Mac128
Well-known member
I thought this deserving of its own separate post as the previous deals mainly with the flashing LED on the A9M0106 Apple 3.5" Drive.
A little history, Larry Pina mentions in his book "Macintosh Repair & Upgrade Secrets" on page 192 that a 128K with an 800K internal drive works just fine, giving you 800K of MFS storage. However, as I've criticized Pina before, he briefly mentions something ground breaking in passing, but gives few details, leaving the reader to infer that there's little else to it. Indeed, I stumbled on the solution accidentally and just assumed everything was working like Pina indicated. Then when I tried to repeat my success, suddenly the thing didn't work. This then is the result of backtracking through my original efforts and what I know know to be true.
ONE WORD OF CAUTION before you proceed. This is not yet etched in stone. The following procedures worked on my equipment and due to some fluke of hardware, may not be repeatable on other equipment. No one should assume this is a universal solution until it has been confirmed by others on this list.
First something I know to be true of both the Macintosh 128K and 512K. As Pina indicates, both of these Macs will boot from an internal 800K drive as long as it is Apple part number 661-0345 (Sony p/n MFD-51W-03), no other earlier drive mechanism will work (though possibly some later models). These drives will also read and write 800K MFS only disks. The Apple 3.5" Drive (Apple p/n A9M0106) which contains the afore mentioned drive mechanism, will also boot, read and write 800K MFS. However, the original Apple 800K External Drive (Apple p/n M0131) will not work without the HD20 INIT and then only to read and write pre-formatted 800K MFS disks as well as HFS) and you cannot boot from this drive with 64K ROMs.
Now for the rub. What Pina does not go into, is how exactly you get 800K MFS disks from which to read/write and boot on a 128K. And perhaps there's a good reason for that. Using System .97/Finder 1.0, S2.0/F4.1, S4.1/F5.5, I was unable to get a 128K or 512K to initialize/format an 800K MFS disk in either the internal or external drive. As JDW pointed out earlier, using the HD20 on the 512K only results in formatting an HFS 800K disk, which is unreadable without the HD20 INIT. So I settled for formatting a 400K MFS Single Sided disk both with the HD20 INIT and in a 400K external drive. Unfortunately, though readable in the 800K drives, any attempts to erase them as 800K MFS resulted in failures or system crashes without the HD20 INIT. The same thing happened with HFS formatted 800K disks (I did not try 400K HFS). So how do you do it?
One method that has been posted around the net, though does not specifically say so, requires a Mac Plus or 128K ROMS. Basically you boot up with a stock System 2.0/Finder 4.1 or earlier (the last MFS only System & Finder and pre-HFS aware), the MacPlus does not care about the HD20 INIT or need any other modifications to the basic system. For my purposes I used exclusively a MODIFIED (see below) 2.0/4.1 and everything that follows is based on that unless stated otherwise. Boot up with this system on a Mac Plus or 512Ke, possibly even a 128Ke (128K ROMs in a 128K Mac – not tested) and insert a blank 800K disk. If it is unformatted the Mac will ask you if you want to initialize and about :30 later, you'll have an 800K MFS disk. Even if the disk is formatted, Erase will accomplish the same thing. The resulting disk will work just fine in a stock 128K and 512K using one of the appropriate 800K drives.
Now you're asking the same question I was: so what good does that do me if I have 64K ROMs? Since you have to have 128K ROMs or the HD20 INIT to format in an 800K drive and the HD20 INIT will only let you format HFS, you're stuck right? WRONG. You're going to love the solution. The HD20 INIT was released with System 2.1/Finder 5.0 (the FIRST HFS aware System & Finder as far as I know) along with the HD20 Hard Drive. The Mac Plus with 800K drives quickly followed with 3.0/5.1 and that quickly followed by a succession of updates resulting in what is the widely accepted stable system 3.2/5.3 which Pina and others reference for use with the HD20 & 800K drives. The reason the MODIFIED (see below) 2.0/4.1 trick works on the Plus & 512Ke is that the System & Finder don't know about HFS, so I suspect the ROM translates the 800K driver info for it and then the Finder acknowledges 800K capacity, but it still only understands MFS. Once the disk is formatted with the disk capacity information, the Finder no longer needs the ROM to translate and any Finder will happily see the disk as 800K MFS. Now what?
