THE HOME COMPUTER market can atbest be described as fickle, and at worst,
non-existent. There really isn't much you
can do with a computer in the home; true,
there are lots of potential applications, but
in practice they are either too much trouble, too inflexible or require specialisedinterfaces which are not available. Perhaps
the major spur to the growth of the homecomputer market will be the eventual
availability of information utilities designed to take advantage of home computers (unlike Viatel, which is designed formodified domestic television sets).
Nevertheless, it was the home market
which IBM addressed with the jr. Neverreleased in Australia. this machine clogged the distribution channels immediately
after its release, stubbornly refusing tomove off retailers' shelves. This could be
attributed to several factors: first, the perfectly disastrous rubber-membranekeyboard with 'chicle' keys; second, extremely limited memory expansion; andthird, confused positioning.
IBM's research had shown a surprisingly
large n umber of 'corporate' PCs were being
taken home at least once a week. There wastherefore an opportunity to sell more hardware: either a portable PC which would beeasier to take home, or a second. low-cost
PC which could be left at home andperhaps do double duty as a games
machine.
Typically, IBM pursued both strategies,
perhaps confusing the marketplace. Certainly, many jrs are in use as home compu

I SSCHOOL

TjE
The PC 1r, IBM's firstattack on the UnitedStates' home computer
market, was far from an
unqualified success. HereLes Bell evaluates the IX
the company's second
assault, planned toinfiltrate homes throughthe education system.

ters. and some — but only a few — areused as home workstations to complement the office machine. The educational
market in the United States hasn't leapt toembrace the machine either, despite fixes
for all the machine's problems, combinedwith aggressive pricing.
It is in this climate that Big Blue has
released a new home/education computerin Australia. and no doubt the parent company is viewing Australia as a test market
for this product.
The IX is squarely aimed at the education market, with a spin-off in the homemarket. IBM is supporting the machinewith plenty of educational software, andno doubt games and other software willappear in due course.

First Impressions
The IX is physically quite different from thePC and AT. It is smaller (405 by 290 by 90mm) and finished in a dark-grey colour.
The cabinet consists of a metal tray withplastic facias at front and rear, throughw
nehcitcohrsthperodtirsukde
drives, switches and conThe front panel is dominated by the two
9 cm disk drives, and below them the two
cartridge slots. To the left of centre in thebottom half of the front panel is the window for the infra-red keyboard link, and at
the far left is the on-off switch.
The rear of the machine has numerous
connectors for peripherals. From left toright, they are: lightpen, cassette recorder,audio, printer, joysticks I and 2, optional IP.

IBM'S SCHOOL TIE

RS232C card, display and keyboard.
Two keyboards are available, with either
79 or 98 keys; the larger one has an additional numeric keypad and duplicate Altand Fn keys. The keyboard layout is sensible, with a large Return key and Shift keys
in the right positions. The function keyslabelled PFI to PFIO, rather than FI to F10,
are across the top of the keyboard. Programs like Flight Simulator will need a newfunction key layout — but then, they'll
need to be rewritten for the IX anyway.
The keyboard is much lighter than thePC's, and has a light keyboard action with aconventional feel. What's unconventional
about the keyboard is its infra-red link tothe system unit; there is no need for a
keyboard cable, although one is available
as an option. The keyboard only works
when it is in line of sight with the system
unit; if the the unit is some distance backfrom the edge of a desk, this means you
can't use the keyboard on your lap. However, the keyboard will work over a considerable angle and distance ; 1 was able to place
the IX on a bench across the office andoperate it from the keyboard on my desk.
Of course, 1 have 20/20 vision and knew
what was on the screen anyway; others
may find the principal 'benefit' of thekeyboard is that they can sit sufficiently far
away from the IX that they can't read thescreen .
The keyboard is battery-operated, but if
the batteries run down, the cable will
supply power* Likewise, if two keyboards
are operated in the same room, at least
one must be using the cable, otherwise theinfra-red links will interfere with eachotherDisplay
The display supplied with our evaluation
machine was driven by the RGB output of

