mixal – MIX Assembler.
mixsim – MIX Simulator.
mixsim option summary.mixrunThis edition of the MIX Manual, last updated 30 October 2009, documents MIX Version 2.0.
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:
mixalA MIXAL assembler, i.e. a program which translates a MIXAL source file into a program that can be run on a MIX machine.
mixsimMIX 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.
mixrunA 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).
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
|
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 mixsim – MIX Simulator.. 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 |
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.
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.
mixal option summary. Usage:
mixal [options] [file]
|
The following table summarizes the available command line options:
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’.
See section Program Listing.
Set listing file name. Implies ‘--list’.
See mixal-list-file.
Force generating object deck (and, eventually, listing) even if there were errors during assembly.
Set output file name. By default, object deck is printed on the standard output.
See mixal-output.
Produce raw object output.
See section Raw Object Code..
Output a cross reference.
See mixal-xref.
Enable parser debugging output.
Enable lexical analyzer debugging output.
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.
Print a concise help summary.
Print program version and license information.
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.
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.
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:
mixsim stdin:
$ mixsim < hello.deck |
mixsim:
$ mixsim hello.deck |
$ 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 |
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.
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. See section Command Completion, for a detailed desctiption.
You can test if an abbreviation is valid by using it as an argument
to the help command (see section Obtaining On-line 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 (see section Command Files).
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 prior to compiling mix.
See Command Line Editing: (readline)Command Line Editing section `Command Line Editing' in GNU Readline Library, 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
(see section 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 |
HELP? To obtain help about all available commands, type HELP.
HELP cmd? cmdWhen used with an argument, it displays usage summary for the given command verb, e.g.:
MIX> HELP ASGN ASGN <DEVICE> <FILE> |
QUITQ 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 (see section Stopping and Continuing),
or, if no program is being run, cancels the current input line.
ASGN device fileA device fileAssign 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 Listing Breakpoints.
The information is displayed in tabular form and contains the following columns:
Unit number.
I/O time per block.
Seek time.
Memory address for the pending I/O operation.
Device position for the pending I/O operation. This column is meaningful only for tape and disk devices.
Opcode or ‘N/A’, if no operation is pending.
Clock time when the I/O will occur. To examine the current clock time, see Listing Breakpoints.
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 |
GOGRUNREmulates MIX GO button.
This command does the following:
JMP to location ‘0000’ occurs. The
J-register is also set to 0.
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 (see section Deleting Breakpoints):
MIX> DELETE 2 |
In contrast, the following command deletes all breakpoints set at address 1000:
MIX> ADDRESS DELETE 1000 |
Breakpoints are set with the BREAK command (abbreviated
B).
BREAK locationB locationSet 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 locationBT locationTB locationSets 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 |
See section 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.
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:
MIX> DELETE |
MIX> DELETE 1 3 5 |
MIX> ADDRESS DELETE 1000 3000 |
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
(see section Listing Breakpoints).
DISABLE [number-list]DIS [number-list]Disable breakpoints, specified by number-list. If no arguments are given, disables all breakpoints.
ENABLE number-listENA number-listEnable 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.
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 countI number countSet ignore count for breakpoint number to count.
PASSCOUNT number countP number countSet 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 |
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. |
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).
CONTINUECContinue program execution, at the address where it last stopped.
A typical debugging technique is to set a breakpoint (see section Setting 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.
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.
DUMPDUDump 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 REGISTERSDRDump 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 |
For convenience, this section lists all available terminal commands in alphabetical order, along with a short description and a reference to their detailed description.
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. See section ADDRESS prefix.
Assign file to the given MIX device.
See section Assigning and Listing Devices.
Set a breakpoint at the given location. If TEMP is given,
set a temporary breakpoint, active for one pass only.
See section Breakpoints.
Shortcut for BREAK TEMP.
Delete specified breakpoints. num-list is a list of breakpoint
numbers or, if ADDRESS prefix is used, their addresses.
Without arguments, delete all breakpoints.
See section Deleting Breakpoints.
Continue program execution, at the address where it last stopped.
See section Stopping and Continuing.
Disable breakpoints. num-list is a list of breakpoint
numbers or, if ADDRESS prefix is used, their addresses.
Without arguments, disable all breakpoints.
See section Disabling and Enabling Breakpoints.
Dump a range of memory as MIX instructions.
See section DISASSEMBLE.
Dump MIX registers and memory contents.
See section Examining Data and Registers.
Dump contents of MIX registers.
See section DUMP REGISTERS.
Dump MIX memory.
See section DUMP MEMORY.
Enable breakpoints. num-list is a list of breakpoint
numbers or, if ADDRESS prefix is used, their addresses.
Without arguments, enable all breakpoints.
See section ENABLE.
Run a program. See section Running a Program.
Display a short usage summary about command-verb. Without arguments, display all available commands.
See section Obtaining On-line Help.
Set ignore count for breakpoint number to count.
number is a breakpoint number or, if ADDRESS prefix is
used, its address.
See section IGNORE.
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.
See section Listing Breakpoints.
Without arguments, list all devices. With a numeric argument, show information about that particular device.
See section INFO IO.
Execute next count (default is 1) instructions and stop again.
See section NEXT.
Set pass count for breakpoint number to count.
number is a breakpoint number or, if ADDRESS prefix is
used, its address.
See section PASSCOUNT.
Execute the command file filename.
See section Command Files, for more information about command files and their execution.
Quit the terminal. See section Quitting the Terminal.
Execute given shell command. See section Executing Shell Commands..
Execute next count (default is 1) instructions and stop again. If a function call is encountered, descend into the function.
See section STEP.
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 filenameSO filenameExecute 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 (see section Terminal Mode and Debugger.), 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 |
mixsim option summary. This section summarizes mixsim command line options.
Usage:
mixsim [options] [deck-file]
|
Assign file to the MIX device dev.
See section Executing MIX Programs..
Run in terminal mode.
See section Terminal Mode and Debugger..
Print a concise help summary.
Print program version and license information.
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.
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 1.3, 3 November 2008
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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.
This is a general index of all issues discussed in this manual.
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A B C D E F G H I L M N O P Q R S T U V X |
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It will be implemented in future releases
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