Amiga 1000 (was:My Recent find)

From: Doug Spence <ds_spenc_at_alcor.concordia.ca>
Date: Sat Nov 1 03:48:09 1997

On Fri, 31 Oct 1997, Bruce James wrote:

> and my latest find a Amiga 1000 with 1080 moniter and 512k memory
> anyone have more information on expansion of this computer??

I used an Amiga 1000 as my primary computer for six years. Beautiful
machine. The darling of my collection. :)

For expandability - it depends on what kind of expansion you mean.
There's the 86-pin edge connector on the right hand side of the machine
which is almost identical to the one on left side of the Amiga 500, and
most devices that will plug into an Amiga 500 will plug into the A1000
facing backward. This sometimes gets things in the way of the joystick or
mouse ports, though, and usually requires some kind of physical support
under the device.

There were a lot of external expansion devices designed specifically for
the A1000, but these seem to be fairly hard to find. A friend of mine has
a large external hard drive box for the A1000, that allows auto-booting by
somehow storing the Kickstart image on the HD. Another friend of mine has
a 2-slot Zorro II bus box for the A1000, that allows use of many boards
intended for the A2000. I've got an A1060 SideCar, which gives the A1000
PC/XT compatability through hardware, and three 8-bit ISA slots. I use it
mostly to control my A1000's hard drive, though, as I couldn't find a
cheap SCSI controller for the A1000 when I was looking for one. (I didn't
yet know of the compatability with A500 devices.)

There were some popular internal memory expansion devices for the A1000,
like the Insider memory board that, IIRC, provided up to 1.5MB. Without
major modification, the A1000 can be expanded up to 8.5MB. (512K of Chip
RAM, 8MB Fast RAM.)

There's a problem with noise on the A1000's external expansion bus, which
I think pops up if you try to plug more than one or two devices into the
bus. I forget what the fix is. Grounding the daughterboard and changing
some PALs? I never ran into the problem so I never really looked at the
solution. :)

The two major limitations of the A1000 are its 256K WCS board that can
only accept Kickstart versions up to 1.3, and the old Agnus that can't be
replaced with a more modern version. Kickstart ROMs can be installed with
a board from DKB called KwikStart II (or similar) which still allows
disk-based Kickstarts to be loaded. ROMs can also be soldered
to the motherboard beneath the floppy drive, but I wouldn't recommend it.
One of the coolest things about the A1000 is the disk-based Kickstarts,
IMHO. :)

The chipset limitation is more serious and more expensive to overcome.
There was at least one board, The Rejuvinator, that allowed installation
of the Enhanced Chip Set (ECS) and I think the Kickstart ROMs at the same
time. There was also a replacement motherboard, called the Phoenix Board,
that allowed the 2MB Agnus to be installed, as well as Kickstart ROMs, 8MB
Fast RAM, and math coprocessor. It also sported a SCSI port, real-time
clock, and a few more minor goodies, but I'm not sure if it's still really
an Amiga 1000 if you replace the motherboard. :)

You should also be aware that the serial and parallel ports on the back of
the A1000 are non-standard. I *think* a gender-changer is enough to use
the serial port safely, but I'm not sure (I used to use standard cabling
and a null modem for transferring files between my A1200 and A1000 with no
problems, and I've used the A1000's serial cable for telecommunications
with my TeleVideo TPC-I). The parallel port, though, requires some
modification to the cabling for safe use. It supplies power on pin 23,
and pin 25 is a reset line.

There were 68020 accelerators made specifically for the A1000. I think
there were also some 68030 accelerators. These theoretically should allow
RAM expansion far beyond the 8MB limit of the stock A1000, but I don't
know if any did allow more than that. None of those boards would use
SIMMs, and back then 2-4MB seemed to be adequate for most "power users".

Anyway, if you need more specific information on anything, I can pull out
my old manuals and magazines and see what I can dig up. Hopefully I
haven't made any errors above. :)

> Bruce James
> ejames_at_newwave.net

Doug Spence
ds_spenc_at_alcor.concordia.ca
Received on Sat Nov 01 1997 - 03:48:09 GMT