74HC165 serial register reading with perl

[rkrasowski]

Hi Perl Monks, that may be the silly question. I am trying to read data from 74HC165 which is PISO serial register. How effective (fast) would be to read it using Perl? Any code examples? Thanks like always Robert

[stevieb]

Is this for a Raspberry Pi? My RPi::WiringPi handles this shift register if on a Pi. See that linked documentation and associated FAQ for full details:

use RPi::WiringPi;
use RPi::Const qw(:all);
 
my $pi = RPi::WiringPi->new;

my ($base, $num_pins, $data, $clk, $latch)
  = (100, 8, 5, 6, 13);
 
$pi->shift_register(
    $base, $num_pins, $data, $clk, $latch
);
 
# now we can access the new 8 pins of the
# register commencing at new pin 100-107
 
for (100..107){
    my $pin = $pi->pin($_);
    $pin->write(HIGH);
}

Update: Whoops, I misread the IC device number. My code is for a 74HC595 (output) not a 74HC165 (input). Sorry for the noise.

[rkrasowski]

Thanks, will check module tomorrow and let you know how things are. Now I know where to start. I ordered PCB and 74HC165, expect to get it on few days. Will try real example at that time. Thanks Robert

[haukex]

How is this IC connected to the system? If you're working on a Raspberry Pi, you might want to look at stevieb's RPi:: series of modules, which includes RPi::SPI, RPi::Serial, and RPi::WiringPi.

Update: Fixed missing links.

[stevieb]

Thanks haukex, unfortunately after I posted I realized that the IC in question here is parallel input, where I have only got code for the parallel output register.

I'll put this chip on my list now though.