So the key information you need is that you need to use the bit operators to manipulate the bits in each byte to extract the interesting bit fields. In particular use & (bitwise and) and a bit mask to isolate bit fields, and use the bitwise shift operators >> and << to move fields of bits about. For example, to isolate the op code you'd do something like:

use strict;
use warnings;

my $byte = 0b00100100;
my $opCode = ($byte & 0b11100000) >> 5;

printf "Opcode is 0x%02X\n", $opCode;

[download]

Prints:

Opcode is 0x01

[download]

See perlop for details about the various Perl operators.

True laziness is hard work

In reply to Re^3: Parsing through instructions by GrandFather
in thread Parsing through instructions by DaveMonk

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