UKC Tape Index

This file is an index to some of the more interesting things in the tape I wrote at the University of Kent at Canterbury before I left in 1990. Subsections:

• Algorithms
• Digital Signal Processing code
• C programs
• Other people's C programs
• Pascal programs
• Occam programs
• C functions and libraries
• Tutorial material on C
• Material from computing courses
• Assembly languages
  • DEC PDP-11
  • DEC VAX-11
  • Motorola 68000
  • Motorola 56000 DSP
  • High Level Hardware "Orion" Mk.0
  • Theoretical machine: the single-instruction CPU
• Software for arcane hardware
• Articles on Unix system programming
• Technical documentation
• Trivia
• Doggerel
• UKC Computing Laboratory social history 1986-1988
• Images

You can also browse the three individual directory trees, though beware: there are 34 megabytes of data here in 4500 files and directories.

• gos: my home directory from the machine used to support system administration and computer science teaching 1985-1989
• wkstn: my home directory from the workstations where I did audio research 1989-1990
• stuff: a collection of ancient Unix source codes, probably copyrighted to someone.

Algorithms

• Fast integer square root by Mr. Woo's abacus algorithm, implemented in a range of languages
• LZW compression for GIF files
• DES encryption
• How to convert Hue, Luminance, Saturation to Red, Green, Blue
• Colorvar: Variance-based colour quantisation

Digital Signal Processing code

• FFT-based sound synthesis and processing code
• Calculate sideband strengths of frequency modulation

C programs

• My first C program (!) splits a file into parts to get round local lineprinter size limits
• Wander through a labyrinth on the Sigma graphics display terminal
• Optimised anagram-finding program
• Optimised computation of fractals (with Chris Downey and David Wood)
• GENPOLY: Hidden line removal package
• DXFRIEND: Talk to a Yamaha DX7 via MIDI from an Atari ST.

Other people's C programs

• Dhrystone CPU speed benchmarking program
• A simple ray tracer (December 1986)
• Constructive Solid Geometry ray tracer (Steve A. Hill, 1990)

Pascal programs

• Tutorial example of evaluation of an expression expressed as a parse tree
• Extension of the above to read arbitrary expression from the user.

Occam programs

• Varie

C functions and libraries

• A Remote Procedure Call Mechanism for Unix (my final-year student project, Summer 1985)
• Magical algorithm to convert n° of seconds since 1 Jan 1970 to time, day, month, year etc.
• Descend a UNIX filetree, applying a function to every node.
• YACC source for generalised date parsing
• Generalised hashing routine for data storage/retrieval
• Routines to parse standard MIDI files

Tutorial material on C

• A simple program to compute and display Mandelbrot's fractal on a text terminal
• Source code for advanced tree and list operations with pointers
• An article on the difference between 2D arrays and arrays of pointers
• On "var parameters" and the names of arrays
• Reviews of a number of books on C
• The Version 6 Unix kernel (1976)

Material from computing courses

• Unix for Beginners at UKC (1987-89, with Chris Downey)
• Unix system administration (December 1988, with Chris Downey and Alan Ibbetson)
• List of topics for a lecture on the Applications of Computers to Music (March 1989)

Assembly languages

DEC PDP-11

• Machine-language assist for the V6 Unix kernel (1976-79)
• Programs and tools for the GT40 graphic display terminal

DEC VAX-11

• A (buggy) version of bcopy()
• The inner loop for the calculation of fractals
  • Mandelbrot, floating point version (Chris M. Downey, Sept 1985)
  • Mandelbrot, floating point, version 2 (Chris M. Downey, May 1986)
  • Mandelbrot, fixed point version (David C. Wood)
  • Newton-Raphson for z^3 - 1 = 0, fixed point version (David C. Wood, June-July 1986)

Motorola 68000

• Optimised inner loop for calculating of Mandelbrot's fractal
  • Using 16-bit multiply instruction
  • With extra code for 32-bit cross-multiply
• A disassembly of the Lattice C compiler's 32-bit cross-multiply
• Four different fast assembly-language routines for Conway's game of life on a monochrome bitmapped screen (Sun / Atari ST)
• A program that runs backwards

Motorola 56000 Digital Signal Processor

• A constant-time pitch shifter

High Level Hardware "Orion" Mk.0

• Various compiler-generated fragments from a project to write an object code improver

Theoretical machines

• The "Ultimate RISC machine", with just one instruction.

Software for arcane hardware

• "bbcplot" package for the UKC terminal emulator on the BBC micro
• Display code for the Regis protocol (DEC VT125, VT240 and PRO/350)
• Display code for the Gidis protocol (DEC PRO/350)
• Display code for the Sigma graphic display terminal
• A fragment of microcode for the High Level Hardware "Orion Mk0"

Articles on Unix system programming

• On the portability of C programs

Technical documentation

• Manual for the game of Hack
• "The USENET MIDI Primer"
• Extra details on MIDI
• The CMU MIDI Toolkit / Adagio + source
• On the use of fractals in music
• The memory map of the Acorn BBC microcomputer
• A description of 10 of the first commercial microcomputers
• A summary of the JANET PADs' settable parameters
• "A Report on the Internet Worm", 7 November 1987
• A list of the UK Academic sites and the computers they used in Nov 1988
• Mail messages on the subject of demand paging and control store in the HLH Orion

Trivia

• Quiz for Unix Gurus (+answers)
• Quiz for Unix Gurus #2 (+answers)
• Why HLH Orions slowly lose time
• On "Pigeon theories" in computer programming
• Program and data for the University of Utah teapot

Doggerel

• Alice's PDP-10 (pre-Jan 1988)
• Hacking on EMAS (Colin McIntyre's son, pre-Sept 1985)
• Vaxology
• Clipperwocky (MG, Feb 1988)
• Jarod and his Arch (Kevin O'Donnell, UKC, Oct 1988)
• Hakawatha (by F. X. Reid)
• F. X. Reid - The Movie (Aug 1986)
• "Disk is Full" motd (P. Collinson, Dec 1986)
• Iau Utting's "quotable quotes" file (as at May 1988)
• All I even needed to know I learned in kindergarten (Robert Fulghum)
• The winning entries in the Obfuscated C Contest 1985
• A treatise on the male orgasm
• "See them tits?" - exemplary letter of complaint

UKC Computing Lab social history

• The "unix-staff" mailing list, Oct 1986 to Aug 1987
• All the .userinfo files on the computing lab service machines, 4 Jun 1988 from:
  • eagle (general computing service),
  • merlin (first year CS undergrads),
  • falcon (second year CS undergrads),
  • gos (third year CS undergrads),
  • raven (social scientists).

Images

• Monty Python's Gumby
• A simple ray-traced world with the above as floor tile (600 Kb).
• Mike Hawleys's collection of tiny X bitmaps (Dec 1988)
  Including:
  • Peter Collinson
  • Mike Hawley
  • Brian Kernighan
  • Sam Leffler
  • Mike Lesk