https://github.com/spider-gazelle/gpio.cr

crystal lang bindings for linux gpiod
https://github.com/spider-gazelle/gpio.cr

Last synced: about 2 months ago
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crystal lang bindings for linux gpiod

• Host: GitHub
• URL: https://github.com/spider-gazelle/gpio.cr
• Owner: spider-gazelle
• License: mit
• Created: 2023-10-08T04:35:41.000Z (12 months ago)
• Default Branch: main
• Last Pushed: 2024-05-23T13:47:50.000Z (4 months ago)
• Last Synced: 2024-07-25T18:33:28.705Z (about 2 months ago)
• Language: Crystal
• Size: 6.84 KB
• Stars: 1
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-crystal - gpio.cr - Bindings for the gpiod library (general purpose IO control and feedback) (C bindings)

README

        
# gpio

bindings for linux gpiod, a user space interface for general purpose IO control

## Installation

ensure the development dependencies are installed: `sudo apt install libgpiod-dev`

1. Add the dependency to your `shard.yml`:

   ```yaml

   dependencies:

     gpio:

       github: spider-gazelle/gpio.cr

   ```

2. Run `shards install`

## Usage

You can list the various chips available on a system by running `gpioinfo` this will list chips and IO line details.

```crystal

require "gpio"

GPIO.default_consumer = "my app"

all_chips = GPIO::Chip.all

# or if you know the name

chip = GPIO::Chip.new "gpiochip0"

chip.lines

# take control of a line and set it's state

line = chip.line(5)

line.name

line.request_output

line.set_high

line.high? # => true

sleep 0.5

line.set_low

line.high? # => false

# release the line once finished using

# this will also happen on garbage collection

line.release

```

You can also configure the line for input and wait for input events to occur

```crystal

require "gpio"

GPIO.default_consumer = "my app"

chip = GPIO::Chip.new "gpiochip0"

line = chip.line 0

# blocks here until this line is released

# so you might want to do this in a spawn etc

line.on_input_change do |input_is|

  case input_is

  in .rising?

    puts "input is high"

  in .falling?

    puts "input is low"

  end

end

```