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Setting up the Vulcan hard drive controller on ][GS

dankcomputing

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An interesting thing about the Vulcan hard drive controller + PSU replacement combo for the IIGS is that it actually makes more sense to separate the PSU from the controller! With some creative rewiring, it's possible to put a SCSI drive inside the PSU replacement and run it off a SCSI controller (which will give you access to bigger drives and better performance), and the Vulcan controller itself can then be used in another machine using CompactFlash cards instead of the gigantic first-gen IDE drive it shipped with. Unfortunately, the Vulcan is infamously picky about what drives it accepts, and it takes quite a lot of trial and error to find a CF card that will work. So far I've only gotten two to work - a 32MB and a 64MB, both Viking branded.

On the Drew ][ blog, there's a post about a utility for Linux called part_vulcan that can create a partition map for a Vulcan hard drive controller. I've tried to mirror what was done to run the utility in the blog post as closely as possible. I used what I'm reasonably sure is the the same Linux Live CD, compiled the program and ran it on several CF cards. The partitions created on the cards will show up in the boot menu of the Vulcan, but when I try to run the Partition Manager program on the install disk in order to format them I get the usual "COULD NOT READ VALID PARTITION BLOCK. PRESS 'Y' TO CREATE NEW ONE." error with it failing when I press 'Y'. The ROM on my Vulcan card is the Vulcan Gold ROM (2.0) and the Partition Manager version is 2.04, both of which are the last versions known.

Has anyone sucessfully managed to get this program to work? I've only gotten certain 32MB and 64MB cards to work on the Vulcan, but I've noticed that it's possible to dump a .DD (in my case using WinHex) image of a card that has been formatted successfully and restore it onto a card that does not format successfully using the Vulcan utilities and it will work. Ideally, it should be possible to generate images of successfully formatted cards of any size.
 
I got it to work, but the procedure was bizarre and very glitchy. After partitioning the card from Linux, you have to go into the Vulcan's boot menu and not pick not "boot from slot" but "select boot partition" and pick a partition on the card to boot from. The Vulcan will sometimes switch back to booting from the next slot if there's nothing on the partition, but it's not guaranteed; often it just crashes. If the first partition doesn't work, try the next; sometimes picking a non-existent partition will work. Some CF cards won't even work with this procedure. Instead of booting the setup disk normally (it has GS/OS on it) I elected to boot ProDOS 8 and ran PART.MANAGER from there (which seems to make it more stable). If all is successful it'll display the interleave prompt mentioned on the blog post and you can set up the partitions.

The absolute maximum size for a drive is 512MB with 16 partitions but it's not terribly practical; you can only have 4 active partitions with a hard upper limit of 32MB, even if you use HFS. This forces you to keep going back into PART.MANAGER and swapping the active partitions around, which isn't too convenient as that means you have to hard reboot on every change (program won't even let you quit). 128MB with 4 ProDOS partitions is probably the sweet spot.

I have found that it's possible to take an image of a successfully formatted CF card and restore it onto a CF card that won't format no matter what and it'll work.
 
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I’ve seen 1gb CFs used but only 512mb was visible.
Not allowing partitions larger than 32mb isn’t surprising as there was no HFS FST when the Vulcan came out. By that time I think AE was in decline and wouldn’t have spent to rewrite the Partition Manager. Also probably not much need as the drives they sold weren’t big enough to need HFS.
They did advertise a 200mb Vulcan in their catalog but I never saw one in any of their magazine ads so it could be vaporware. If it exists its ROM and Partition Manager would open up some possibilities
 
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