PB170 can't make bootable 400k floppies for a 128k?

[JDW]

One of our 68kMLA members here recently PM'd me about a problem he's been having trying to format 400k floppies for booting on his 128k Mac. He told me the following:

Format it as 400k by choosing 'one-sided' when clicking on Erase Disk under Special menu on System 6. I copied System 2.0 I got from this site http://www.earlymacintosh.org/disk_images.html but it still wont boot. i tried the disk on both the internal floppy drive and the external superdrive on my 128k Mac but i get a '0F0062' error.

System 6.x allows formatting of 400k disks. I know because I've done it on my SE/30. So is there something inherent to the PowerBook 170 that would prevent a 400k disk formatted on that same PB170 from booting on a 128k Mac?

Thanks.

 

[Strimkind]

Sounds odd. Might be a bad disk image. I remember doing a 400k disk image on my 1400c running 8.6. It was able to create the disk image using Disk Utility, but after it was done it was unable to read the disk.

I would try another disk image or re-download the image in question and see if anything changes.

 

[JDW]

Thanks for the tip. One more question... Should he be using Apple's Disk Copy or something else to make a floppy from the image? Or does it matter on a PB170?

 

[Mk.558]

Did you try Shrinkwrap?

I was making backup images of every disk I have such as important ones, like the System 6 Emergency Network Access Disk. Shrinkwrap would image it fine, but Disk Copy would fail to copy it properly.

I also found my SE/30 didn't like the 7.5NAD produced by Apple by the $ dd command. Makes backup and recovery hairy, as OS X adds things to a floppy like .Trash and other non-target relevant data which robs space.

 

[Mac128]

How else would you make a floppy from a disk image to a disk without Disk Copy? He should be using version 4.2. I presume he is following all the other instructions on Eric Rassmusen's excellent site where he got the disk image. I know for a fact there is nothing wrong with his images. Assuming he is running System 6.x, using an 800K disk and Disk Copy 4.2, the 170's SuperDrive should be more than capable of formatting the disk.

One question though, what version of System 6 are you running? My understanding is that the 170 shipped with System 7 and the only version of System 6 which will run on it is J-6.0.7.1, or a hacked version thereof ... In which case that could be causing some unforeseen problems.

viewtopic.php?f=29&t=15289

 

[Mk.558]

Since the target disk image is in a DC 4.2 format, there shouldn't be a reason it shouldn't work.

On the other hand, ShrinkWrap will open many different kinds of images. The .image suffix can be rather ambiguous.

Neither can DC 4.2 mount disk images.

An interesting link to read.

 

[giolicious]

One of our 68kMLA members here recently PM'd me about a problem he's been having trying to format 400k floppies for booting on his 128k Mac. He told me the following:

Format it as 400k by choosing 'one-sided' when clicking on Erase Disk under Special menu on System 6. I copied System 2.0 I got from this site http://www.earlymacintosh.org/disk_images.html but it still wont boot. i tried the disk on both the internal floppy drive and the external superdrive on my 128k Mac but i get a '0F0062' error.

System 6.x allows formatting of 400k disks. I know because I've done it on my SE/30. So is there something inherent to the PowerBook 170 that would prevent a 400k disk formatted on that same PB170 from booting on a 128k Mac?

Thanks.

Thanks JDW for posting it for me. I got it working. Since all of the disk images i downloaded don't seem to be recognized by Disk Copy 4.2, I tried mounting one disk image on mini Vmac and loaded it on Disk Copy 4.2 and saved it as a disk image. I used HFVExplorer to put the saved image in a diskette. Loaded the image using Disk Copy on my PB170 and successfully made a 400k disk. The disk booted fine on my Mac 128K.

I remember reading somewhere that you can format a 1.4mb diskette as a 400k by covering the small square hole at the bottom right corner. I taped it and formatted (one-sided) the disk on my PB170. Tried it on my Mac 128k, 'Initialize' and it worked. I even tried copying the system files and it booted also. I tried this on two new 1.44mb HD diskette i bought the other day and they all worked.

 

[Mk.558]

You mean the left hole when viewed from the front...the right is the write protection, the left is HD detection.

Also, it is not recommended to use 1.44s as 800s.

 

[Mac128]

Just out of curiosity, how did you download the disk image and get it into your 170? It's possible that OS X altered the resource fork during the download, or after you tried to mount it under OS X, so that Disk Copy could not recognize it on the 170. Whereas a freshly created file within OS X retained the necessary ID. In particular, I have found that Images mounted under OS X often do not work properly in a 68K environment. This was a known problem under OS 8, when using Disk Copy 6. While DC could make a perfectly usable 400 or 800K disk, if the disk were mounted under the OS 8 Finder, it would be corrupt for use under 68K Finders.

 

[uniserver]

i was under the impression the 400k and 800k Floppy drives are variable speed, the High Density superdrive uses a fixed speed,

so i would assume that making an 400k disk with an 800k drive would be fine, i've had issues making boot disks with the superdrive in my powermac 7500, for use with my SE, I ended up downloading the images to the zip drive, using scsi zip disk, making boot disks with 800k drive in the se,

 

[Mac128]

Your impression is wrong. All Apple SuperDrives are capable of reading, writing and formatting HD, DD and SD disks at 1.44MB, 800K and/or 400K capacities. Only the OS and disk copy software limit compatibility. Disk Copy 4.2, or 6.x are more than capable of formatting and copying any of these formats, as well as PC and I think even Apple II. Only certain OS versions prevents access to certain formats via the Finder. Since your PM 7500 shipped with OS 7.5.2 (one of the last operating system 800K drive Macs can use), you're going to run into certain limitations making 400/800K disks. And if you are running 7.6 or above, then you are really going to have trouble. Best to stick with System 6 or earlier, or follow the directions closely on the earlymacintosh website, noting the caveats that you should never try to mount a 400/800K disk image or read a 400/800K disk on any OS above 7.5.5! Though I try to avoid System 7 altogether depending As I've had mixed results. And keep in mind 7.5 breaks the ability of the Finder to even format a 400K disk, along with a laundry list of other incompatibilities intoruced with System 7 - so its no wonder this system causes problems.

 

[giolicious]

You mean the left hole when viewed from the front...the right is the write protection, the left is HD detection.
Also, it is not recommended to use 1.44s as 800s.

Yes, not the write protection. Just a temporary solution to start a Mac.

Just out of curiosity, how did you download the disk image and get it into your 170? It's possible that OS X altered the resource fork during the download, or after you tried to mount it under OS X, so that Disk Copy could not recognize it on the 170. Whereas a freshly created file within OS X retained the necessary ID. In particular, I have found that Images mounted under OS X often do not work properly in a 68K environment. This was a known problem under OS 8, when using Disk Copy 6. While DC could make a perfectly usable 400 or 800K disk, if the disk were mounted under the OS 8 Finder, it would be corrupt for use under 68K Finders.

I use a Windows 7 PC and all the disk images i downloaded were from different sources including System 1 - System 3.2. I also use mini Vmac to test those images. The system image I tested is System 2.0, Finder 4.1 which i got from http://www.earlymacintosh.org/disk_images.html. I'm not really sure why DC4.2 cannot recognize this image and the other on both PB170 and mini Vmac. What I did is drag the disk image on DC4.2 under mini Vmac and saved it again as a disk image. I use HFVEXPLORER and a USB Floppy Drive to put the disk image file into a 1.44mb diskette for use on my PB170. Running DC4.2 on both PB170 and miniVmac now recognizes the disk image I saved.

note: I use Stuffit 9 on Windows 7 to extract the images.

 

[Mk.558]

Does anybody know what .image formats are supported by the $ dd command?

If it's just a raw binary duplicate, which is what I believe dd is, then it is a bit puzzling why there are about 10 different types of image files (.dsk, .image which could be many, Shrinkwrap also uses the .image handle).

 

[Mac128]

My guess is Windows is the culprit here. It is likely stripping the resource fork off, or otherwise altering the disk image file so Disk Copy will not recognize it. When you re-save it in mini vMac, Disk Copy is adding back the attributes Windows likely stripped. This is why I try to keep my files in the same environment. When I download disk images, I usually do it inside something like Basilisk II so the image is downloaded into a Mac OS of similar vintage, then copy the disk image into a mounted disk image which I can then transfer via zip to any other Mac. Direct transfers to a 128K and 512K are achieved via Mac Terminal and null modem within the same emulator.

