I've got an update. Today I got a set of little patch cables in the mail and hooked up an old single-digit LED display to seven of the GPIO ports. I then added these subroutines to my library:
sub bar
{
my @bar = @_;
for my $pin (@pins)
{
Device::BCM2835::gpio_write( $pin, 0 );
}
Device::BCM2835::delay( 40 );
for my $pin (@pins)
{
my $val = shift @bar;
Device::BCM2835::gpio_write( $pin, 1 ) if $val == 1;
}
Device::BCM2835::delay( 240 );
}
sub bilanidin
{
while ($_ = lc shift)
{
print "$_\n";
bar( qw/1 0 1 0 1 0 1 1/ ) if /a/;
bar( qw/0 0 0 0 0 1 0 1/ ) if /b/;
bar( qw/1 0 1 1 0 1 1 1/ ) if /ch/;
bar( qw/1 0 0 0 1 1 0 0/ ) if /d/;
bar( qw/1 0 0 1 0 1 1 0/ ) if /e/;
bar( qw/1 0 0 0 1 0 0 1/ ) if /g/;
bar( qw/0 0 0 1 0 1 1 0/ ) if /[ijy]/;
bar( qw/1 0 0 1 1 0 1 0/ ) if /[kq]/;
bar( qw/0 0 1 1 1 1 0 0/ ) if /l/;
bar( qw/0 0 1 1 0 0 1/ ) if /m/;
bar( qw/0 0 1 1 1 0 0 1/ ) if /n/;
bar( qw/1 0 0 0 1 1 1 1/ ) if /o/;
bar( qw/0 0 1 1 0 1 1 0/ ) if /p/;
bar( qw/0 0 1 0 0 0 1 1/ ) if /r/;
bar( qw/0 0 1 1 1 0 1 0/ ) if /s/;
bar( qw/0 0 1 0 1 0 1 1/ ) if /t/;
bar( qw/0 0 1 0 0 0 1 0/ ) if /[huvw]/;
bar( qw/1 0 1 1 1 0 1 0/ ) if /x/;
bar( qw/0 0 0 1 0 0 1 1/ ) if /z/;
}
Device::BCM2835::delay( 400 );
bar( qw/0 0 0 0 0 0 0 0/ );
}
"Bilanidin" is a font designed by Marc Miller for the Traveller pencil-and-paper RPG. I adapted it to the display as closely as I could.
Now my little server can talk to me in bilanidin letters as well as Morse code. This is a lot of fun.