Amiga Computing - Commodore Is Awesome

0
ISSING MMU
I own an Amiga 4000/030 and have been having trouble with running out of RAM
Do you have a problem?
Do you sometimes
find yourself
poised over your
Amiga with axe in
hand, spouting profanity
at the stubborn refusal of your software or
hardware to behave properly?
Well, calm down and swap the axe for pen and paper,
jot down your problems, along with a description of your
Amiga setup, and send it off to Amiga Computing Advice
Service, IDG Media, Media House, Adlington Park,
Macclesfield SKI° 40,P. Alternatively, e-mail us at
AOLS@acomp.demon-muk
l i virtual memory program from a PD house.
w 1 I followed the instructions which said it will work on any Amiga with Workbench
h
--I 2.x and higher, but I just simply cannot get it to work. All I can get it to do is write a
4Mb file to my hard drive and then crash. I hope you can help.
e
James Sergeant Sussex
n
u If things in life were only so simple. Unfortunately, the program instruc-
s tions are lying. To use virtual memory in this way, you have to
i , have a MMU - a memory management unit - fitted to your machine.
n The 030 version of the A4000 is the EC version, so has no MMU, and
therefore, g unfortunately, you will not be able to get the advantages of virtual
memory. m
y 111111•11' '1111111
s -
o
Au1200
ANSWERS
n
d
the low price of the
. use 3.5 inch drives which are cheaper. The
OverDrives
big draw back is that you will lose your PC
islot, s so you will not be able to use any
other hardware that uses the PC slot.
t h a t
t
In
h
answer
e
to
y
question six, the Amiga
can read any of these CDs but it can only
, sI
am thinking of buying an Al200
a later this year, but there are a num-
m ber of questions I am confused
p
about that I would like answering
before I buy one. I will probably be
l
using the Amiga for scanning and word
processing
e
applications.
r
I. What a is the difference between 2.5 and
3.5 inch n hard drives?
2. Is there d really enough room to fit and
install done
of the above drives inside the
Al200? i
3, Which g do you recommend - internal or
external?
i
4. Does an IDE hard drive mean it is internal?
5. An
t
'Over Drive' hard drive seemed to cost
less and
i
be more convenient, and does not
invalidate
s
the Amiga's warranty by slotting
straight e into the PCMCIA port. Does this
mean rI
cannot use the Squirrel interlace?
6. Using . SCSI CD-ROM drives on the Amiga,
which A CDs can I use? Philips CD-i, CD32 PC
CD-ROMs? f
It would probably have been
easier just to say tell me
s
\
IDE drives and the Amiga! IDE
stands for Integrated Drive Electronics, this
means that e the hard drive interface is built
into the
v
drive. So when it comes to fitting
an IDE drive e all you have to do is connect
it with an r IDE cable.
To answer y your first two questions, 3.5
inch drives t are, surprisingly, an inch wider
and generally h a lot larger than 2.6 inch drives.
They i also have a separate power supply
and nare
quite a bit cheaper, due to
them being g easier to make. The Al 200 was
designed
y
to take a single 2.5 inch hard
drive internally, but it is possible to fa a
o
3.5 inch drive inside an AI200, although it
Is quite
u
a squeeze and you need to get
hold of a k special cable to fit it.
I would n opt for the internal drive, mainly
because oit
does not take up any more desk
space, and w as long as the drive is fitted
by an authorised a dealer you will not
run programs which are written for the
Amiga. Therefore, you may be able to look
at file on a PC CD, but you cannot run any
PC programs.
It is a little difficult to directly compare
AGA to a PC system. HAM modes are
unique to the Amiga and can be thought of
as a pseudo 24-bit display that only
requires 8 bitplanes. Therefore, on a display
basis AGA is equivalent to a 2Mb
SVGA graphics card. Where it loses out is
on screen update. If you try to run a 256
colour screen on anything but a low resolution
screen then AGA starts to show the
strain. If you then try a Db11
3screen
in 256 colours, screen update
41. almost ngrinds o to a halt
fl On i PC c systems k e r the effects of running
higher resolution modes are much less
pronounced, as PC video cards use video
RAM. This allows the screen to be updated
by the computer, as well as being outputted
to the monitor for display. The AGA
chipset can only do one of these at a time,
7. How r good are the graphics of the AGA invalidate b your warranty.
and in high resolution screens, displaying
chipset i compared with PCs?
e
n Andrew, a.m.h.wongt@uclon_acuk
d
The OverDrive o hard drives are actually
IDE mechanisms,
u
so IDE drives do not have
to be fitted
t
internally. The main reason for
the screen takes up so much time that
there are very few clock cycles left for the
screen to be re-drawn.
s
u D QUANDARY
g
g I want to add a CD-ROM to my Al200, but the information I am getting
so.
e
about CO-ROMs seems to be inconsistent. In reading letters about
si
CD-ROMs, people seem to be having quite a bit of trouble getting them up
and running.
tJ
So, my questions are: Do you have recommendations as to brands that
are ecompatible
with my system?; do I have to get drivers, since I have Workbench
of the AmiCDRom handler software - this is public domain, so is readily
available. The installation is very straightforward - you just have to make
sure you pick the right device name for you SCSI interface and that the
CD is set to the right SCSI ID. This is where people can have problems, but you
just have to check in the manual what the device name is for that particular
interface.
3,0, d from the AmiCDRom handler, or would they be included and be able to work If you are starting from scratch then I would recommend the Squirrel option.
on I the Amiga when I purchase a CD-ROM?; would the Squirrel help in connecting You get a proper SCSI interface, and the supplied software is setup to use a CDthe
s CD-ROM up to my system? Any other pertinent information you might have ROM. If you purchase the CD-ROM with the Squirrel you have a ready-to-use
about e CD-ROMs would be quite helpful to me since I am starting at 'ground zero.' solution. Just install the software, which is very straightforward, and away you
n
Michael Wilson, Seattle USA go.
d
Currently, the only real bind with Amiga CD software is CD32 incompatibility.
o I think you have got a little too worried about fitting a CD-ROM to
f
your Amiga. The process should be, and is, very straightforward.
/ Y o u have probably got a little confused from other problem letters
f
in which people are trying to add CD-ROMs to an existing
SCSI
f
board. It you already own a SCSI interface then it is necessary to get hold
o
111•1=11111111M
r
a
The Squirrel comes with CO32 emulation which is pretty good, but can still fail
to run some CD32 games - however, all other Amiga CDs will work fine.
Hopefully, game writers producing CD software will move towards writing
generic Amiga CD titles that simply act like hard drive installed games, but
working from the CD.
AMIGA COMPUTING
FEBRUARY I 99 6