Try 

$x = 25;
while ($x>0) {
 sleep(1);
 $ob->write("\xFE\x90\xFF\x00" . chr( $x * 10 ) );
 $ob->write_drain;
 $x--;
}

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re: Casting magic - how to write numbers to the serial port by BrowserUk
in thread Casting magic - how to write numbers to the serial port by ehud42

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