Table of Contents

• Introduction
• Download
• Building
• Documentation
• Debugging Tips

Introduction

MIX is a set of tools for assembling, running and debugging programs, written in MIXAL, an assembly language for an imaginary computer, MIX, used in “The Art of Computer Programming” of D. Knuth.

This package provides a development platform for those who wish to try out examples and exercises from the book. It includes the following programs:

mixal

A MIXAL assembler, i.e. a program which translates a MIXAL source file into a program that can be run on a MIX machine.

mixsim

MIX machine simulator. There is no real, hardware, MIX machine, but you may use mixsim to emulate it and to run the programs, prepared by mixal. The mixsim utility also provides a terminal mode with a debugger, which is useful for finding and fixing bugs in your programs. It is also handy for educational purposes, as it allows to trace progam execution.

mixrun

A utility to run MIXAL programs, without creating an intermediate object file.

Download

Click here to download the recent version of the package: mix-2.0.tar.gz.
A PGP signature file is available.

The project's homepage at Puszcza contains latest news and patches for the project.

The SVN repository can be viewed online.

The repository snapshots are also available. These are created on daily basis when some changes to the repository occur. The snapshots are named mix-YYYY-MM-DD.tar.gz, where YYYY, MM and DD are decimal numbers, representing creation year, month and day, correspondinly. Read the file README-alpha to build from a snapshot.

Building

Read the files INSTALL and README, included in the distribution, for instructions on how to build the package. In the simplest (and most common) case, they boil down to the following:

 $ ./configure
 $ make
 $ make install

So far, there is only one package-specific configuration option: --without-readline. Use it if you wish to disable readline support in MIX terminal.

Documentation

Debugging tips

• The usual terminal session starts with a command

  ASGN 16 deck
  

  (where deck is the name of UNIX file containing MIX card deck).

• Set the breakpoints using BREAK command.
• Finally, type GO
• Upon encountering a breakpoint, the terminal stops and displays the instruction to be executed next. Do whatever it is necessary to do (e.g. examine the memory or registers, set new breakpoints or clear old ones, etc) and type CONT to resume execution of the program.
• You may restart the program after any breakpoint by typing GO again.
• To exit the terminal, type ^D or QUIT.