The Acorn PC

By: logik

Way back in 1988, acorn started producing the archimedes series of desktop
computers. while these werent so successful in the primary business market,
they were very popular in schools. almost any student can recall using one
of these computers at one point of their lives. not so long ago, i happened
to spot an acorn 4000 at school, which had been unused for a long period
of time. being a netbsd user at the time, i went to the site and found that
netbsd/arm26 was being developed for the acorn series.

Upon taking the computer home, i found out that the acorn had no provision
for standard ram expansion (netbsd requires 8mb) and i was left with a piece
of junk. a friend of mine had recently converted a defunct vcr into a fully
working linux box, so i figured that a cross-platform mod would be quite
challenging. the real problem with mods is the powersupply used. lucky for
me, i could convert the acorn powersupply to standard at connectors. the
acorns power supply puts out +5,+12,-12 and ground. it lacks a -5 rail, butthe computer hasnt complained.

The power supply was opened and a set of at connectors and a harddisk plug
were soldered to the voltage pads. the completed product is below:

the converted power supply

Next was the case. the main reason for choosing this case to house a computer
was the fact that it is very slim. this turned out to be a problem as we see.
I turned my attention back to mounting the board. i put the motherboard into
the actual case and used a pencil to mark where the mountings should go. having
done this i drilled holes and threaded them, and the motherboard happened to fit
perfectly :)

The motherboard was screwed in and the backplate removed. an isa riser was found and
the top two slots were (gasp) hacksawed off, so the case could close properly. three
devices were fitted, a 1mb cirrus logic videocard, a sb16 and a noname 10mbit network card. the backplate was replaced, and after a bit of moddage - the cards didnt wobble again.

the front

the modified backplate

The computer now lives its life as a mp3 box, soon to be put into a car. an input device
is still in the concept stage, although some sort of modified mouse could provide basic
player functionality. The actual computer is a pentium 75 @ 90, 16mb ram, 420mb harddisk
and a low power motherboard (acer v55). the whole thing runs freebsd. I am quite sure that
this is the only mod of its type.

inside the acorn

logik (logik@gateway.net.au)

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2.) The 2nd Annual 20 Worst People, Places and Things on the Internet 2001 - Archfiend
3.) NetStat - An overlook at market locked out commands - Kn¿ght
4.) The Acorn PC - logik
5.) The new iMac: Symbolic of what is wrong in technology - Dietcoke
6.) Interview: The Womb - A digital rebirth of sound - L33tdawg
7.) Review: Return to Castle Wolfenstein - L33tdawg
8.) Two years and still kicking - L33tdawg
9.) Of broadband gimmicks and the like - biatch0
10.) The Real McCoy - Dinesh Nair