So I changed this procedures:

I used as many 800k floppies as I still own and DiskCopied all of the 7.5.3 images to them in order to boot the Plus and install 7.5.3 onto a Zip connected to the Plus. As I forgot to copy the Iomega extension to the first floppy the Iomega drive wasn't recognized (who wonders...) so I tried to copy that extension to the first floppy: not enough space!

This is why I need a startup CD...

J

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Answer 3

Jan Hedlund

Level 7

23,881 points

Jun 20, 2007 8:06 AM in response to Shiner LE

Hi J,

What happens if you use another Mac (your Power Mac?) to create a Network Access diskette (link in my previous post), then (still on that other Mac) drag-copy the System Folder of the (1.44 MB) Network Access floppy to an empty Zip disk, and finally add any necessary extension to the system folder (now on the Zip disk)? Are you absolutely sure which extension to use with a Macintosh Plus (I am by no means a specialist as far as Zip drives/disks are concerned)?

If you move the Zip to the Plus, does this arrangement boot the computer?

If yes, take the Zip drive back to the other Mac. Now, copy the System 7.5.3 files (in the case of the German version, totally 17) to the Zip disk. Make sure that you have decoded the MacBinary (.bin) first (using StuffIt Expander on a Mac). If everything is correct, you should have one .smi and sixteen .part (no .bin suffix) for the German version. Place these decoded files in a common folder on the Zip.

Move everything once more to the Plus. Start from the Zip (its temporary NAD 7.5 system folder). Try to mount the total System 7.5.3 disk image. The installer will be found in the mounted image.

BTW, I am not quite certain about what you mean by "I used as many 800k floppies as I still own and DiskCopied all of the 7.5.3 images to them". The downloadable 7.5.3 files together (once decoded) constitute one large disk image that can be mounted when one double-clicks on the first file. Each file is small enough to fit onto a 1.44 MB floppy disk (but not 800K). Did you somehow use the script-based segmenting option of Disk Copy 6.3.3, or another program, to distribute parts onto multiple smaller diskettes?

Jan

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Answer 4

Jan Hedlund

Level 7

23,881 points

Jun 20, 2007 8:43 AM in response to Jan Hedlund

Addendum

Is the Zip disk formatted in a way that the Plus can read?

If you wish to carry on with experiments involving a bootable 800K floppy instead, you should be able to modify e.g. the British System 7.0 Disk Tools (link above). You could begin by creating the floppy on another Mac (the Make A Copy button of Disk Copy 4.2). Then move everything not immediately necessary (such as Disk First Aid and Apple HD SC Setup) to the Trash (and empty the Trash from the Special menu). This should provide enough space for at least some smaller extensions.

However, please bear in mind that a minimum of System 7.0.1 is said to be needed to mount a self-mounting image (.smi). System 7.5 seems to be better, though. So, if you boot a computer with only System 7.0, and want to access the System 7.5.3 installer, another approach would be required. You may want to try to mount the System 7.5.3 total disk image already on the other Mac, and drag copy the entire mounted image (not the one plus sixteen files) to the Zip (or a hard disk). The difference is that the seventeen files take up approx. 20 MB, whereas a copy of the mounted image needs slightly less than 40 MB. If you are lucky, the installer will run under System 7.0 (I have not tested this).

Jan

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Answer 5

Jan Hedlund

Level 7

23,881 points

Jun 20, 2007 9:37 AM in response to Jan Hedlund

Addendum to the addendum

The aforementioned British 7.0 Disk Tools might not have been the best suggestion regarding modifications/additions. I just studied a floppy created from the downloaded file. The system file on this very disk in fact looks like System 6, and that is something different.

Jan

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Answer 6

Shiner LE Author

Level 1

0 points

Jun 21, 2007 11:44 PM in response to Jan Hedlund

Hello Jan!

Thank You very, very much for all the helpful hints and links! I think I will do it the conventional way: I just got myself an old Apple 40 MB hard disk and install a 7.5 onto it - DiskCopying the images shouldn't be the problem.
But I still would like to build a bootable CD for the Plus. Is it possible when using a working OS 7.5 on a hard disk? I think this will get pretty hard because the Plus only has 4 MB RAM.
Do You have any idea to this?

Thank Youonce again very very much!

J

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Answer 7

Jan Hedlund

Level 7

23,881 points

Jun 23, 2007 3:37 AM in response to Shiner LE

Hello J,

I just got myself an old Apple 40 MB hard disk

That is probably a very good idea. The earlier problems with booting could have been related to the Zip (either a driver incompatible with the Macintosh Plus, or a compatible driver that had been corrupted or exchanged when used on a more modern Mac; or possibly the formatting). Remember that an old hard drive used with a Plus may have to be formatted in a special way, with an interleave factor 3:1. This is usually automatically accomplished by formatting the drive when connected to the Plus. One can also, in some cases (a hidden feature in Apple HD SC Setup) set the interleave factor manually, which allows formatting at another Macintosh computer.

and install a 7.5 onto it

The earlier booting issue may also have been linked to a system folder that was not properly active. One can "bless" the system folder by double-clicking on the System file; or by moving the System file and possibly the Finder out of the System Folder, closing the windows, then move the file(s) back in. I guess that you with the new hard drive will be able to install a working operating system, even when creating a system folder from one of the universal options ("for all Macs") on another Mac.

But I still would like to build a bootable CD for the Plus.

Sorry, I am not an expert in this field. There are two web pages ( here and here) at the Low End Mac site dealing with similar subjects. Could details there be of interest to you? And, as always, read the software licence agreement(s) carefully in order to stay legal.

Alternatively, you could decide not to make the CD bootable. With a bootable disk (a floppy or the hard disk) containing the appropriate CD-ROM extension(s), the CD and its contents (no need for a system folder there then) would still be visible.

Disk Copy 6.3.3 is available for download from Apple ( German version, US version).

Jan

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Answer 8

Jul 15, 2007 1:01 PM in response to Shiner LE

You can use modern (1.44MB) floppies in the 800K drives, so long as you do not mind not being able to utilize the leftover 644KB. Just format them on the Mac Plus itself and they will work ok. I know this works because I had to do this when I wanted more disks for my own Mac Plus.

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Answer 9

Jul 15, 2007 1:18 PM in response to Shiner LE

The Mac Plus does not have a built-in driver for Zip or for CD. These boot devices came long after the Mac Plus was released.

To boot from Zip or CD, you will need a way to get the Zip or CD driver into memory at the beginning of the boot process. When the very first Hard Drives were added to Mac 128Ks, the Hard Disk driver was not in the Mac ROM. You had to boot from a special floppy, which loaded a driver that allowed you to boot from the Hard Drive.

Any 50-pin SCSI Hard Drive under about 2 GB should work on the Mac Plus. For performance reasons, you will want to format it for use on the Mac Plus using HD SC Setup, using a Disk Tools floppy. Otherwise it will seem very slow. I do not recall whether HD SC Setup can partition a larger drive into an under 2 GB Volume. A 40 MB drive when the Mac Plus was new sold for over US$1000.

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OS 7 boot CD for Mac Plus?