Zip Drives & The Amiga



Everything you ever
wanted to know
about the Zip drive
on the Amiga!

Amiga FAQ
Amiga Formatting
Amiga Software
BeBox Formatting


What is
an RDB?
RDB stands for Rigid Disk Block. A RDB is a pre-allocated set of blocks which are reserved on the disk and serve to tell the system about the device and it's partitions. Most modern Amiga hard drive controllers support RDB, and scan for these blocks at boot-time. Once found, they configure the disk according to the information stored on the RDB and mount any partitions it's supposed to (again, according to the RDB).

Mountlists are similar to RDBs, except that they are not automatically scanned for by the controller. Mountlists are text files which contain most of the same information as RDBs do to describe a device and it's partitions, and are used in conjunction with the AmigaDOS command "mount". Under Workbench 2.1 and above, you can find mountlists for various devices (like PC floppies) in the SYS:Devs/DOSDrivers directory.

Whether or not to use RDBs or mountlists for your Zip disks is somewhat up to the individual. If your controller doesn't support automounting via RDBs, then you obviously must use mountlists. At the same time, if your controller DOES support RDBs, you might want to still use mountlists instead of or in addition to the RDB. With RDBs, the disk information is read at boot-time, which means that in order for your Zip disk to be recognized, you must boot with a Zip disk in the drive. Mountlists, on the other hand, allow you to mount a disk after the system is already up, allowing you to not necessarily have to keep a disk in the drive at boot time.

It is worth checking out the software section for "SCSIMounter" which allows you to compromise; It's a little mounting tool that lets you mount devices based on their RDBs after the system has already booted. It also alows you to un-mount and re-mount the same device, which would allow you to use Zip disks with different physical characteristics (partition setups, sizes, etc) without having to reboot.


Which
is better?
That topic is up for much debate, and I can only give my personal opinions on the subject, although you might also check out C|Net's comparison of the two drives.

I hate SyQuest drives and their technology. The EZ drive is basically a smaller version of their larger SyQuest drives; They still use rigid disks in hard plastic casings, and have all of the same frailties of the SyQuest format; If you drop a disk on a hard surface from more than a couple of feet, it's likely all over for that disk.

Yes, the SyQuest drive is faster. Yes, you can put 35-ish more megs on it and the media is just about the same price. But a little extra speed and 35 megs difference is personally not worth it to me, and I refuse to give my money to a company who throws out a hacked-together product in the name of competition. They didn't attempt improve anything over the SyQuest format with the EZ drive, including the awkward disk eject method. The only thing they did with the EZ was make it small.

Personally SyQuest drives make me angry and I hope are on their way out of phase to better technology. We have a 200MB SyQuest drive at work which reads/writes to 200MB disks fine, but reads/writes to smaller SyQuest disks at less than floppy-disk speed. Yea, it's backward compatible as they tout so heavily, but it's nearly useless. On a PowerMAC, it takes over 10 minutes to copy 20 megs of data to a 44MB SyQuest. (Note: The EZ drive isn't backward compatible with anything; It cannot read/write to other SyQuest media which are physically larger.)

So, there. Soap-box Mode Off.


Parallel
or SCSI?

NO, you cannot use the Parallel port version of the Zip Drive on your Amiga!

The parallel port on the Amiga is different, hardware wise, from a PC parallel port, and is incompatible. Besides that, it's a waste of time and speed.

I have heard reports that there is an IDE version of the Zip drive to be released soon. but I haven't seen them and have no idea if they will work on Amigas equipped with IDE controllers, although I don't see why such a device wouldn't.


What do I
need to Zip?
You need:
  • A SCSI controller - Amiga 3000's have built in SCSI controllers - Must have a DB25 connector for hooking up the drive. Most controllers do; If yours doesn't, you can still use a ZIP drive, but will need a special cable. Consult the manufacturer of your controller; It's "beyond the scope of this manual".
  • SCSI device ID 5 or ID 6 must not be in use - the ZIP drive can only be toggled as either ID 5 or ID 6.


Where do I get
Amiga software?
First, you don't need any special drivers on the Amiga to use just about any SCSI device. The Amiga employs something called a Rigid Disk Block, or RDB for short, which is a standard, set-aside area on your hard drive which contains information about all of the partitions on it. When you boot your system, it reads this RDB and automatically configures and mounts whatever partitions you have.

