The Apple /// was introduced in September of 1980 and was Apple's
first computer designed by the company itself, and not by Steve Wozniak and
Steve Jobs. On paper, it looked promising with 128k of RAM, 80 column video
and other enhancements as standard. It could also run CP/M 2.2 when using
the Microsoft Softcard ///, as well as Apple II software under emulation.
The machine had a number of things against it though, the first of which was
the poor design of the case which led to overheating and the chips on the
boards working themselves loose from thier sockets. Apple even went so far
as to suggest that users pick one corner of the machine up 3-4 inches and
then drop it to reseat the chips! Apple eventually fixed this problem in the
exisiting machines and then re-released an improved version as the Apple ///+,
but the damage had already been done to the machine's reputation and it never
gained the momentum needed for it to be successful. Two other things against
this machine were it's high price, since it was geared towards businesses, and
the fact that the enhanced Apple /// features weren't available when running the
machine in Apple II mode. All of this doomed the Apple /// to be Apple's first
big failure, to be followed shortly by the Lisa. Further developement of the
Apple /// and ///+ would be discontinued in April 1984. Though the Apple ///
was a marketing failure, it's operating system, called 'SOS' (Sophisticated
Operating System) provided the base for ProDOS for the Apple IIc, IIe, and IIgs.
The HFS file system on the Macintosh was also based on part of SOS.
SOS was a very sophisticated operating system and some of it's features
include: totally RAM-based; hierarchical file-structure; manages all memory
locations and I/O; will find location of files for you; error proof menu
system; interrupt driven; device-independent I/O; and program execution could
continue during printing. All I/O was done through device drivers, which
were easily rewritten and updated.
Two different style memory boards were used in the Apple ///, which relect the
changes made to it's mainboard. The first style, which has 3 rows of chips, is
the older 12 volt memory board. The newer style, which was available with either
128k or 256k, is plainly labled as the 'AIII 5V Memory' just above and to the right
of the Apple Computer logo on the component side. This is the newer 5 volt board
and will only have 1 row of RAM chips if it is a 128k board, and will be fully
populated with two rows of chips for a 256k board. The two types of boards are not
interchangable without modification to the system mainboard.
This particular Apple /// in my collection includes the standard Apple ///
with 128k of RAM (12V style), Monitor ///, internal 140k floppy drive, external Apple ///
-Disk II, external Disk /// (both external drives daisy-chained together),
Silentype printer, and a Softcard /// installed in one of the expansion slots
for running CP/M 2.0. I also have an Apple Universal Parallel Interface card for this
system. This Apple /// was originally owned by Northwestern University.
Jeff's Computer Haven Home Page