the IX, and provided comparable quality to
the Princeton monitor we use on the PC.
The colours were reasonably pure, withcrisp edges, although the saturation was
not as high as on the Princeton. Ironically,
the area where the monitor falls down is insound generation; the speaker is inside
the PC, and the volume control on the frontof the unit seems to control the timbre
more than the volume. The placement of
the speaker in the display monitor restricts
the kinds of monitors which can be used.
Options
The major option for the IX is the expansion unit which sits on top of it. This carries
four general-purpose expansion slots anda 13 cm disk drive, allowing access to jr andPC software on 'conventional' diskettes.
The expansion box also has a blank position for another 9 cm floppy disk drive, andthere is provision in the software for a harddisk, but no indication of where the harddisk fits. Perhaps a 9 cm hard disk drive ison the cards?
The JX's Logic
The IX is based on the same 8088 microprocessor as the PC, running at the samespeed, 4.77 MHz. Memory starts at 64
Kbytes and is expandable to 512 Kbytes,
with 64 Kbyte, I 28 Kbyte, 256 Kbyte and384 Kbyte RAM cards (a time-of-day clockis included on the two larger cards). At thisstage, it appears unlikely any USmanufactured multi-function cards will beavailable for the unit, restricting purchasers to the IBM cards, Perhaps there's anopening for a local manufacturer here?
The memory map of the IX follows thatof the jr; there is no separate colour
graphics adaptor, so 64 Kbytes of systemmemory are taken up with the video display. However, the video circuitry maps

Table 1.
Stage 1

Stage 2

Stage 3Total

Machine/drives

246.38BMARK
246.01
BMARK
206.41BMARK
Interface Age Benchmark 9Interface Age Benchmark 9
Sieve of Eratosthenes
Sieve of Eratosthenes
Disk File Create
Disk File Create
Disk File Create

287.17292.28276.26338.79346.70
329.28875.19884.75811.95851.96861 57
1957,39
1953.53
27.49
29.69
26.99

IX / 9 cm
IX / 13 cm
PC / 13 cm
1X
PCIX
PC
IX. / 9 cm
IX/ 13 cm
PCBenchmark

this area to B8000, just like the bigger
machines, so software will continue towork.
Similarly, the 1/0 ports of the machine
generally conform to the jr map. However,the IX makes extensive use of custom
chips (there are five custom gate arrays),
one of which looks after memory and 1/0address decoding, and this circuit allows
the programmer to change the addressesof the memory banks and I/O ports undersoftware control. Potentially, this makes
the IX a completely 'soft' machine; if apiece of software requires the soundgenerator chip at a different address, theprogrammer could simply move it there. Inpractice, this is likely to be less useful.
With 64 Kbytes of memory, the IX is able
to display colour graphics at higher resolution than the PC. In particular, at 640 by
200 resolution, the IX can display four colours, while the PC is reduced tomonochrome. That's the limit on resolution, however, and I certainly wouldn't
advocate the IX as a CAD/CAM machine.
The major benefit is for educational software, where diagrams can be detailed yet
use colour for emphasis.
Performance
We performed our standard benchmarkson the IX with one major goal in mind: todiscover the difference in performance between the older 13 cm disk drives and thenew 9 cm type. At the same time, we expected to discover some other small differences from the PC, due to the BASIC interpreter being a bit different, different video
memory management and other minorvariations.
We discovered the 9 cm drives on the IX
are slightly faster than the 13 cm drive,
though the difference is not large enoughto be significant. However, neither is quite
as fast as the PC's floppy disk drive —though, again, the disparity is not thatlarge. The figures are summarised in Table
I. together with the standard PC's results
for comparison.
Another important benchmark thesedays is the machine's ability to run software written for the standard IBM PC. We
tried a few different packages on the IX,
with mixed results Relatively 'plain vanilla' programs such as Wordstar and dBase II
worked with no problems, and we tried theNorton 2.0 utilities and to our surprise
they worked just fine.
However, dBase 111 would not run because of its copy-protection scheme, andwe suspect quite a bit of software falls into ►77IBM'S SCHOOL TIE

ory map are different from that of the PC,
and in particular the disk size is different,
compatibility with PC software is limited.
01 course, programs like Lotus 1-2-3 areavailable in PC jr cartridge form, which will
work on the IX.

