Apple IIe SCSI card device support

This is depending to the operating system...
in general, all harddisks up to 330 MB and CD-ROM.....
with special software also SCSI tapedeck for backup...
with special software scanner....

SCSI is a specification. You don't necessarily need an "apple iie compatible" hard drive. Since you're using an apple iie and if you want to use Prodos, then a hard drive with 255MB is pretty much the maximum that you will need. However, to access all of the information on such a drive, it needs to be partitioned and formatted on an apple iigs, since the partitioning program on the original disk for your interface card is limited. If you want other types of partitions for other types of software, then you need a larger hard drive, however I do not know if such a configuration would work.

SCSI is a specification. You don't necessarily need an "apple iie compatible" hard drive.

That's true... in a perfect world. Like a lot of "other" companies (SUN and their hokey "improvements" comes to mind...) Apple did a few things with their software to make sure they only work with their drives (search Apple ROM HD some times.) Luckily that's limited only to their utilities; on board firmware does not particularly cares.

Since you're using an apple iie and if you want to use Prodos, then a hard drive with 255MB is pretty much the maximum that you will need.

Here's what David Empson had to say on the subject some 12 years ago...

Under ProDOS-8, there is an absolute limit to the number of partitions you can access, which varies somewhat depending on which SCSI card you have, which ProDOS-8 version you are running... ProDOS-8 can only access ProDOS-formatted partitions on the hard drive... Here are some of the limits you will run into on the number of partitions.

1. Firmware limits imposed by the card. (These only affect ProDOS-8, not GS/OS.)

- If you have an original Apple SCSI card, you cannot access more than 7 volumes under ProDOS-8 (counting all partitions on all drives connected to the card).
- If you have an Apple High-Speed SCSI card, the corresponding hard limit under ProDOS-8 is a theoretical 110 partitions. (The practical limit is much lower.)
- If you have a RamFast SCSI card, I don't know if there is a fixed upper limit.

2. Limits imposed by ProDOS-8.

- If you are running ProDOS 1.0 or 1.1, you can only access two volumes per slot.
- If you are running ProDOS-8 1.2 through 1.9, you can access two volumes per slot, except in the case of slot 5, where you can access four volumes, provided the card supports this (Apple's SCSI cards do). The additional two drives are mapped to slot 2, but this can only occur if slot 2 does not contain anything which ProDOS-8 regards as a disk controller (including SCSI cards and some types of RAM card).

- If you are running ProDOS-8 2.0 or later, and the card supports the SmartPort firmware interface (both Apple cards do, but the RamFast doesn't), ProDOS can remap additional partitions to unused slots. For the purposes of this remapping, ProDOS regards a slot as used if it contains somethink which looks like a disk controller (same rule as above). If the slot has a single drive (e.g. a RAM card or a floppy disk controller with one drive connected) you cannot use the second unit number. You also need to allow for S3,D2 which is always the /RAM volume (64K RAM disk in auxiliary memory). ProDOS will always access the partitions in ascending order on the drive, until it runs out of available unit numbers. The maximum theoretical limit which can be achieved here is 13 partitions, but that would only be possible if you had no floppy disk controllers.

- The RamFast card has its own mechanism for remapping partitions, which allows you to select active partitions from a menu. It has greater flexibility than the Apple SCSI cards, and may allow you to access more than 13 partitions.

If using the normal Apple II SCSI card ( not the SCSI II or the RAMfast ) a size of 360 MB to maximum of 450 MB will be O.K.
this will give you another 32 MB for UCSD Pascal and a another 32 MB for CPM. But as far as i remember the solutions for formatting that partitions ( UCSD and CPM ) have not been given by Apple Computer Inc. - but there are solutions given by former User Groups in their public Domain Disks... but that will require some search...
nate: as far as i remember there have also been restriction that the UCSD partition must be one of the first 4 partitions and at CPM it is required that the partition must be one of the first 2. So it is recommenend to make first partition ProDOS, second CPM, thisrd UCSD Pascal and then the rest of the partitions again may be ProDOS.
There are existing conversion software disks that enable to access alternating partitions ( so you may read from CPM a ProDOS partition and convert that file before it is stored at the CPM partition. This will permit for example to read Pascalfiles written in ORCA Pascal and then later convert them for use with Pascal MT+ in CPM.
sincerely speedyG

That's true... in a perfect world. Like a lot of "other" companies (SUN and their hokey "improvements" comes to mind...) Apple did a few things with their software to make sure they only work with their drives (search Apple ROM HD some times.) Luckily that's limited only to their utilities; on board firmware does not particularly cares.

It is the firmware that matters. I did mention using the iigs to format a hard drive so the iie can access more partitions. I am aware of the limit on Apple's utilities. That's why I wrote:

...since the partitioning program on the original disk for your interface card is limited..

I have connected different hard drives to my apple ii scsi card. I say all these things because I have the same card that the original poster has.

Here's what David Empson had to say on the subject some 12 years ago...

