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Comment:Rewrote the history section at the top of the CC8 manual to give a better arc.
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SHA3-256:694c02765217b1245b500a2031508b8d9e501249ef48ab3912d5fe8ee8f2df97
User & Date: tangent 2019-02-21 09:08:04
Context
2019-02-21
11:55
Many improvements to the CC8 user manual. Basically, I began re-reading it from the top, improving it along the way with my new understanding of CC8. check-in: 0316450b57 user: tangent tags: cc8-octal-output
09:08
Rewrote the history section at the top of the CC8 manual to give a better arc. check-in: 694c027652 user: tangent tags: cc8-octal-output
08:55
Updated the CC8 user manual to cover the new octal output default. check-in: 84f718936e user: tangent tags: cc8-octal-output
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# CC8 Manual


## A Bit of Grounding History

The C language and its derivatives are now the industry standard for the
development of operating systems and utilities. The language has evolved
significantly since its initial specification in 1972.

















The first implementation of C was on the PDP-11 as part of the early
work on the Unix operating system, and it was initially used to write
system utilities that otherwise would have been written in assembly. A C
language compiler first appeared publicly in Version 2 Unix, released
later in 1972. Much of PDP-11 Unix remained written in assembly until
its developers decided to rewrite the operating system in C, for Version
................................................................................
4 Unix, released in 1973. That decision allowed Unix to be relatively
easily ported to a wholly different platform — the Interdata 8/32 — in
1978 by writing a new code generator for the C compiler, then
cross-compiling everything. That success in porting Unix lead to C’s own
success first as a systems programming language, and then later as a
general-purpose programming language.

The PDP-8 was introduced by DEC in 1965 with the intention of being a
small and cheap processor that could be used in a variety of
environments. From this simple machine, the modern desktop computer
evolved, some of which were used in the writing of this document. The
PDP-8 is also arguably the ancestor of the Raspberry Pi you may be using
our CC8 compiler on, as part of the PiDP-8/I project.

The PiDP-8/I project is part of an effort to prevent the PDP-8 from
sliding into undeserved obscurity. Whether you consider it the ancestor
of the desktop computer or the embedded processor, it is a machine worth
understanding.


## CC8’s Developmental Sparks

CC8 is a C subset implementation for the DEC PDP-8 processor.

The CC8 project’s creator (Ian Schofield) thought it was time to have a





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# CC8 Manual


## A Bit of Grounding History

The PDP-8 was introduced by DEC in 1965 with the intention of being a
small and cheap processor that could be used in a variety of use cases
that were, at the time, considered low end, compared to where the rest
of the minicomputer world was at the time. It filled niches at the time
that today we’d fill with either desktop computers or embedded
processors. That makes the PDP-8 the spiritual ancestor of the iMac I’m
typing this on and of the Raspberry Pi this software is intended to run
on.

The PiDP-8/I project is part of an effort to prevent the PDP-8 from
sliding into undeserved obscurity. Whether you consider it the ancestor
of the desktop computer or the embedded processor, it is a machine worth
understanding.

The PDP-8 was roughly contemporaneous with a much more famous machine,
the PDP-11, upon which the C programming language was created. Although
a low-end PDP-11 is more powerful than even a high-end PDP-8, the fact
that their commercial lifetimes overlapped by so many years made one of
us (Ian Schofield) wonder if the PDP-8 could also support a C compiler.

The first implementation of C was on the PDP-11 as part of the early
work on the Unix operating system, and it was initially used to write
system utilities that otherwise would have been written in assembly. A C
language compiler first appeared publicly in Version 2 Unix, released
later in 1972. Much of PDP-11 Unix remained written in assembly until
its developers decided to rewrite the operating system in C, for Version
................................................................................
4 Unix, released in 1973. That decision allowed Unix to be relatively
easily ported to a wholly different platform — the Interdata 8/32 — in
1978 by writing a new code generator for the C compiler, then
cross-compiling everything. That success in porting Unix lead to C’s own
success first as a systems programming language, and then later as a
general-purpose programming language.

Although we are not likely to use CC8 to write a portable operating
system for the PDP-8, it is powerful enough to fill C’s original niche
in writing system utilities for a preexisting OS written in assembly.










## CC8’s Developmental Sparks

CC8 is a C subset implementation for the DEC PDP-8 processor.

The CC8 project’s creator (Ian Schofield) thought it was time to have a