Now, put a copy of the HD20 INIT on System 2.0/4.1 (and possibly earlier) MODIFIED with the S3.2/F5.3 Printer Installer (v1.1) AT ImageWriter (v2.3) ONLY (see below). Yup! When the system boots instead of "Hard Disk 20 Startup", it will say "Disassembler Installed". Once loaded you will have an MFS ONLY AWARE environment, but the HD20 INIT evidently tells the Mac all about ANY 800K disk attached to it. That's right, this not only works with the recommended drives but also the original 800K External Drive (M0131) and any 800K drive mechanism (but you will not be able to boot from any but the recommended drives, just like with an HD20 Hard Drive). Just pop a blank 800K disk into any 800K drive and choose Initialize from the dialogue box and you'll soon have a newly formatted 800K MFS disk. Just for the record, I used version 1.1 of the HD20 INIT. As it turns out, I was using my 512K, not my 128K and have been using exclusively early Systems & Finders recently. Somehow I had inadvertently gotten my disks mixed up and accidentally copied the HD20 INIT to the MODIFIED (see below) 2.0/4.1 disk without realizing it and had been using that system with an HD20 Init, which was the last thing I would have ever expected to work as it does. So when I was happily initializing 800K MFS disks with it, I just assumed Pina had been right all along. Only when I retraced my steps did I discover the "Disassembler Installed" startup screen which I had never seen before (well once long ago, but I knew I did not presently have a copy of MacsBug to install – anybody got one?).
Now for the dropping of the other shoe: the HD20 INIT will still not load on the 128K Mac (at least with v1.1 & S2.0/F4.1). But all is not lost. Referring back to the numerous misleading, erroneous and poorly detailed tutorials on formatting an 800K MFS disk, this one caught my eye on Google's comp.sys.mac digest. Declan A. Rieb indicates that once you've formatted and 800K MFS disk with 128K ROMS, take the blank 800K MFS formatted disk, write protect it and use it as a master to duplicate more on a 64K ROM system using a copy utility like SUM's Quick Copy (precursor to Norton Utilities). Well I tested it with Copy II 7.0 and was able to make a "Sector Copy (WITHOUT FORMATTING)" in about the same time as initializing using the Mac's initialization package. It made a perfectly usable and bootable MFS 800K blank disk copy from an unformatted disk out of the box (I should also try the Mac 128K Copy Utility). One note here, if the disk copy utility formats the disk, it may not work and you'll see the same crashes as with trying to format with the Mac's initialization package. While this is not the preferred method for initializing new disks on the 128K, it ain't bad! As I said earlier, once the disk is formatted with 800K you can erase it all you want. The disk retains the 800K formatting instructions, in much the same way as my SCSI ZIP 100 drive retains the 4.2 driver after formatting under System 6.0.4 and will boot from System .97/Finder 1.0 up on my Mac Plus, regardless of how many times I erase it with the Finder.
I hope this proves as interesting for you as it did for me. Now, before we go spreading the results all over the web, it would be great if members on this forum could check the procedures on their own Macs as well as some additional testing I was unable to quickly do. I do intend to continue in my efforts to combine different Systems and Finders to see if there is a way to initialize an 800K MFS disk using just the Finder, though I suspect the above solution is the bit Pina forgot to include in his book. You'll note earlier I didn't try any system 3.0 combinations, though that's worth a stab. I also want to experiment with other drive combinations as well.
Happy MFS-ing!
PLEASE NOTE: The stock System 2.1/Finder 4.1 may NOT work as described by JDW below. Please see my subsequent post in which it was discovered the System 2.1/Finder 4.1 I used above had been modified with the 3.2/5/3 Printer Installer (v1.1) AT ImageWriter (v2.3) ONLY . While This procedure absolutely works, stay tuned for the missing piece to the puzzle, so that you can do it too.
