I'm starting this column with a paper I wrote about a year ago; followed by the
usual interesting tidbits.
Software and Hardware for the Home Computer
Microprocessors allow the development of the personal (or home) computer. The
important advantages of the microprocessor (compared with traditional computers)
are low cost and small size; the disadvantages are a small word size and slow
processing speed. These factors imply much about the software and hardware
reasonable for the personal computer.
Software
First, literally millions of people wi11 be able to afford a computer of their
own. Few, however, have the background or time needed to write non-trivial
programs, even in a simple language like BASIC. Most will want task-oriented,
rather than procedure-oriented, languages. Non-programmers will want packages,
for tasks like simulations, games, art synthesis, record keeping, and word
processing. These must be simple to use, yet adaptable to a wide range of
activities. A free lance writer, a high school student, and a club newsletter
editor all will need a word processing package for their personal computer; none
may know an end-of-record from a carriage return.
This means software must be highly interactive, very forgiving (both bomb-proof
and bullet-proof), and therefore quite complicated internally. It seams
contradictory at first, but cheaper computers, need more complex software. Low
cost implies more users, which means less sophisticated users. The computer must
do as much of the work as possible, to shift the burden away from the user. For
any person to tell a computer how to do a task, they must either write a
program, write a block of parameters for a program, or have an interactive
dialog with a program. The latter is easier for the user, but harder for the
programmer. Note, too, that interactive programming allows relatively slow,
byte-oriented software; just right for a microprocessor.
There are many different manufacturers of personal computers, since building
them is a relatively low-capital business. The microprocessor has already led to
a quantum leap in the number of computer system manufacturers, in only three
years. Calculators just do one task for three or four user groups. After all,
there aren't that many ways to manipulate numbers. There are many more types of
applications for personal computers, and many more user groups (reporters, stamp
collectors, doctors, artists), supporting .any markets. With all this
proliferation of microprocessors, manufacturers, and markets, writing portable
software will be a real challenge! A standard operating system for each
microprocessor would have helped enormously, but semiconductor houses are just
beginning to discover operating systems. Zilog is one of the few to have a large
programming staff in-house, BASIC (and, to some extent, PL/M) are the only
microcomputer standards right now - a step in the right direction.
New system programming languages would be useful to implement the wide variety
of needed software. Rich operating systems will be vital, functioning out of
sight of must users. The operating system and system programming language must
be integrated, and optimized for writing interactive, task-oriented, bomb-proof
and bullet-proof systems. These should include common functions, such as parsing
user commands and prompting for correct user input, name binding, error
checking, mathematical functions, and input/output operations.
Hardware
Internal memory is also becoming small and cheap. This is fortunate, since large
programs are needed for interactive software. An affordable computer must have
affordable input/ output devices, as well. The home computer might as well plug
into other home appliances. Televisions, stereo, and telephones are obvious
choices. Already, television makers are considering a direct video-input jack,
and the newest audio cassette format has a digital control track; telephone
appliances, such as automatic answering system, are available now. A television,
plus a keyboard, joystick, or light pen, can handle the user interaction needed
by the software. The development of a flat screen TV display (promised by Sharp
in 3 years) will allow a truly portable computer, the size of a large book. The
computer can also add new dimensions of intelligence to home electronic. Smart
TVs could grab a frame from the cable utility, or synthesize video art (not to
mention playing games). Smart stereos could keep a music directory or do audio
synthesis; they already a given track on a tape or record. Smart telephones, as
well as recording messages, could route calls to a different location, or place
calls automatically if a home emergency arises
As computers become home appliance themselves, people will want to connect them
with other appliances. Data is more likely than programs to be transferred
between machines, since programs will likely be executed from read-only memory
for ease of use and proprietary reasons. A telephone connection between home
computers will open a whole new world of games, and other forms of
communication. Standards will be important for direct, audio cassette, or
telephone interchange.
Many tasks require storing data on some secondary medium. Audio tapes work well
enough for small to medium size data files, such as home bookkeeping records, a
paper being written, or the occasional user program. Magnetic bubble memories
will allow further physical size reductions, if they become inexpensive enough.
However, large read-only data base applications (such as encyclopedias or
food/recipe data) will have to wait for video disks, or wideband video cable (as
in the "wired city" concept). Millions of characters of random access read/write
memory will remain too expensive for widespread use in the near future. Also,
large data bases imply a high speed processor and a large address space, both
lacking in the current crop of microprocessors.
Affordable printers will be a major problem, since many applications require
hard copy, Relatively cheap, dot matrix printers (developed for cash registers
and calculators) will be adequate for some tasks, Those needing high quality
hard copy occasionally (such as professional writers) may use a telephone link
to a photo-composer at a service bureau. Typewriter manufacturers may eventually
add digital input models. When personal computers become book-sized, hard copy
will be needed less often, since it will be as easy to carry around the computer
itself and show people the data directly, or transfer it to their computer.
TIDBITS
Microsoft is hiring systems programmer to work on APL, BASIC, COBOL, and FORTRAN
for the 8080, Z-80, 6502, and 8086 as well as operating systems and other
interesting projects. Applicants should have at least a bachelor's degree and a
year of assembly language experience. Contact Paul Allen at (505) 262-1486, or
write to them at 300 San Mateo NE, Albuquerque, NM 87108. Microsoft is the
leader in microcomputer systems programming. I've applied myself, by the way.
New and interesting Magazine: Satellite Communications, 1900 West Yale,
Inglewood, Colo.80110; 14.95/year. Looks fascinating; stuff on teleconferencing,
how to get satellite communications time, CATV articles, launch dates, etc.
The Retail Computer Store is having a magazine sale; 21 issues on sale for 25
cents and 50 cents! Come expand your collection. |