The same is true for ZIP disks. You simply need to get a program like Commodore's HDToolBox to partition your ZIP disks and write an RDB onto them. If you are using a non-Commodore controller, chances are it came with similar partitioning and setup software. See the formatting section for more information.

About the only thing you do miss is the provided IOMega software for locking/password protecting Zip disks. However, some other companies have made the Amiga equivilant of the Zip Tools software, like the Squirrel Zip Tools package. If you need the ability to lock/password protect disks, there is also a no-frills PD program to do it.


Can I format the
Zip Tools disk?
This topic is up for some debate. The disk they provide you is something called Zip Tools which, if you are a Mac or a PC user, is has a bunch of software on it to lock/unlock/password protect Zip disks, as well as some catalogging software and backup software. It's of no use to an Amiga user.

However, the Zip Tools disk comes LOCKED, or in a read only mode. While I had no problems formatting the drive on my Amiga 3000, other users are reporting errors when trying to format it as a result of the disk being locked. Some controllers don't care, others do. I recently ran into someone with a Zip Tools disk they couldn't format. I took it on my machine and oddly enough, could not format it right off the bat either.

There are two known ways to get around this:


Do I buy Mac or
PC formatted Zip disks?
It doesn't really matter because you're going to format them anyway. Unless you are using CrossDOS and/or CrossMAC and wish to use PC or Mac formatted ZIP disks and it's important that they're already formatted for you, then it makes no difference.


How do I mount PC
formatted Zip disks?
Amiga Workbench comes with CrossDOS (as of version 2.1 and higher, I believe). While it is not the complete version (it does not come with any of the tools the regular version of CrossDOS comes with) it does contain the filesystem and device handler.

In order to use a PC disk on the Amiga, you need to make a mountlist entry for it. Try this and see if it works, making note to change the Device and Unit entry to fit your system:

   /*
    * Mountlist entry for CrossDOS filesystem on a 100M ZIP disk
    */

   FileSystem        = L:CrossDOSFileSystem
   Flags             = 0
   Surfaces          = 1
   BlocksPerTrack    = 1
   SectorsPerBlock   = 1
   SectorSize        = 512
   Mask              = 0x7ffffffe
   MaxTransfer       = 0x100000
   Reserved          = 0
   Interleave        = 0
   LowCyl            = 0
   HighCyl           = 196607
   Buffers           = 5
   BufMemType        = 0
   StackSize         = 2000
   Priority          = 10
   GlobVec           = -1
   DosType           = 0x4d534800
   Device            = scsi.device
   Unit              = 5

/* End of mountlist entry
 */

I have not personally tested this mountlist on a PC Zip disk but am told it works. There is also a set of mountlist entries for PC and MAC disks available on Aminet called "ZipMount_12.LHA".


Does AmiBack work
with Zip drives?
Sure does. You can either save backups as an AmigaDOS file on a formatted ZIP disk, or write directly to a ZIP disk (note that this destroys everything on the disk). Either method works great.


Does the Zip
work under Emplant?
Several people have emailed me and could not get it to work properly on the Amiga side using the Emplant SCSI device. However, they have also said that it does work under the Mac side of the Emplant.

My only suggestion is to call Utilities Unlimited and ask them why it doesn't work. So far nobody has ever gotten an answer, so don't get your hopes up.


Does AmiBack work
with ShapeShifter?
I can say that from personal experience, yes, the Zip does work under ShapeShifter, either as an AmigaDOS device running ShapeShifter with a harddrive file, or as an actual SCSI disk on the Mac side. I have successfully taken a Mac formatted Zip and gotten it to come alive on a friend's ShapeShifter as a total SCSI disk, as well as formatted a new Zip under ShapeShifter and stuck it in a real Mac.

Reminder: You cannot configure the Zip as a total SCSI device under ShapeShifter unless you have the registered version.







You are vistor
Hit Counter
All pages and images © 1996-1997 Bob Maple (bmaple@burner.com)
IOMega and Zip are registered trademarks of IOMega Corporation.

The small mailbox, yellow document, floppy disk and red checkmark icons are from the BeOS.
I am not affiliated with IOMega; I just think their Zip drives are cool.