A little history, Larry Pina mentions in his book "Macintosh Repair & Upgrade Secrets" on page 192 that a 128K with an 800K internal drive works just fine, giving you 800K of MFS storage. However, as I've criticized Pina before, he briefly mentions something ground breaking in passing, but gives few details, leaving the reader to infer that there's little else to it. Indeed, I stumbled on the solution accidentally and just assumed everything was working like Pina indicated. Then when I tried to repeat my success, suddenly the thing didn't work. This then is the result of backtracking through my original efforts and what I know know to be true.
ONE WORD OF CAUTION before you proceed. This is not yet etched in stone. The following procedures worked on my equipment and due to some fluke of hardware, may not be repeatable on other equipment. No one should assume this is a universal solution until it has been confirmed by others on this list.
First something I know to be true of both the Macintosh 128K and 512K. As Pina indicates, both of these Macs will boot from an internal 800K drive as long as it is Apple part number 661-0345 (Sony p/n MFD-51W-03), no other earlier drive mechanism will work (though possibly some later models). These drives will also read and write 800K MFS only disks. The Apple 3.5" Drive (Apple p/n A9M0106) which contains the afore mentioned drive mechanism, will also boot, read and write 800K MFS. However, the original Apple 800K External Drive (Apple p/n M0131) will not work without the HD20 INIT and then only to read and write pre-formatted 800K MFS disks as well as HFS) and you cannot boot from this drive with 64K ROMs.
Now for the rub. What Pina does not go into, is how exactly you get 800K MFS disks from which to read/write and boot on a 128K. And perhaps there's a good reason for that. Using System .97/Finder 1.0, S2.0/F4.1, S4.1/F5.5, I was unable to get a 128K or 512K to initialize/format an 800K MFS disk in either the internal or external drive. As JDW pointed out earlier, using the HD20 on the 512K only results in formatting an HFS 800K disk, which is unreadable without the HD20 INIT. So I settled for formatting a 400K MFS Single Sided disk both with the HD20 INIT and in a 400K external drive. Unfortunately, though readable in the 800K drives, any attempts to erase them as 800K MFS resulted in failures or system crashes without the HD20 INIT. The same thing happened with HFS formatted 800K disks (I did not try 400K HFS). So how do you do it?
One method that has been posted around the net, though does not specifically say so, requires a Mac Plus or 128K ROMS. Basically you boot up with a stock System 2.0/Finder 4.1 or earlier (the last MFS only System & Finder and pre-HFS aware), the MacPlus does not care about the HD20 INIT or need any other modifications to the basic system. For my purposes I used exclusively a MODIFIED (see below) 2.0/4.1 and everything that follows is based on that unless stated otherwise. Boot up with this system on a Mac Plus or 512Ke, possibly even a 128Ke (128K ROMs in a 128K Mac – not tested) and insert a blank 800K disk. If it is unformatted the Mac will ask you if you want to initialize and about :30 later, you'll have an 800K MFS disk. Even if the disk is formatted, Erase will accomplish the same thing. The resulting disk will work just fine in a stock 128K and 512K using one of the appropriate 800K drives.
Now you're asking the same question I was: so what good does that do me if I have 64K ROMs? Since you have to have 128K ROMs or the HD20 INIT to format in an 800K drive and the HD20 INIT will only let you format HFS, you're stuck right? WRONG. You're going to love the solution. The HD20 INIT was released with System 2.1/Finder 5.0 (the FIRST HFS aware System & Finder as far as I know) along with the HD20 Hard Drive. The Mac Plus with 800K drives quickly followed with 3.0/5.1 and that quickly followed by a succession of updates resulting in what is the widely accepted stable system 3.2/5.3 which Pina and others reference for use with the HD20 & 800K drives. The reason the MODIFIED (see below) 2.0/4.1 trick works on the Plus & 512Ke is that the System & Finder don't know about HFS, so I suspect the ROM translates the 800K driver info for it and then the Finder acknowledges 800K capacity, but it still only understands MFS. Once the disk is formatted with the disk capacity information, the Finder no longer needs the ROM to translate and any Finder will happily see the disk as 800K MFS. Now what?