this category. Flight Simulator didn't runeither; it would ask us all the questions at
the beginning of the program, but thenlock up the system, accessing all the drives
at the same time.
A variety of software is becoming available in the 9 cm format; IBM has released arange of its software, such as Personal
Writing Assistant and the like. The accentis on educational software: the 9 cm diskette is ideal for use in schools as it isrugged and requires far less special treatment than the larger types.
Advantages
So, what are the advantages of the 1X oversimilar PCs? First, it is compact, requiring
less desk space than a conventional PC,
and its infra-red keyboard link offers some
additional flexibility in desk layout,
Next, its low cost will make it available
to market segments previously beyond
IBM's reach; in particular, this means theeducation market, small businesses(perhaps) and whatever sales IBM can getin the home computer market.
Third. the IX offers a couple of advantages for the educational market. First, it isIBM's 'chosen' and supported machine forthat market. Next, its rugged 9 cm diskettes
are ideal for school use, and the IX will
work on the Cluster Program network,
which IBM is apparently repositioning for
educational use. This makes diskless
an attractive option for schools.
Disadvantages'rhe IX also has a couple of disadvantages.
First and foremost is its limited expanda78

bility: there is only one free slot in a 256
Kbyte machine, and that will have to be
used for a serial port. Any further expansion will require the expansion box, which
optionally adds another two slots.
Related to this complaint is the lack ofPC hardware compatibility. All the niceadd-ons for the PC, like mice, modems,
co-processor boards and others, simply
will not work with the IX — they are physically incompatible.
The IX can have at most 512 Kbytes ofmemory, of which 64 Kbytes is used forvideo RAM, so it can't support programs
and spreadsheets as large as the PC can.
And of course, at present there is no harddisk for the IX, although the indications arethat that will be remedied.
Finally, because its I/O ports and memUnit:
Made by:
Processor:
Clock speed:
RAM:
ROM:
I/O:
Languages:
Keyboard:Display:
Graphics:
Expansion:
Best points:
Worst points:
Extras included:
Price:Who Should Buy?
There are two major groups for whom theIX would be a good choice: first, homeusers who have no plans for major expansion or attaching lots of peripherals;
second, the education market, which isIBM's main target with the machine, andpeople in this area will find lots of attractive features.
IBM is also interested in capturing someof the small business market with thismachine. A two-drive version would probably be adequate for light word processinguse, but for accounting applications —which are of prime importance to small
businesses— a hard disk would be essential, so I wouldn't recommend the IX for
this purpose until one becomes available.
Computer hobbyists with any hardwareinterest would probably find the machine
frustrating because of the lack of expansion capabilities, and would probably bebetter advised to plump for a clone if they
are on a tight budget. Software enthusiasts
might find the machine interesting,although some of the more advanced software tools will not run on it.
In summary, the IX is well conceived andwell executed. it owes more to the jr than
the PC, so its architecture looks a littlestrange to us in Australia. Once we develop
some expertise with it, there may even besome interesting software and hardware
developed locally for it,❑IBM Personal Computer IX
IBM Corp lapan, with a little help from their friends
8088
4.77 MHz
64 Kbytes expandable to 512 Kbytes
96 Kbytes
Two joysticks, sound, parallel printerBASIC, BASIC, BASIC
79-key or 97-key OWERTY with i/r link
Defaults to 40 by 25, also has 80 by 25640 by 200, four colours
Limited, but it can be done
9 cm drives; we now have a standard
Limited expansion
Expansion unit, keyboard cable$2115 base (64 Kbytes, no disks), to $3365 for 256
Kbyte two-drive IX3, all including colour monitor