/ 
Hardware-Simulator-MIX-0.3
River stage zero No dependents
/ Hardware::Simulator::MIX

NAME

Hardware::Simulator::MIX - Knuth's famous virtual machine

SYNOPSIS

use Hardware::Simulator::MIX;

my $mix = new Hardware::Simulator::MIX;
while (!$mix->is_halted()) {
    $mix->step();
}

DESCRIPTION

This implementation includes the GO button and the default loader is the answer to Exercise 1.3 #26.

Trace execution count and time for every instruction.

For detailed architecture information, search MIX in wikipedia.

CONSTRUCTOR

$mix = Hardware::Simulator::MIX->new(%options);

This method constructs a new Hardware::Simulator::MIX object and returns it. Key/value pair arguments may be provided to set up the initial state. The following options correspond to attribute methods described below:

KEY                     DEFAULT
-----------             --------------------
max_byte                64
timeunit                5   (microseconds)

MACHINE STATE

Registers

Accessing registers:

$mix->{reg_name}

It is a reference to a MIX word. Available registers are listed below:

REGNAME                FORMAT
-----------            -----------------------
rA                     [?, ?, ?, ?, ?, ?]
rX                     [?, ?, ?, ?, ?, ?]
rI1                    [?, 0, 0, 0, ?, ?]
rI1                    [?, 0, 0, 0, ?, ?]
rI2                    [?, 0, 0, 0, ?, ?]
rI3                    [?, 0, 0, 0, ?, ?]
rI4                    [?, 0, 0, 0, ?, ?]
rI5                    [?, 0, 0, 0, ?, ?]
rI6                    [?, 0, 0, 0, ?, ?]
rI6                    [?, 0, 0, 0, ?, ?]
rJ                     [?, 0, 0, 0, ?, ?]
pc                     Integer in 0..3999

Note: the names are case sensitive.

$mix->get_reg($reg_name);
$mix->set_reg($reg_name, $wref);
Memory
$mix->read_mem($loc);
$mix->read_mem($loc, $l);
$mix->read_mem($loc, $l, $r);

Return a MIX word from memory. $loc must be among 0 to 3999. If field spec $l and $r are missing, they are 0 and 5; If $r is missing, it is same as $l.

$mix->read_mem(4);

equals to

$mix->read_mem(4,4);

Write memory.

$mix->write_mem($loc, $wref, $l, $r);
Status

$mix->get_cmp_flag() returns an integer. If the returned value is negative, the flag is "L"; if the return value is positive, the flag is "G"; if the return value is 0, the flag is "E".

$mix->get_overflow() return 0 if there is no overflow. return 1 if overflow happen.

$mix->get_current_time() returns the current mix running time in time units since the last reset.

$mix->is_halted() returns 1 if the machine halts.

TRACING

Get the execution count of an instruction
$mix->get_exec_count($loc);
Get the time spent on an instruction

The result is in MIX time units.

$mix->get_exec_time($loc);

EXECUTION

$mix->reset()
$mix->step()
$mix->go()

IO DEVICES

General information about MIX io devices.

Card reader and punch
Printer
Tape
Disk and drum
Paper tape and typewriter

AUTHOR

Chaoji Li<lichaoji@gmail.com>

http://www.litchie.net

Please feel free to send a email to me if you have any question.

SEE ALSO

The package also includes a mixasm.pl which assembles MIXAL programs. Usage:

perl mixasm.pl <yourprogram>

This command will generate a .crd file which is a card deck to feed into the mixsim.pl. Typical usage:

perl mixsim.pl <yourprogram.crd>

Then type 'h' at the command line so you can see a list of commands. You can load a MIX program into the machine and see it run.