Now, put a copy of the HD20 INIT on System 2.0/4.1 (and possibly earlier) MODIFIED with the S3.2/F5.3 Printer Installer (v1.1) AT ImageWriter (v2.3) ONLY (see below). Yup! When the system boots instead of "Hard Disk 20 Startup", it will say "Disassembler Installed". Once loaded you will have an MFS ONLY AWARE environment, but the HD20 INIT evidently tells the Mac all about ANY 800K disk attached to it. That's right, this not only works with the recommended drives but also the original 800K External Drive (M0131) and any 800K drive mechanism (but you will not be able to boot from any but the recommended drives, just like with an HD20 Hard Drive). Just pop a blank 800K disk into any 800K drive and choose Initialize from the dialogue box and you'll soon have a newly formatted 800K MFS disk. Just for the record, I used version 1.1 of the HD20 INIT. As it turns out, I was using my 512K, not my 128K and have been using exclusively early Systems & Finders recently. Somehow I had inadvertently gotten my disks mixed up and accidentally copied the HD20 INIT to the MODIFIED (see below) 2.0/4.1 disk without realizing it and had been using that system with an HD20 Init, which was the last thing I would have ever expected to work as it does. So when I was happily initializing 800K MFS disks with it, I just assumed Pina had been right all along. Only when I retraced my steps did I discover the "Disassembler Installed" startup screen which I had never seen before (well once long ago, but I knew I did not presently have a copy of MacsBug to install – anybody got one?).
Now for the dropping of the other shoe: the HD20 INIT will still not load on the 128K Mac (at least with v1.1 & S2.0/F4.1). But all is not lost. Referring back to the numerous misleading, erroneous and poorly detailed tutorials on formatting an 800K MFS disk, this one caught my eye on Google's comp.sys.mac digest. Declan A. Rieb indicates that once you've formatted and 800K MFS disk with 128K ROMS, take the blank 800K MFS formatted disk, write protect it and use it as a master to duplicate more on a 64K ROM system using a copy utility like SUM's Quick Copy (precursor to Norton Utilities). Well I tested it with Copy II 7.0 and was able to make a "Sector Copy (WITHOUT FORMATTING)" in about the same time as initializing using the Mac's initialization package. It made a perfectly usable and bootable MFS 800K blank disk copy from an unformatted disk out of the box (I should also try the Mac 128K Copy Utility). One note here, if the disk copy utility formats the disk, it may not work and you'll see the same crashes as with trying to format with the Mac's initialization package. While this is not the preferred method for initializing new disks on the 128K, it ain't bad! As I said earlier, once the disk is formatted with 800K you can erase it all you want. The disk retains the 800K formatting instructions, in much the same way as my SCSI ZIP 100 drive retains the 4.2 driver after formatting under System 6.0.4 and will boot from System .97/Finder 1.0 up on my Mac Plus, regardless of how many times I erase it with the Finder.
I hope this proves as interesting for you as it did for me. Now, before we go spreading the results all over the web, it would be great if members on this forum could check the procedures on their own Macs as well as some additional testing I was unable to quickly do. I do intend to continue in my efforts to combine different Systems and Finders to see if there is a way to initialize an 800K MFS disk using just the Finder, though I suspect the above solution is the bit Pina forgot to include in his book. You'll note earlier I didn't try any system 3.0 combinations, though that's worth a stab. I also want to experiment with other drive combinations as well.
Happy MFS-ing!
PLEASE NOTE: The stock System 2.1/Finder 4.1 may NOT work as described by JDW below. Please see my subsequent post in which it was discovered the System 2.1/Finder 4.1 I used above had been modified with the 3.2/5/3 Printer Installer (v1.1) AT ImageWriter (v2.3) ONLY . While This procedure absolutely works, stay tuned for the missing piece to the puzzle, so that you can do it too.
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