/ 
RPi-WiringPi-0.03
River stage one • 1 direct dependent • 1 total dependent
/ RPi::WiringPi

NAME

RPi::WiringPi - Perl interface to Raspberry Pi's board and GPIO pin functionality

SYNOPSIS

use RPi::WiringPi;
use RPi::WiringPi::Constant qw(:all);

my $pi = RPi::WiringPi->new;

my $board = $pi->board;

print "Raspberry Pi board revision: ". $board->rev ."\n";

my $gpio_pin_1 = $pi->pin(1);
my $gpio_pin_2 = $pi->pin(2);

$gpio_pin_1->mode(INPUT);
$gpio_pin_2->mode(OUTPUT);

my $pin1_on = $gpio_pin_1->read;

if ($pin1_on){
    $gpio_pin_2->write(HIGH);
}

$pi->cleanup;

DESCRIPTION

WARNING: Until version 1.00 is released, the API and other functionality of this module may change, and things may break from time-to-time.

This is the root module for the RPi::WiringPi system. It interfaces to a Raspberry Pi board, its accessories and its GPIO pins via the wiringPi library through the Perl wrapper RPi::WiringPi::Core module.

There are a basic set of constants that can be imported. See RPi::WiringPi::Constant.

wiringPi must be installed prior to installing/using this module.

By default, we use wiringPi's interpretation of GPIO pin mapping. See new method to change this behaviour.

OPERATIONAL METHODS

new(%args)

Returns a new RPi::WiringPi object.

Parameters:

setup => $value

Optional. This option specifies which GPIO pin mapping (numbering scheme) to use. wiringPi for wiringPi's mapping, physical or system to use the pin numbers labelled on the board itself, or gpio use the Broadcom (BCM) pin numbers.

See wiringPi setup reference for important details on the differences.

fatal_exit => $bool

Optional: We trap all die() calls and clean up for safety reasons. If a call to die() is trapped, by default, we clean up, and then exit(). Set fatal_exit to false (0) to perform the cleanup, and then continue running your script. This is for unit testing purposes only.

board()

Returns a RPi::WiringPi::Board object which has access to various attributes of the Raspberry Pi physical board itself.

pin($pin_num)

Returns a RPi::WiringPi::Pin object, mapped to a specified GPIO pin.

Parameters:

$pin_num

Mandatory: The pin number to attach to.

cleanup()

Resets all registered pins back to default settings (off). It's important that this method be called in each application.

HELPER METHODS

These methods aren't normally needed by end-users. They're available for those who want to write their own libraries.

pin_map()

Returns the current pin mapping in use. Returns "NULL" it has not yet been set.

registered_pins()

Returns an array of RPi::WiringPi::Pin objects that are currently registered, and deemed to be in use.

register_pin($pin_obj)

Registers a GPIO pin within the system for error checking, and proper resetting of the pins in use when required.

Parameters:

$pin_obj

Mandatory: An object instance of RPi::WiringPi::Pin class.

unregister_pin($pin_obj)

Exactly the opposite of register_pin().

ENVIRONMENT VARIABLES

There are certain environment variables available to aid in testing on non-Raspberry Pi boards.

NO_BOARD

Set to true, will bypass the wiringPi board checks. False will re-enable them.

IMPORTANT NOTES

wiringPi must be installed prior to installing/using this module.
By default, we use wiringPi's interpretation of GPIO pin mapping. See new method to change this behaviour.
This module hijacks fatal errors with $SIG{__DIE__}, as well as $SIG{INT}. This is so that in the case of a fatal error, the Raspberry Pi pins are never left in an inconsistent state. By default, we trap the die(), reset all pins to their default (INPUT, LOW), then we exit(). Look at the fatal_exit param in new() to change the behaviour.

AUTHOR

Steve Bertrand, <steveb@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2016 by Steve Bertrand

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.18.2 or, at your option, any later version of Perl 5 you may have available.