Under ProDOS-8, there is an absolute limit to the number of partitions you can access, which varies somewhat depending on which SCSI card you have, which ProDOS-8 version you are running... ProDOS-8 can only access ProDOS-formatted partitions on the hard drive... Here are some of the limits you will run into on the number of partitions.

1. Firmware limits imposed by the card. (These only affect ProDOS-8, not GS/OS.)

- If you have an original Apple SCSI card, you cannot access more than 7 volumes under ProDOS-8 (counting all partitions on all drives connected to the card).
- If you have an Apple High-Speed SCSI card, the corresponding hard limit under ProDOS-8 is a theoretical 110 partitions. (The practical limit is much lower.)
- If you have a RamFast SCSI card, I don't know if there is a fixed upper limit.

2. Limits imposed by ProDOS-8.

- If you are running ProDOS 1.0 or 1.1, you can only access two volumes per slot.
- If you are running ProDOS-8 1.2 through 1.9, you can access two volumes per slot, except in the case of slot 5, where you can access four volumes, provided the card supports this (Apple's SCSI cards do). The additional two drives are mapped to slot 2, but this can only occur if slot 2 does not contain anything which ProDOS-8 regards as a disk controller (including SCSI cards and some types of RAM card).

- If you are running ProDOS-8 2.0 or later, and the card supports the SmartPort firmware interface (both Apple cards do, but the RamFast doesn't), ProDOS can remap additional partitions to unused slots. For the purposes of this remapping, ProDOS regards a slot as used if it contains somethink which looks like a disk controller (same rule as above). If the slot has a single drive (e.g. a RAM card or a floppy disk controller with one drive connected) you cannot use the second unit number. You also need to allow for S3,D2 which is always the /RAM volume (64K RAM disk in auxiliary memory). ProDOS will always access the partitions in ascending order on the drive, until it runs out of available unit numbers. The maximum theoretical limit which can be achieved here is 13 partitions, but that would only be possible if you had no floppy disk controllers.

- The RamFast card has its own mechanism for remapping partitions, which allows you to select active partitions from a menu. It has greater flexibility than the Apple SCSI cards, and may allow you to access more than 13 partitions.

Did you read what he said and what the original poster said?

The original poster says he's got an apple II scsi card, not the high speed model. That means, according to David Empson...

"If you have an original Apple II SCSI card, you cannot access more than 7 volumes under ProDOS-8"

That means 7 Prodos partitions. Each prodos partition is limited to 32MB.

32MB multiplied by 8 is 255MB and that's exactly why I said:

Since you're using an apple iie and if you want to use Prodos, then a hard drive with 255MB is pretty much the maximum that you will need.

Remarkable what turns up with a little effort...

"If you have an original Apple II SCSI card, you cannot access more than 7 volumes under ProDOS-8"
That means 7 Prodos partitions. Each prodos partition is limited to 32MB.
32MB multiplied by 8 is 255MB and that's exactly why I said:

Since you're using an apple iie and if you want to use Prodos, then a hard drive with 255MB is pretty much the maximum that you will need.

Remarkable what turns up with a little effort...

Hello insanitor,
nearly complete.... but the poster also asked for use with alternating OS....
and even the old SCSI is able to handle up to 2 partitions of UCSD and 2 partitions of CPM.....
so that are another 4 time 32 MB together assuming to 128 MB additional usable space needed.
But by practical use i had recognized the limitations listed above that require partitions to be below no. 4 ( at least the first one of the alternating OS ) this seems to be result from fact that at least the first partition of alternating OS must be found in "lower number of partitions" due to the missing abilitiy of the firmware to allocate such alternating OS in later partitions demanding to skip more than 4 partitions ahead....

In the mid 80´s we have taken here in Germany in the Pascal User Group in the AUGE ( Apple User Group Europe ) the Utilities disk for the profile and analyzed the filer....
there exists a recompiled version of that filer, that is able to handle 2 partitions within UCSD Pascal
- and that partitions are invisible within proDOS to ProDOS....
and same is valid to CPM..... there is a modified version of the CPM-formatter availiable.... that had been cloned away from the source of the formatter published in a German Computer magazine ( i believe that was from mc or from c`t )
i do know this because i have used it exactly that way ! I programmed with UCSD Pascal... and some of the sources i
have moved to the CPM partition and then after several adjustmants i have recompiled that same sources within Pascal MT+
......
sincerely speedyG

"If you have an original Apple II SCSI card, you cannot access more than 7 volumes under ProDOS-8"
That means 7 Prodos partitions. Each prodos partition is limited to 32MB.
32MB multiplied by 8 is 255MB and that's exactly why I said:

Since you're using an apple iie and if you want to use Prodos, then a hard drive with 255MB is pretty much the maximum that you will need.

Remarkable what turns up with a little effort...

Hello insanitor,
nearly complete.... but the poster also asked for use with alternating OS....

That's why I said...

If you want other types of partitions for other types of software, then you need a larger hard drive, however I do not know if such a configuration would work.

And I said it BEFORE the poster also asked for using the hard drive with an alternate OS.

complete