Re: A Few Apple II questions...

[dempson@actrix.gen.nz (David Empson)]

Labelas Enoreth <labelas@hotmail.com> wrote:

> I think the order is AppleDisk3.5-UniDisk3.5-AppleDisk5.25 on the chain,
> so everything should be proper. Can I use two Apple Disks 3.5? _and_ one
> UniDisk 3.5?

Yes.

The absolute theoretical limit (for the IIgs) is any combination of:

- Up to two Apple 3.5 Drives (or equivalent)
- Up to 127 UniDisk 3.5 Drives (or other intelligent "SmartPort" drives)
- Up to two Apple 5.25 Drives (or equivalent)
- RAM disk (/RAM5) and ROM disk (/ROM5)

The SmartPort firmware may have a lower limit on the total number of
drives.  At a guess, I suspect it is limited to something like six
drives.  Note that 5.25" drives are not counted toward this limit, but
Apple 3.5 Drives, the /RAM5 disk and /ROM5 (if present) are counted.

The ProDOS driver firmware allows access to four drives via slot 5
(again, 5.25" drives aren't counted).  I don't know what limit the
SmartPort driver imposes, but this would only affect ProDOS-8 anyway.

Finally there is the question of electrical loading.  I haven't been
able to find an explicit limit, but the general recommendation seems to
be four drives in total connected to the IIgs disk port (physical
drives; don't count /RAM5 or /ROM5).

> > Unfortunately the DB15 connector on the IIc wasn't made to hook directly
> > to anything except the LCD display. For RGB output you need an uncommon
> > external adapter box. It's a pity they didn't make that an RGB port.

[pedantic mode on] It isn't a DB-15, it is a DA-15.  The second letter
refers to the size of the connector: DB is the size of the standard
RS-232 connector (DB-25).  Higher density connectors (more rows and/or
columns of pins) which are the same size retain the letter while
changing the number.  For example, the IIe/IIc/IIgs joystick connector
is a DE-9, while the VGA monitor connector (same physical size but more
pins) is a DE-15. [end pedantry]

> I'd wondered about the IIc's port, though I could have sworn at one point
> I knew someone with an RGB monitor hooked up without any excess
> attachments...maybe I was wrong though. Was the adaptor sort of like the
> IIc RF modulator?

The most common one is a "Video 7" adaptor, if I remember right.  There
are two variants: one supports a digital RGB monitor, while the other
supports analog RGB.

I haven't seen one, but the general idea seems to be a small box which
screws directly into the back of the IIc (on the video expansion
connector), providing another DA-15 connector for the monitor (possibly
a different connector for the digital RGB adaptor).

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand