Short Contents
**************

MIX
1 Introduction to MIX
2 `mixal' - MIX Assembler.
3 `mixsim' - MIX Simulator.
4 `mixrun'
5 How to Report a Bug
Appendix A GNU Free Documentation License
Concept Index


Table of Contents
*****************

MIX
1 Introduction to MIX
2 `mixal' - MIX Assembler.
  2.1 Assembling MIXAL Programs.
  2.2 Program Listing
  2.3 Raw Object Code.
  2.4 `mixal' option summary.
3 `mixsim' - MIX Simulator.
  3.1 A MIX Machine Implementation.
  3.2 Executing MIX Programs.
  3.3 Terminal Mode and Debugger.
    3.3.1 Mixsim Commands
      3.3.1.1 Command Completion
    3.3.2 Obtaining On-line Help
    3.3.3 Quitting the Terminal
    3.3.4 Assigning and Listing Devices
    3.3.5 Running a Program
    3.3.6 Breakpoints
      3.3.6.1 Setting Breakpoints
      3.3.6.2 Deleting Breakpoints
      3.3.6.3 Disabling and Enabling Breakpoints
      3.3.6.4 Configure Breakpoints
      3.3.6.5 Listing Breakpoints
    3.3.7 Stopping and Continuing
    3.3.8 Executing Shell Commands.
    3.3.9 Examining Data and Registers
    3.3.10 A Summary of Terminal Commands.
  3.4 Command Files
  3.5 `mixsim' option summary.
4 `mixrun'
5 How to Report a Bug
Appendix A GNU Free Documentation License
Concept Index


MIX
***

This edition of the `MIX Manual', last updated 30 October 2009,
documents MIX Version 2.0.

1 Introduction to MIX
*********************

Plain 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 program execution.

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

   This manual assumes the reader has some basic notions about MIX and
MIXAL and that he has a copy of "The Art of Computer Programming"
(referred to in this book as TAOCP) at hand. The page references to
TAOCP assume the Addison-Wesley edition, 1968 (Library of congress
catalog card no. 67-26020).

2 `mixal' - MIX Assembler.
**************************

A MIX assembler is called `mixal'. The utility assembles its standard
input (or a named file), which should be a valid MIXAL program, and
writes the resulting object code to the standard output or to another
file.

   This chapter describes how to use `mixal'. The examples in this
chapter assume that the file `hello.mix' contains the following example
program:

     * ``HELLO, WORLD'' PROGRAM
     PRINTER EQU  18
             ORIG 3000
     HELLO   OUT  TEXT(PRINTER)
             JBUS *(PRINTER)
             HLT
     TEXT    ALF  HELLO
             ALF  , WOR
             ALF  LD
             END  HELLO

2.1 Assembling MIXAL Programs.
==============================

The simplest way to assemble a MIXAL program is to give it as an
argument to `mixal':

     $ mixal hello.mix

   The `mixal' utility assembles the program, and prints the resulting
object code on the standard output. The object code is formatted as a
"card deck", as described in `TAOCP, 1.3.1, p.141, ex. 26', therefore
in this book we use the terms "object file" and "deck file" as synonyms.

   Each line in the deck file corresponds to a single punch card. First
two cards are always the same -- they contain a loader routine,
responsible for loading of the entire deck into MIX memory and passing
control to the program entry point. The following lines, up to the last
one, contain the program code, formatted as described in the following
table:

Column                        Meaning
-------------------------------------------------------------------------- 
1-5                           Ignored.
6                             Number of consecutive words to be loaded
                              on this card (between 1 and 7, inclusive).
7-10                          The location of word 1 (always greater
                              than 100).
11-20                         Word 1.
21-30                         Word 2.
31-40                         Word 3.
41-50                         Word 4.
51-60                         Word 5.
61-70                         Word 6.
71-80                         Word 7.

   For example, the card:

     HELLO63000078721962107866953300000000133013558254406879733950219152384

contains 6 words to be loaded starting from address 3000. These words
are:

Address                Word
------------------------------------------------------------------- 
3000                   0787219621
3001                   0786695330
3002                   0000000133
3003                   0135582544
3004                   0687973395
3005                   0219152384

   The deck ends with a special "transfer card", which contains
information in format `TRANS0NNNN', where NNNN is the address of the
program entry point. For example, `TRANS03000' means "start execution
from address 3000".

   To illustrate this, here is the deck file produced for `hello.mix'
(the first two cards are omitted):

     HELLO63000078721962107866953300000000133013558254406879733950219152384
     TRANS03000

   The card deck, produced by `mixal' can be executed by the MIX
simulator, as described in *note mixsim::. In the simplest case, you
can directly feed the deck to the standard input of `mixsim':

     $ mixal hello.mix | mixsim

   However, for more complex programs, it is common to store the
produced card deck in a file for further use by `mixsim'.  To do so,
use `--output' (`-o') command line option, as shown in the example
below:

     $ mixal --output=hello.deck hello.mix

2.2 Program Listing
===================

To obtain more details about the generated object deck, use `--list'
(`-l') command line option. This option generates a "listing file". The
file name for this file is constructed by appending `.lst' suffix to
the base name of the input file. For example, the following invocation
will store the program listing in file `hello.lst'.

     $ mixal -l hello.mix

   If explicit input file is not given, e.g. when assembling the
standard input, the listing is named `mixal.lst'.

   These naming conventions can be overridden, by specifying the
listing name explicitly, with `--list-file' option. This option implies
`--list', so you need not give the two options together. For example,
the following invocation will store the listing in file
`out/hello.list':

     $ mixal --list-file=out/hello.list hello.mix

   The program listing contains, for each line of the input source, the
address of the corresponding MIX cell and the assembled cell contents,
as shown in the table below:

Column                        Meaning
-------------------------------------------------------------------------- 
1-4                           MIX cell address.
5                             A semicolon
7-21                          Cell contents.
23-27                         Source line number.
28 and others.                Source line.

   The cell contents (columns 7-21) is formatted as described in
`TAOCP, 1.3.1, p.124, Instruction format':

Column                        Meaning
-------------------------------------------------------------------------- 
7                             Sign.
8-12                          Address part.
14-15                         I-field.
17-18                         F-field.
20-21                         Opcode.

   The following example shows `mixal' listing for the `hello.mix'
program:

                               1 * ``HELLO, WORLD'' PROGRAM
                               2 PRINTER    EQU  18
                               3            ORIG 3000
     3000: + 3003  0 18 37     4 HELLO      OUT  TEXT(PRINTER)
     3001: + 3001  0 18 34     5            JBUS *(PRINTER)
     3002: +    0  0  2  5     6            HLT
     3003: +  517 13 13 16     7 TEXT       ALF  HELLO
     3004: + 2624 26 16 19     8            ALF  , WOR
     3005: +  836  0  0  0     9            ALF  LD
                              10            END  HELLO

   After the listing comes a "symbol table", which, for each symbol
used in the program, shows its name, location and a source line, where
it was defined. For example:

     Symbol     Value  Line
     PRINTER       18    2
     HELLO       3000    4
     TEXT        3003    7

   The `Value' column contains a MIX location, corresponding to that
symbol, except in case of macro-definitions (`EQU'), where the actual
value of the macro is printed (see `PRINTER' in the example above).

   The symbol table contains not only user-defined symbols, but also
any literals and local labels used in the program. For literals, the
`Symbol' column contains their computed w-expressions, surrounded by
equals sings. For example, the line

             MUL  =2*25+1=

will produce the symbol name `=51=', e.g.:

     Symbol     Value  Line
     =51=        1101   18

   Local labels are displayed as two integer numbers, separated by a
dash and surrounded by vertical bars (`|'). The first number
corresponds to the number of the local label, the second one means its
ordinal number in the program text. For example, the MIXAL fragment
below:

     1H      INCX 0
             DECA 11
             JANP 1B
     1H      INCX 1

will produce the following two entries in the symbol table:

     Symbol     Value  Line
     |1-1|       1026    7
     |1-2|       1029   10

   An additional statistics about the input source can be obtained
using `--xref' (`-x') option, which instructs `mixal' to print a
cross-reference table of all used symbols.  A "cross-reference table"
is added as an additional column to the symbol table, described above.
The contents of this column lists the lines where the symbol was
referenced. The following example shows a cross-reference table for the
`hello.mix' program:

     Symbol     Value  Line  Referenced on line
     PRINTER       18    2    4    5
     HELLO       3000    4   10
     TEXT        3003    7    4

   If `--xref' is used without `--list' (or `--list-file'), the symbol
table is printed on the standard error.

2.3 Raw Object Code.
====================

Sometimes you may need to assemble a MIXAL program into a raw sequence
of bytes, without composing a proper load deck. In particular, this
becomes necessary if you wish to develop your own loading routine. The
`--raw-output' (`-r') allows you to do that. When called with this
option, `mixal' outputs assembled code as is, without converting it to
object card format and without prefixing it with loader routine.
Currently this option assumes that the produced code will be read using
device 16 (card reader), so the output byte stream is formatted in
blocks of 16 words (80 bytes) delimited by newlines.

   A particularly interesting implementation of this feature would be
to produce a loader code for another type of input device, e.g. to load
programs from magnetic tapes or disks. This, however, requires some
further work on `mixsim' and will be implemented in future versions of
the package.

2.4 `mixal' option summary.
===========================

     Usage:
     mixal [OPTIONS] [FILE]

The following table summarizes the available command line options:

`--list'
`-l'
     Produce a source listing. Unless `--list-file' (see below) is
     used, the default listing file name is constructed by appending
     `.lst' suffix to the base name of the input file. If standard
     input is used, the listing file is named `mixal.lst'.

     *Note listing::.

`--list-file=FILE'
     Set listing file name. Implies `--list'.

     *Note mixal-list-file::.

`--force'
`-f'
     Force generating object deck (and, eventually, listing) even if
     there were errors during assembly.

`--output=FILE'
`-o'
     Set output file name. By default, object deck is printed on the
     standard output.

     *Note mixal-output::.

`--raw-output'
`-r'
     Produce raw object output.

     *Note raw output::.

`--xref'
`--cross-reference'
`-x'
     Output a cross reference.

     *Note mixal-xref::.

`--debug-gram'
     Enable parser debugging output.

`--debug-lex'
     Enable lexical analyzer debugging output.

`-d LEVEL'
     Set debug level. This option is for compatibility with previous
     versions. The `-dy' option is equivalent to `--debug-gram', `-dl'
     is equivalent to `--debug-lex', `-dyl' (or `-dly') is equivalent
     to both.

`--help'
`-h'
     Print a concise help summary.

`--version'
`-V'
     Print program version and license information.

3 `mixsim' - MIX Simulator.
***************************

The MIX simulator, `mixsim', allows you to execute object code
assembled by `mixal', and to inspect the machine state at any stage of
the execution. The simulator also includes a debugging facility, useful
when analyzing the examples and solving problems from TAOCP.

   The simulator is written in compliance with the recommendations found
in `TAOCP, 1.4.3.1, p.198, MIX Simulator'.

3.1 A MIX Machine Implementation.
=================================

The simulator implements the MIX machine as described in `TAOCP, 1.3.1,
p.120, Description of MIX'. The machine is shipped with all external
equipment, except the paper tape unit(1), and the floating point
feature.

   Each I/O device is bound to a particular UNIX file.  By default the
card reader is connected to stdin, the printer to stdout and the card
punch to stderr. The typewriter is connected to stdin. The paper tape
unit is not yet implemented.

   The tape units use files `tape0' to `tape7' and the disk units use
files `disk0' to `disk8' in the current directory.  None of these files
is required to exist: they will be created on demand, when the first
output operation on the given unit takes place.

   The disks are always opened for update without truncation, so that
old data is not destroyed until it is overwritten. Note that big disk
files will never shrink unless they are deleted.

   In contrast, the tapes are always opened with truncation, so that
any existing data is lost after the first `OUT' instruction is executed.

   ---------- Footnotes ----------

   (1) It will be implemented in future releases

3.2 Executing MIX Programs.
===========================

When run without command line options, `mixsim' reads a load deck from
device 16, loads and executes it, writing any error messages to stderr.
On completion, a dump of the machine state is written to stderr. If
`mixsim' is interrupted during execution, the machine state will be
dumped to stderr.

   At most one argument can be given. It is treated as a file name to
be assigned to the card reader device. Thus, there are three ways to
execute a load deck previously stored in a file:

  a. Redirect the file's contents to the `mixsim' stdin:

          $ mixsim < hello.deck

  b. Give the file name as an argument to `mixsim':

          $ mixsim hello.deck

  c. Assign the file to device `#16', using `-a' option (see below):

          $ mixsim -a 16=hello.deck

   The default device assignments can be changed using
`--assign-device' (`-a') command line option. It takes a single
argument in the form DEV=FILE, where DEV is the MIX device number and
FILE is the name of file to be assigned to it. For example, the
following invocation tells `mixsim' to connect the card puncher (device
17) to file `punch.out':

     $ mixsim --assign 17=punch.out

3.3 Terminal Mode and Debugger.
===============================

When given the `--terminal' (`-t') option, `mixsim' starts in "terminal
mode". The terminal mode provides a custom shell for executing, tracing
and debugging MIX programs. When you start `mixsim' in this mode, you
will see:

     $ mixsim -t

     MIX TERMINAL STATION READY FOR COMMUNICATION

     MIX> _

   The `MIX>' string at the end of the screen is the "terminal prompt",
inviting you to enter a command. The syntax of terminal commands is
similar to that of shell: each command consists of a "command verb",
optionally followed by one or more "arguments", separated by any amount
of whitespace. A command ends with a newline character.

3.3.1 Mixsim Commands
---------------------

All `mixsim' command verbs (hereinafter referred to as "commands") are
case-insensitive. Each command has a full and contracted form, the
latter one being designed to save extra typing.

   If the package is configured with `readline' support enabled (which
is the default, if `readline' is present on the system), you can
abbreviate a command to the first few letters of the command name, if
that abbreviation is unambiguous. A flexible command line editing
facility is also available in this case. *Note completion::, for a
detailed description.

   You can test if an abbreviation is valid by using it as an argument
to the `help' command (*note help::).

   A blank line as input to GDB (typing just `RET') means to repeat the
previous command.

   Any text from a `#' to the end of the line is a comment; it is
ignored.  This is useful mainly in command files (*note command
files::).

3.3.1.1 Command Completion
..........................

This subsection discusses the command completion facility, available if
`mix' is configured with `readline' support. Using this feature is
recommended. If you don't have GNU `readline', we suggest you to get it
from the Readline Home Page
(http://cnswww.cns.cwru.edu/php/chet/readline/rltop.html) prior to
compiling `mix'.

   *Note Command Line Editing: (readline)Command Line Editing, for more
information about the library.

   `Mixsim' can fill in the rest of a word in a command for you, if
there is only one possibility; it can also show you what the valid
possibilities are for the next word in a command, at any time.

   Press the `TAB' key whenever you want `mixsim' to fill out the rest
of a word for you. If there is only one possibility, it will replace
the partial word and will wait for you to finish the command. This
"command completion" is context-dependent. For example, if you type:

     MIX> br_TAB

this command will immediately be expanded to `break', since it is the
only possibility in this context:

     MIX> break

   If there is more than one possibility to complete the word you are
typing, `mixsim' rings a bell. You can either supply more characters
and try again, or just press `TAB' one more time, in which case
`mixsim' will display all the possible completions for that word. For
example, the `address' command (*note breakpoints::) can be followed by
several keywords, so, if you type `TAB' after `address', `mixsim' rings
a bell and waits for your further actions. If you press `TAB' second
time, you'll see:

     MIX> ADDRESS _TAB
     A bell sounds. Pess `TAB' again to see:
     CB         DELETE     ENABLE     INFO       LIST
     CLEAR      DISABLE    IGNORE     LB         PASSCOUNT
     MIX> ADDRESS _

   To save you typing, it is also possible to view the list of
alternatives in the first place. To do so, type `M-?', instead of
pressing `TAB' twice. `M-?' means either to hold down a key designated
as the `META' shift on your keyboard (if there is one) while typing
`?', or to press `ESC', followed by `?'.

   If the context requires you to type a file name, `mixsim' will
complete file names. For example:

     MIX> ASGN 16 ../examples/_M-?
     mystery.mix    hello.mix      init.mix       p.mix
     easter.mix     load.mix       tsort.mix

   Similarly, if the context requires a name of an executable file, you
will see the appropriate completion, made using your `PATH' environment
variable setting:

     MIX> ! ca_TAB TAB
     cat             cal

3.3.2 Obtaining On-line Help
----------------------------

`HELP'
`?'
     To obtain help about all available commands, type `HELP'.

`HELP CMD'
`? CMD'
     When used with an argument, it displays usage summary for the
     given command verb, e.g.:

          MIX> HELP ASGN
          ASGN <DEVICE> <FILE>

3.3.3 Quitting the Terminal
---------------------------

`QUIT'
`Q'
     To exit the terminal, use the `QUIT' (abbreviated `Q'), or type an
     end-of-file character (usually `C-d').

   An interrupt (`C-c') does not exit from `mixsim', but rather stops
the program being executed (*note stopping::), or, if no program is
being run, cancels the current input line.

3.3.4 Assigning and Listing Devices
-----------------------------------

`ASGN DEVICE FILE'
`A DEVICE FILE'
     Assign FILE to the given MIX device. DEVICE specifies the device
     number. In the effect of this command, output operations on DEVICE
     will write the data to FILE, and input operations on DEVICE will
     read data from FILE.

   For example, to assign file `hello.deck' to the card reader, type:

     MIX> ASGN 16 hello.deck

   To obtain information about MIX devices, including their current
assignments, use the following command:

`INFO IO [DEVICE]'
`LIST IO [DEVICE]'
`LI [DEVICE]'
     Without arguments, lists all devices. With a numeric argument,
     shows information about that particular device. For more uses of
     `INFO' command, see *note list breakpoints::.

   The information is displayed in tabular form and contains the
following columns:

UNIT
     Unit number.

IOT
     I/O time per block.

SKT
     Seek time.

ADDR
     Memory address for the pending I/O operation.

POS
     Device position for the pending I/O operation. This column is
     meaningful only for tape and disk devices.

OP
     Opcode or `N/A', if no operation is pending.

CLOCK
     Clock time when the I/O will occur. To examine the current clock
     time, see *note list breakpoints::.

ASGN
     File assigned to that device.

   The example below shows the information about card reader, obtained
after the first loader card was read:

     MIX> info io 16
     UNIT    IOT    SKT  ADDR  POS   OP  CLOCK ASGN
       16  10000      0    16    0   IN  15000 easter.obj

3.3.5 Running a Program
-----------------------

`GO'
`G'
`RUN'
`R'
     Emulates MIX GO button.

   This command does the following:

  a. A single card is read into locations `0000--0015';

  b. When the card has been completely read and the card reader is no
     longer busy, a `JMP' to location `0000' occurs. The J-register is
     also set to 0.

3.3.6 Breakpoints
-----------------

A "breakpoint" makes your program stop whenever a certain location in
the program is reached. When the program stops at a breakpoint we say
that this breakpoint has been "passed" or "hit".

   For each breakpoint, two numbers are defined: "ignore count", which
specifies the number of passes before that breakpoint is enabled, and
"pass count", which specifies the number of passes after which the
breakpoint will be deleted.

   Each created breakpoint is assigned a "sequence number", which can
be used to refer to that breakpoint in other commands. Another way to
refer to a breakpoint is by the program location it is set at. Thus,
each command described in this subsection has two forms: a form which
uses breakpoint numbers, and a form that uses program locations. The
second form is constructed by prefixing the command with `ADDRESS'
keyword (abbreviated `AD'). For example, the following command deletes
breakpoint number 2 (*note delete breakpoints::):

     MIX> DELETE 2

In contrast, the following command deletes all breakpoints set at
address 1000:

     MIX> ADDRESS DELETE 1000

3.3.6.1 Setting Breakpoints
...........................

Breakpoints are set with the `BREAK' command (abbreviated `B').

`BREAK LOCATION'
`B LOCATION'
     Set a breakpoint at the given LOCATION. Both ignore and pass
     counts are set to 0. A sequence number assigned to the breakpoint
     is displayed, as shown in the example below:

          MIX> BR 1000
          BREAKPOINT 1 IS SET AT ADDRESS 1000

     This sequence number can then be used to refer to this breakpoint.

`BREAK TEMP LOCATION'
`BT LOCATION'
`TB LOCATION'
     Sets a temporary breakpoint at the given LOCATION. A "temporary
     breakpoint" is a breakpoint which is deleted after a single hit.
     In other words, it has pass count set to 1.

     This command is equivalent to:

          BREAK LOCATION
          ADDRESS PASSCOUNT LOCATION 1

     *Note configure breakpoints::, for information about `PASSCOUNT'
     command.

   You can set any number of breakpoints at the same place in your
program. This feature is not very useful at the moment, it is reserved
for future use.

3.3.6.2 Deleting Breakpoints
............................

It is often necessary to eliminate a breakpoint which has done its job
and is no longer needed. This is called "deleting" the breakpoint. A
deleted breakpoint no longer exists, and its sequence number is
returned to the pool of available numbers.

   It is not necessary to delete a breakpoint to proceed past it.
`Mixsim' automatically ignores breakpoints on the first instruction to
be executed when you continue execution without changing the execution
address.

`DELETE [NUMBER-LIST]'
`D [NUMBER-LIST]'
     Delete specified breakpoints. NUMBER-LIST is a
     whitespace-separated list of breakpoint numbers. If no argument is
     specified, delete all breakpoints (in this case `mixsim' asks
     confirmation).

     When prefixed with `ADDRESS' (abbreviated `AD'), NUMBER-LIST is
     treated as a list of addresses, instead of breakpoint numbers.

   Examples:

  1. Delete all breakpoints:
          MIX> DELETE

  2. Delete breakpoints 1, 3 and 5:
          MIX> DELETE 1 3 5

  3. Delete breakpoints set at addresses 1000 and 3000:
          MIX> ADDRESS DELETE 1000 3000

3.3.6.3 Disabling and Enabling Breakpoints
..........................................

Instead of deleting a breakpoint, you might prefer to "disable" it. A
disabled breakpoint continues to exist, but is ignored. You may enable
it again later, if the need arises.

   To disable and enable breakpoints, use `ENABLE' and `DISABLE'
commands, described below. To obtain information about existing
breakpoints and their status, use `INFO BREAK' command (*note list
breakpoints::).

`DISABLE [NUMBER-LIST]'
`DIS [NUMBER-LIST]'
     Disable breakpoints, specified by NUMBER-LIST. If no arguments are
     given, disables all breakpoints.

`ENABLE NUMBER-LIST'
`ENA NUMBER-LIST'
     Enable breakpoints, specified by NUMBER-LIST. If no arguments are
     given, enables all breakpoints.

   Both commands may be prefixed with `ADDRESS' (abbreviated `AD'), to
specify breakpoints by MIX addresses, rather than by breakpoint numbers.

3.3.6.4 Configure Breakpoints
.............................

Each breakpoint has two numbers associated with it: "ignore count",
which specifies the number of passes before that breakpoint is enabled,
and "pass count", which specifies the number of passes after which the
breakpoint will be deleted.

`IGNORE NUMBER COUNT'
`I NUMBER COUNT'
     Set ignore count for breakpoint NUMBER to COUNT.

`PASSCOUNT NUMBER COUNT'
`P NUMBER COUNT'
     Set pass count for breakpoint NUMBER to COUNT.

   Both commands may be prefixed with `ADDRESS' (abbreviated `AD'), in
which case their first argument, N, is treated as a MIX location where
the breakpoint is set, rather than its number. For example, the
following command sets pass count to 1 for all breakpoints set at
location 1000:

     MIX> ADDRESS PASSCOUNT 1000 1

3.3.6.5 Listing Breakpoints
...........................

`INFO BREAK [NUM]'
`LIST BREAK [NUM]'
`LB [NUM]'
     Without argument, lists all existing breakpoints. With an argument,
     lists only breakpoint NUM. When prefixed with `ADDRESS'
     (abbreviated `AD'), treats its argument as a MIX location and
     lists breakpoints set at that location.

   Following is an example of a breakpoint listing:

      NUM  LOC  ENB  CNT  IGN  PAS
        1 1000    Y    1    0    0
        2 1040    N   10    8    0
        3 1230    Y    0    0    1

   The columns and their meanings are:

Column                 Meaning
------------------------------------------------------------------- 
NUM                    Breakpoint number.
LOC                    Location.
ENB                    Is the breakpoint enabled or not.
CNT                    Number of passes registered this far.
IGN                    Ignore count.
PAS                    Pass count.

3.3.7 Stopping and Continuing
-----------------------------

The principal purposes of using a debugger are so that you can stop
your program before it terminates; or so that, if your program runs
into trouble, you can investigate and find out why.

   Inside `mixsim' a program may stop either because it hit an active
breakpoint or because it reached a new line after `NEXT' or `STEP'
command (see below). Additionally, you can stop a running program at
any moment, by pressing interrupt (usually `C-c').

`CONTINUE'
`C'
     Continue program execution, at the address where it last stopped.

   A typical debugging technique is to set a breakpoint (*note set
breakpoints::) at the location where a problem is believed to lie, run
your program until it stops at that breakpoint, and then step through
the suspect area, examining the variables that are interesting, until
you see the problem happen.

   The following two commands are useful with this technique.

`NEXT [COUNT]'
`N [COUNT]'
     Execute next instruction and stop again. With an argument, execute
     next COUNT instructions. If any of the executed instructions is a
     function call, that function is not descended into.

`STEP [COUNT]'
`S [COUNT]'
     Execute next instruction and stop again. If the instruction is a
     function call, descend into that function. With an argument,
     execute next COUNT instructions.

3.3.8 Executing Shell Commands.
-------------------------------

`SHELL [COMMAND]'
`! [COMMAND]'
     Execute given shell command, by running `/bin/sh -c COMMAND'.  For
     example, to see the listing of the current working directory, do:

          MIX> ! ls -l

     If no arguments are supplied, execute a subordinate shell.

3.3.9 Examining Data and Registers
----------------------------------

`DUMP'
`DU'
     Dump MIX registers and memory contents. The output format is
     described below.

`DUMP MEMORY [FROM [TO]]'
`DM [FROM [TO]]'
     Dump MIX memory. When used without arguments, dumps entire address
     space. When used with one argument, dumps the memory contents
     starting from location FROM. When used with two arguments, dumps
     the contents of memory between the locations FROM and TO,
     inclusive. Both locations are rounded to the nearest word boundary.

     The output is formatted in blocks, each one containing 5 machine
     words. Each block is preceded by the location of its first word.
     Each word is printed in three forms, located in rows. The first
     row is the decimal value of the word, the second row is its
     representation in instruction format (`TAOCP, 1.3.1, p.124,
     Instruction format'), and the last one gives its printable
     representation. For example, the words `3000--3004' of `hello.mix'
     code look as follows:

          3000 +0000787219621 +0000786695330 +0000000000133
               +3003 00 18 37 +3001 00 18 34 +0000 00 02 05
               '*d Q7'        '*b Q4'        '   BE'

               +0000135582544 +0000687973395
               +0517 13 13 16 +2624 26 16 19
               'HELLO'        ', WOR'

     The above example is split in two groups due to printing
     restrictions.

     If several blocks of memory contain the same data, only first of
     them is displayed, the rest being replaced by a message, similar
     to the following:

              Lines 3015 to 3995 are the same.

`DUMP REGISTERS'
`DR'
     Dump contents of MIX registers. The following example illustrates
     the output format:

     Registers A/X    +00000000000 +00041363636
                      +          0 +    8775582

     Index Registers  +00000  +00000  +05670  +00000  +00000  +00000
                      +    0  +    0  + 3000  +    0  +    0  +    0

     Jump Register    +00015     Overflow toggle:      OFF
                      +   13     Comparison Indicator: EQUAL

     Clock = 262436 u. Location = 3001, M 3003, I 0, F 18, C 37,
     inst = + 5673002245

`DISASSEMBLE [FROM [TO]]'
`UNASM [FROM [TO]]'
`U [FROM [TO]]'
     Dump a range of memory FROM-TO as MIX instructions. If TO is not
     given, disassemble first five words starting at FROM. If no
     arguments are given, disassemble first five words starting from
     the current instruction pointer:

          MIX> disassemble 0
          0       IN    16(16)
          1       IN    29(16)
          2       LD1   0(0:0)
          3       JBUS  *(16)
          4       LDA   30


3.3.10 A Summary of Terminal Commands.
--------------------------------------

For convenience, this section lists all available terminal commands in
alphabetical order, along with a short description and a reference to
their detailed description.

 -- Terminal Command: ADDRESS BREAKPOINT-COMMAND
     BREAKPOINT-COMMAND is any of the following commands with
     appropriate arguments: `DELETE', `ENABLE', `INFO BREAK',
     `DISABLE', `IGNORE', `PASSCOUNT'.

     The `ADDRESS' prefix makes BREAKPOINT-COMMAND to refer to
     breakpoints using memory locations they are set as, rather than
     breakpoint numbers. *Note ADDRESS prefix: breakpoints.

 -- Terminal Command: ASGN DEVICE FILE
     Assign FILE to the given MIX device.

     *Note devices::.

 -- Terminal Command: BREAK [TEMP] LOCATION
     Set a breakpoint at the given LOCATION. If `TEMP' is given, set a
     temporary breakpoint, active for one pass only.

     *Note breakpoints::.

 -- Terminal Command: BT LOCATION-LIST
 -- Terminal Command: TB LOCATION-LIST
     Shortcut for `BREAK TEMP'.

 -- Terminal Command: DELETE [NUM-LIST]
     Delete specified breakpoints. NUM-LIST is a list of breakpoint
     numbers or, if `ADDRESS' prefix is used, their addresses.  Without
     arguments, delete all breakpoints.

     *Note delete breakpoints::.

 -- Terminal Command: CONTINUE
 -- Terminal Command: C
     Continue program execution, at the address where it last stopped.

     *Note stopping::.

 -- Terminal Command: DISABLE [NUM-LIST]
     Disable breakpoints. NUM-LIST is a list of breakpoint numbers or,
     if `ADDRESS' prefix is used, their addresses.  Without arguments,
     disable all breakpoints.

     *Note disable breakpoints::.

 -- Terminal Command: DISASSEMBLE [FROM [TO]]
 -- Terminal Command: UNASM [FROM [TO]]
 -- Terminal Command: U [FROM [TO]]
     Dump a range of memory as MIX instructions.

     *Note DISASSEMBLE: data.

 -- Terminal Command: DUMP
 -- Terminal Command: DU
     Dump MIX registers and memory contents.

     *Note data::.

 -- Terminal Command: DUMP REGISTERS
 -- Terminal Command: DR
     Dump contents of MIX registers.

     *Note DUMP REGISTERS: data.

 -- Terminal Command: DUMP MEMORY [FROM [TO]]
 -- Terminal Command: DM [FROM [TO]]
     Dump MIX memory.

     *Note DUMP MEMORY: data.

 -- Terminal Command: ENABLE [NUM-LIST]
     Enable breakpoints. NUM-LIST is a list of breakpoint numbers or,
     if `ADDRESS' prefix is used, their addresses.  Without arguments,
     enable all breakpoints.

     *Note ENABLE: disable breakpoints.

 -- Terminal Command: GO
 -- Terminal Command: RUN
     Run a program. *Note running::.

 -- Terminal Command: HELP [COMMAND-VERB]
 -- Terminal Command: ? [COMMAND-VERB]
     Display a short usage summary about COMMAND-VERB. Without
     arguments, display all available commands.

     *Note help::.

 -- Terminal Command: IGNORE NUMBER COUNT
     Set ignore count for breakpoint NUMBER to COUNT.  NUMBER is a
     breakpoint number or, if `ADDRESS' prefix is used, its address.

     *Note IGNORE: configure breakpoints.

 -- Terminal Command: INFO BREAK [NUM]
 -- Terminal Command: LIST BREAK [NUM]
 -- Terminal Command: LB [NUM]
     Without argument, lists all existing breakpoints. With an argument,
     lists only breakpoint NUM. May be prefixed with `ADDRESS' to use
     breakpoint address instead of number.

     *Note list breakpoints::.

 -- Terminal Command: INFO IO [NUM]
 -- Terminal Command: LIST IO [NUM]
 -- Terminal Command: LI [NUM]
     Without arguments, list all devices. With a numeric argument, show
     information about that particular device.

     *Note INFO IO: devices.

 -- Terminal Command: NEXT [COUNT]
     Execute next COUNT (default is 1) instructions and stop again.

     *Note NEXT: stopping.

 -- Terminal Command: PASSCOUNT NUMBER COUNT
     Set pass count for breakpoint NUMBER to COUNT.

     NUMBER is a breakpoint number or, if `ADDRESS' prefix is used, its
     address.

     *Note PASSCOUNT: configure breakpoints.

 -- Terminal Command: SOURCE FILENAME
 -- Terminal Command: SO FILENAME
     Execute the command file FILENAME.

     *Note command files::, for more information about command files and
     their execution.

 -- Terminal Command: QUIT
     Quit the terminal. *Note quitting::.

 -- Terminal Command: SHELL [COMMAND]
 -- Terminal Command: ? [COMMAND]
     Execute given shell command. *Note shell commands::.

 -- Terminal Command: STEP [COUNT]
     Execute next COUNT (default is 1) instructions and stop again. If
     a function call is encountered, descend into the function.

     *Note STEP: stopping.

3.4 Command Files
=================

A "command file" is a file containing `mixsim' commands, one per line.
Comments (lines starting with `#') and empty lines are also allowed. An
empty line in a command file does nothing; it does not mean to repeat
the last command, as it would from the terminal.

   Command files are useful to store sequences of `mixsim' commands for
executing them later. There are two ways to execute a command file:
explicit, by using `SOURCE' command, or implicit, by naming the file
`.mixsim' and storing it in the current working directory.

`SOURCE FILENAME'
`SO FILENAME'
     Execute the command file FILENAME.

   The lines in a command file are executed sequentially.  They are not
printed as they are executed.  An error in any command terminates
execution of the command file and control is returned to the console.
However, any `mixsim' command that prints a diagnostic message saying
what it is doing, continues to do so even when called from a command
file.

   Commands that would ask for confirmation if used interactively
proceed without asking, as if an affirmative answer was obtained.

   When started in terminal mode (*note terminal::), `mixsim' searches
for file named `.mixsim' in the current working directory, and, if this
file exists, executes it. This file can be used to provide necessary
default settings. For example, the following `.mixsim' file assigns
`easter.dck' to the card reader device and sets breakpoint at address
`1000':

     asgn 16 easter.dck
     br 1000

3.5 `mixsim' option summary.
============================

This section summarizes `mixsim' command line options.

     Usage:
     mixsim [OPTIONS] [DECK-FILE]

`--assign-device=DEV=FILE'
`-a DEV=FILE'
     Assign FILE to the MIX device DEV.

     *Note exec::.

`--terminal'
`-t'
     Run in terminal mode.

     *Note terminal::.

`--help'
`-h'
     Print a concise help summary.

`--version'
`-V'
     Print program version and license information.

4 `mixrun'
**********

The MIX package provides a utility for assembling and executing a MIXAL
file in one run. The utility is called `mixrun'. In its simplest form,
it is called with the name of MIXAL source file as an argument, e.g.:

     $ mixrun hello.mix
     HELLO, WORLD

     Registers A/X    +00000000000 +00041363636
                      +          0 +    8775582

     Index Registers  +00000  +00000  +05670  +00000  +00000  +00000
                      +    0  +    0  + 3000  +    0  +    0  +    0
     ...

   By default, a dump of the machine state is produced at the standard
error. To direct it to another file, use `--dump' (`-d') command line
option, e.g.: `mixrun --dump=hello.dump hello.mix'.

   To suppress the dump, use `--no-dump' command line option.

   You can also request producing a listing file. To do so, use
`--list' (`-l') option. By default, the name of the listing file is
constructed by appending `.lst' suffix to the base name of the input
file. To use another file, give its name as an argument to `--list', as
in the example below:

     $ mixrun --list=my.list `input'
     # or:
     $ mixrun -lmy.list `input'

   Notice, that an argument to `--list' option must be separated from
it by an equals sign, with no whitespace on any side of it. Similarly,
when a short form, `-l', is used, its argument must follow the option
immediately.

   As any other MIX program, `mixrun' understands two informational
options. The option `--version' (`-V') displays the program version and
a short licensing information, and the option `--help' (`-h') shows a
short usage summary.

5 How to Report a Bug
*********************

Email bug reports to <gray@gnu.org.ua>.

   As the purpose of bug reporting is to improve software, please be
sure to include maximum information when reporting a bug. The
information needed is:

   * Version of the package you are using.

   * Compilation options used when configuring the package.

   * Conditions under which the bug appears.

Appendix A GNU Free Documentation License
*****************************************

                     Version 1.3, 3 November 2008

     Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
     `http://fsf.org/'

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

  0. PREAMBLE

     The purpose of this License is to make a manual, textbook, or other
     functional and useful document "free" in the sense of freedom: to
     assure everyone the effective freedom to copy and redistribute it,
     with or without modifying it, either commercially or
     noncommercially.  Secondarily, this License preserves for the
     author and publisher a way to get credit for their work, while not
     being considered responsible for modifications made by others.

     This License is a kind of "copyleft", which means that derivative
     works of the document must themselves be free in the same sense.
     It complements the GNU General Public License, which is a copyleft
     license designed for free software.

     We have designed this License in order to use it for manuals for
     free software, because free software needs free documentation: a
     free program should come with manuals providing the same freedoms
     that the software does.  But this License is not limited to
     software manuals; it can be used for any textual work, regardless
     of subject matter or whether it is published as a printed book.
     We recommend this License principally for works whose purpose is
     instruction or reference.

  1. APPLICABILITY AND DEFINITIONS

     This License applies to any manual or other work, in any medium,
     that contains a notice placed by the copyright holder saying it
     can be distributed under the terms of this License.  Such a notice
     grants a world-wide, royalty-free license, unlimited in duration,
     to use that work under the conditions stated herein.  The
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     accept the license if you copy, modify or distribute the work in a
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     A "Modified Version" of the Document means any work containing the
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     A "Secondary Section" is a named appendix or a front-matter section
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     The "Invariant Sections" are certain Secondary Sections whose
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     The Document may include Warranty Disclaimers next to the notice
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  2. VERBATIM COPYING

     You may copy and distribute the Document in any medium, either
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     You may also lend copies, under the same conditions stated above,
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  3. COPYING IN QUANTITY

     If you publish printed copies (or copies in media that commonly
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     If the required texts for either cover are too voluminous to fit
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     If you publish or distribute Opaque copies of the Document
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     It is requested, but not required, that you contact the authors of
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     version of the Document.

  4. MODIFICATIONS

     You may copy and distribute a Modified Version of the Document
     under the conditions of sections 2 and 3 above, provided that you
     release the Modified Version under precisely this License, with
     the Modified Version filling the role of the Document, thus
     licensing distribution and modification of the Modified Version to
     whoever possesses a copy of it.  In addition, you must do these
     things in the Modified Version:

       A. Use in the Title Page (and on the covers, if any) a title
          distinct from that of the Document, and from those of
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       B. List on the Title Page, as authors, one or more persons or
          entities responsible for authorship of the modifications in
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       C. State on the Title page the name of the publisher of the
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       D. Preserve all the copyright notices of the Document.

       E. Add an appropriate copyright notice for your modifications
          adjacent to the other copyright notices.

       F. Include, immediately after the copyright notices, a license
          notice giving the public permission to use the Modified
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       G. Preserve in that license notice the full lists of Invariant
          Sections and required Cover Texts given in the Document's
          license notice.

       H. Include an unaltered copy of this License.

       I. Preserve the section Entitled "History", Preserve its Title,
          and add to it an item stating at least the title, year, new
          authors, and publisher of the Modified Version as given on
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          then add an item describing the Modified Version as stated in
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       J. Preserve the network location, if any, given in the Document
          for public access to a Transparent copy of the Document, and
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       K. For any section Entitled "Acknowledgements" or "Dedications",
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       L. Preserve all the Invariant Sections of the Document,
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       M. Delete any section Entitled "Endorsements".  Such a section
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       N. Do not retitle any existing section to be Entitled
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       O. Preserve any Warranty Disclaimers.

     If the Modified Version includes new front-matter sections or
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     publisher that added the old one.

     The author(s) and publisher(s) of the Document do not by this
     License give permission to use their names for publicity for or to
     assert or imply endorsement of any Modified Version.

  5. COMBINING DOCUMENTS

     You may combine the Document with other documents released under
     this License, under the terms defined in section 4 above for
     modified versions, provided that you include in the combination
     all of the Invariant Sections of all of the original documents,
     unmodified, and list them all as Invariant Sections of your
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     their Warranty Disclaimers.

     The combined work need only contain one copy of this License, and
     multiple identical Invariant Sections may be replaced with a single
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     combined work.

     In the combination, you must combine any sections Entitled
     "History" in the various original documents, forming one section
     Entitled "History"; likewise combine any sections Entitled
     "Acknowledgements", and any sections Entitled "Dedications".  You
     must delete all sections Entitled "Endorsements."

  6. COLLECTIONS OF DOCUMENTS

     You may make a collection consisting of the Document and other
     documents released under this License, and replace the individual
     copies of this License in the various documents with a single copy
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     You may extract a single document from such a collection, and
     distribute it individually under this License, provided you insert
     a copy of this License into the extracted document, and follow
     this License in all other respects regarding verbatim copying of
     that document.

  7. AGGREGATION WITH INDEPENDENT WORKS

     A compilation of the Document or its derivatives with other
     separate and independent documents or works, in or on a volume of
     a storage or distribution medium, is called an "aggregate" if the
     copyright resulting from the compilation is not used to limit the
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     If the Cover Text requirement of section 3 is applicable to these
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  8. TRANSLATION

     Translation is considered a kind of modification, so you may
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     4.  Replacing Invariant Sections with translations requires special
     permission from their copyright holders, but you may include
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     If a section in the Document is Entitled "Acknowledgements",
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     Preserve its Title (section 1) will typically require changing the
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  9. TERMINATION

     You may not copy, modify, sublicense, or distribute the Document
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     otherwise to copy, modify, sublicense, or distribute it is void,
     and will automatically terminate your rights under this License.

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 10. FUTURE REVISIONS OF THIS LICENSE

     The Free Software Foundation may publish new, revised versions of
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 11. RELICENSING

     "Massive Multiauthor Collaboration Site" (or "MMC Site") means any
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     The operator of an MMC Site may republish an MMC contained in the
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ADDENDUM: How to use this License for your documents
====================================================

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:

       Copyright (C)  YEAR  YOUR NAME.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3
       or any later version published by the Free Software Foundation;
       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
       Texts.  A copy of the license is included in the section entitled ``GNU
       Free Documentation License''.

   If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts." line with this:

         with the Invariant Sections being LIST THEIR TITLES, with
         the Front-Cover Texts being LIST, and with the Back-Cover Texts
         being LIST.

   If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

   If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.

Concept Index
*************

This is a general index of all issues discussed in this manual.

!:                                             See 3.3.8.    (line  892)
"Hello, world" program.:                       See 2.        (line   99)
.mixsim:                                       See 3.4.      (line 1153)
?:                                             See 3.3.10.   (line 1065)
a, -a short option, description:               See 3.2.      (line  457)
ADDRESS <1>:                                   See 3.3.10.   (line  984)
ADDRESS:                                       See 3.3.6.    (line  690)
addressing breakpoints:                        See 3.3.6.    (line  690)
ASGN <1>:                                      See 3.3.10.   (line  993)
ASGN:                                          See 3.3.4.    (line  604)
assembling:                                    See 2.1.      (line  117)
assign, --assign option, summary:              See 3.5.      (line 1171)
assign-device, --assign-device option, description:See 3.2.  (line  457)
assigning files to devices:                    See 3.2.      (line  457)
B:                                             See 3.3.6.1.  (line  711)
BREAK <1>:                                     See 3.3.10.   (line  998)
BREAK:                                         See 3.3.6.1.  (line  711)
BREAK TEMP:                                    See 3.3.6.1.  (line  722)
breakpoint:                                    See 3.3.6.    (line  681)
breakpoint number:                             See 3.3.6.    (line  690)
breakpoints, referring to:                     See 3.3.6.    (line  690)
BT <1>:                                        See 3.3.10.   (line 1004)
BT:                                            See 3.3.6.1.  (line  722)
C <1>:                                         See 3.3.10.   (line 1016)
C:                                             See 3.3.7.    (line  865)
card deck:                                     See 2.1.      (line  122)
command file:                                  See 3.4.      (line 1129)
CONTINUE <1>:                                  See 3.3.10.   (line 1015)
CONTINUE:                                      See 3.3.7.    (line  865)
cross-reference:                               See 2.2.      (line  290)
cross-reference, --cross-reference option, description:See 2.2.
                                                             (line  290)
cross-reference, --cross-reference option, summary:See 2.4.  (line  366)
D:                                             See 3.3.6.2.  (line  754)
d, -d short option, described:                 See 4.        (line 1208)
debug-gram, --debug-gram option, summary:      See 2.4.      (line  372)
debug-lex, --debug-lex option, summary:        See 2.4.      (line  375)
deck:                                          See 2.1.      (line  122)
DELETE <1>:                                    See 3.3.10.   (line 1008)
DELETE:                                        See 3.3.6.2.  (line  754)
devices, assigning files to:                   See 3.2.      (line  457)
devices, binding:                              See 3.2.      (line  457)
DIS:                                           See 3.3.6.3.  (line  787)
DISABLE <1>:                                   See 3.3.10.   (line 1021)
DISABLE:                                       See 3.3.6.3.  (line  787)
DISASSEMBLE <1>:                               See 3.3.10.   (line 1028)
DISASSEMBLE:                                   See 3.3.9.    (line  960)
DM:                                            See 3.3.10.   (line 1048)
DR:                                            See 3.3.10.   (line 1042)
DU:                                            See 3.3.10.   (line 1036)
DUMP <1>:                                      See 3.3.10.   (line 1035)
DUMP:                                          See 3.3.9.    (line  904)
DUMP MEMORY:                                   See 3.3.9.    (line  909)
DUMP REGISTERS:                                See 3.3.9.    (line  943)
dump, --dump option, described:                See 4.        (line 1208)
ENA:                                           See 3.3.6.3.  (line  792)
ENABLE <1>:                                    See 3.3.10.   (line 1053)
ENABLE:                                        See 3.3.6.3.  (line  792)
executing MIX programs:                        See 3.2.      (line  435)
force, --force option, summary:                See 2.4.      (line  347)
GO <1>:                                        See 3.3.10.   (line 1060)
GO:                                            See 3.3.5.    (line  664)
hello.mix:                                     See 2.        (line   99)
HELP <1>:                                      See 3.3.10.   (line 1064)
HELP:                                          See 3.3.2.    (line  577)
help, --help option, summary <1>:              See 3.5.      (line 1183)
help, --help option, summary:                  See 2.4.      (line  384)
I:                                             See 3.3.6.4.  (line  808)
IGNORE <1>:                                    See 3.3.10.   (line 1071)
IGNORE:                                        See 3.3.6.4.  (line  808)
implementation, MIX machine:                   See 3.1.      (line  406)
INFO:                                          See 3.3.10.   (line 1077)
INFO BREAK:                                    See 3.3.6.5.  (line  827)
INFO IO:                                       See 3.3.4.    (line  618)
l, -l short option, :                          See 2.2.      (line  192)
l, -l short option, described:                 See 4.        (line 1214)
LB:                                            See 3.3.10.   (line 1079)
LI:                                            See 3.3.10.   (line 1088)
LIST:                                          See 3.3.10.   (line 1078)
LIST IO:                                       See 3.3.4.    (line  618)
list, --list option, :                         See 2.2.      (line  192)
list, --list option, described:                See 4.        (line 1214)
list, --list option, summary:                  See 2.4.      (line  333)
list-file, --list-file option, :               See 2.2.      (line  203)
list-file, --list-file option, summary:        See 2.4.      (line  342)
listing:                                       See 2.2.      (line  211)
MIX simulator:                                 See 3.        (line  395)
mixal:                                         See 2.        (line   94)
mixrun:                                        See 4.        (line 1194)
mixsim:                                        See 3.        (line  395)
mixsim, running:                               See 3.2.      (line  435)
NEXT <1>:                                      See 3.3.10.   (line 1094)
NEXT:                                          See 3.3.7.    (line  877)
no-dump, --no-dump option, described:          See 4.        (line 1212)
o, -o short option, description:               See 2.1.      (line  182)
output, --output option, description:          See 2.1.      (line  182)
output, --output option, summary:              See 2.4.      (line  352)
P:                                             See 3.3.6.4.  (line  812)
PASSCOUNT <1>:                                 See 3.3.10.   (line 1099)
PASSCOUNT:                                     See 3.3.6.4.  (line  812)
program listing:                               See 2.2.      (line  211)
QUIT <1>:                                      See 3.3.10.   (line 1114)
QUIT:                                          See 3.3.3.    (line  592)
r, -r short option, :                          See 2.3.      (line  309)
raw object output:                             See 2.3.      (line  309)
raw-output, --raw-output option, :             See 2.3.      (line  309)
raw-output, --raw-output option, summary:      See 2.4.      (line  359)
RUN <1>:                                       See 3.3.10.   (line 1061)
RUN:                                           See 3.3.5.    (line  664)
running mixsim:                                See 3.2.      (line  435)
SHELL <1>:                                     See 3.3.10.   (line 1117)
SHELL:                                         See 3.3.8.    (line  892)
simulator:                                     See 3.        (line  395)
SO:                                            See 3.3.10.   (line 1108)
SOURCE <1>:                                    See 3.4.      (line 1139)
SOURCE:                                        See 3.3.10.   (line 1107)
startup file:                                  See 3.4.      (line 1153)
STEP <1>:                                      See 3.3.10.   (line 1121)
STEP:                                          See 3.3.7.    (line  883)
Symbol listing:                                See 2.2.      (line  248)
t, -t short option, description:               See 3.3.      (line  469)
TB <1>:                                        See 3.3.10.   (line 1005)
TB:                                            See 3.3.6.1.  (line  722)
terminal mode, mixsim:                         See 3.3.      (line  469)
terminal, --terminal option, description:      See 3.3.      (line  469)
terminal, --terminal option, summary:          See 3.5.      (line 1177)
U <1>:                                         See 3.3.10.   (line 1030)
U:                                             See 3.3.9.    (line  960)
UNASM <1>:                                     See 3.3.10.   (line 1029)
UNASM:                                         See 3.3.9.    (line  960)
version, --version option, summary <1>:        See 3.5.      (line 1187)
version, --version option, summary:            See 2.4.      (line  388)
x, -x short option, description:               See 2.2.      (line  290)
xref, --xref option, description:              See 2.2.      (line  290)
xref, --xref option, summary:                  See 2.4.      (line  365)