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Hello there,
when i'm executing following script
use Device::ParallelPort;
my $port = Device::ParallelPort->new('auto:1');
print ord($port->get_byte(0))."\n";
$port->set_byte(0,chr(0));
print ord($port->get_byte(0))."\n";
&set_DIR('r');
print ord($port->get_byte(0))."\n";
&set_DIR('w');
$port->set_byte(0,chr(0));
print ord($port->get_byte(0))."\n";
$port->set_byte(0,chr(0));
print ord($port->get_byte(0))."\n";
sub set_DIR{
if ($_[0] eq 'r'){
print "r\n";
$port->set_bit(21,1); #read
print ord($port->get_byte(2))."\n";
}elsif ($_[0] eq 'w'){
print "w\n";
$port->set_bit(21,0); #write
print ord($port->get_byte(2))."\n";
}
}
i'm getting following result:
0
0
r
12
255
w
12
255
255
but i'm expecting that, when i'm writing a "0" to the data register in write mode, that i will also get back a "0" after reading the data register.
But this result looks like that, if the parallel port once is set in read mode, it's not possible to switch back to the write mode.
Does somebody know, what i'm doing wrong ?
Thanks in advance
Bernd
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