Spi

Crystal interface to the SPI driver on the Raspberry PI. This uses the userland IOCTL SPI interface to send and receive data on the raspberry pi.

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     spi:
       github: sleepinginsomniac/spi

2. Run shards install

Usage

require "spi"

device = Spi::Device.new("/dev/spidev0.0")
device.mode = Spi::Mode::MODE_1
device.bits_per_word = 8_u8
device.baud = 800_000_u32 # 800KHz or whatever is supported

# Send 1 byte
data = Slice[0xAAu8] # etc.
device.send(data)

# Receive 10 bytes
data = Slice(UInt8).new(10)
device.receive(data)

# Duplex data:
dout = Slice[0xAAu8]
din  = Slice(UInt8).new(1)
device.transfer(send: dout, recv: din)

Development

TODO: Write development instructions here

Contributing

1. Fork it (https://github.com/sleepinginsomniac/spi/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Alex Clink - creator and maintainer