But good work around! Thanks for the tip.

 

[uniserver]

@mac128

(don't be rude)

here is what i said

Re: PB170 can't make bootable 400k floppies for a 128k?

by uniserver » 19 Mar 2012, 16:01

i was under the impression the 400k and 800k Floppy drives are variable speed,

---( 100% Correct ) this statement is completely true

the High Density superdrive uses a fixed speed,

--- This is also True in regards to High Density Disks, There must be some

Hardware backwards compatibility that apple has specially included, to properly read and write 400k/800k disks with the superdrive...

so i would assume that making an 400k disk with an 800k drive would be fine,

--- Again 100% true

i've had issues making boot disks with the superdrive in my powermac 7500,

--- True, i have had issues making 800k boot disks with my 7500 powermac

for use with my SE, I ended up downloading the images to the zip drive, using scsi zip disk, making boot disks with 800k drive in the se,

--- again True, i did do this, and it did work...

uniserver

Joined: 12 Dec 2011, 13:51

 

[uniserver]

dd does not care about file extensions, it's a beast, it will start at 0 and continue until the file is written.

here is how i use DD to make a complete copy of the Sco Unix server HD at work

open terminal in mac

- type

- diskutil list

- now you see the 40 gb drive, /dev/disk0 or something like that

- type: sudo su

- dd bs=1m if=/dev/disk0 of=unix.image

- this will take some time you can follow the status of this by typing in ls -l

it will show you the size of unix.image, when it gets to 40 gb wala!

- now, unmount the 40 gig drive

- connect the new IDE drive, in my case it was a western digital blue 320gig 32mb cache

- diskutil list - just to make sure the device has not changed numbers

- dd bs=1m if=unix.image of=/dev/disk0

- you can now open up activity monitor, and click on disk activity and when it counts up to 40gig written +/- it will be complete.

 

[uniserver]

ahh looks like my retained info was correct, with regards to the USB External Floppy drive's, and yes 400k and 800k apple floppy drives were variable speed, 1.4m standard was fixed speed http://siber-sonic.com/mac/newmillfloppy.html'>http://siber-sonic.com/mac/newmillfloppy.html

in farther research the apple super drive will read/write 400k/800k/1.4m http://siber-sonic.com/mac/newmillfloppy.html

not too shabby,

 

[Mac128]

Uniserver, I'm sorry you perceived my succinct reply as being rude. However I did misread your post. I did not follow the rationale behind your comments, and assumed you we're saying SuperDrives could not read and write 400k & 800k disks, hence the reason you transferred your images via zip to your SE (in which case your impression would have been wrong). Since I did not address your other points, aside from trying to explore the reasons why you may be encoutering problems on your 7500, they were never in question. Certainly I myself transfer images from my OS X Mac to my Plus via Zip all the time. My appologies. But thank you for confirming the statements I made in my post with your additional research. Hopefully this will lead to you being able to use your 7500 to format 400/800K disks in the future and eliminate the additional step of transferring to the SE. And thank you for sharing your Zip transfer method for those who also face this problem. While I am always looking to simplify the disk making process, often the least frustrating way is to keep the process in a native environment, even if it requires a little extra work.

 

[giolicious]

My guess is Windows is the culprit here. It is likely stripping the resource fork off, or otherwise altering the disk image file so Disk Copy will not recognize it. When you re-save it in mini vMac, Disk Copy is adding back the attributes Windows likely stripped. This is why I try to keep my files in the same environment. When I download disk images, I usually do it inside something like Basilisk II so the image is downloaded into a Mac OS of similar vintage, then copy the disk image into a mounted disk image which I can then transfer via zip to any other Mac. Direct transfers to a 128K and 512K are achieved via Mac Terminal and null modem within the same emulator.
But good work around! Thanks for the tip.

Yeah I suspected Windows too. I tried downloading and extracting a disk image using System 7 under Basilisk II and DC was able to recognize the image. I'll try it later on my Macbook Air.