Here's some code that gets you close to what you want. It'll get you started... 
use strict;
use warnings;

while (<DATA>) {
    if (/0x([[:xdigit:]]+)/) {
        my $hexstr = $1;
        my $word;
        while ($hexstr =~ /(..)/g) {$word .= chr hex $1}
        s/0x$hexstr/$word/;
    }
    print;
}

__DATA__
blah0x4445434C41524520405420blah blah
foo zoo 75858

[download]

prints out: 

blahDECLARE @T lah blah
foo zoo 75858

[download]

You'll need to figure out how to deal with the 2nd "blah", whose 1st letter is a valid hex digit.

In reply to Re: convert several two digit hex characters to ascii by toolic
in thread convert several two digit hex characters to ascii by Anonymous Monk

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