module Beaglebone

This is the main module for this gem. You generally do not want to call these methods directly.

Constants

I2CS: I2C device hash
PINS: Hash of pins and their uses
SPIS: SPI device hash
TREES: Generic device trees
UARTS: UART device hash

Attributes

loaded_dtbs[RW]

pinmutex[RW]

pinstatus[RW]

Public Class Methods

check_valid_pin(pin, type = nil) click to toggle source

check if a pin of given type is valid

# File lib/beaglebone/beaglebone.rb, line 227
def check_valid_pin(pin, type = nil)
  #check to see if pin exists
  raise ArgumentError, "No such PIN: #{pin.to_s}" unless PINS[pin]

  if type
    raise StandardError, "Pin does not support #{type}: #{pin.to_s}" unless PINS[pin][type]
  end
end

cleanup() click to toggle source

cleanup all the things

# File lib/beaglebone/beaglebone.rb, line 275
def cleanup
  Beaglebone::AIN.cleanup
  Beaglebone::PWM.cleanup
  Beaglebone::GPIO.cleanup
  Beaglebone::UART.cleanup
  Beaglebone::I2C.cleanup
  Beaglebone::SPI.cleanup
end

delete_pin_status(pin, key = nil) click to toggle source

@private delete pin’s hash entry

# File lib/beaglebone/beaglebone.rb, line 199
def delete_pin_status(pin, key = nil)
  pinmutex.synchronize do
    if key.nil?
      pinstatus.delete(pin)
    else
      pinstatus[pin].delete(key) if pinstatus[pin]
    end
  end
end

device_tree_load(name, delay=0.25) click to toggle source

load a device tree

# File lib/beaglebone/beaglebone.rb, line 247
def device_tree_load(name, delay=0.25)
  return true if loaded_dtbs.include?(name)

  if device_tree_loaded?(name)
    loaded_dtbs << name
    return true
  end

  File.open("#{get_capemgr_dir}/slots", 'w') { |f| f.write(name) }
  sleep delay
  raise StandardError, "Unable to load device tree: #{name}" unless device_tree_loaded?(name)
  true
end

device_tree_loaded?(name) click to toggle source

check if device tree is loaded

# File lib/beaglebone/beaglebone.rb, line 242
def device_tree_loaded?(name)
  !!File.open("#{get_capemgr_dir}/slots").read.match(/,#{name}$/)
end

device_tree_unload(name) click to toggle source

unload a device tree, return false if not loaded, return true if it unloads

# File lib/beaglebone/beaglebone.rb, line 262
def device_tree_unload(name)
  return false unless device_tree_loaded?(name)

  dtb_id = File.open("#{get_capemgr_dir}/slots", 'r').read.scan(/^ ?(\d+): .*?,#{name}/).flatten.first

  File.open("#{get_capemgr_dir}/slots", 'w') { |f| f.write("-#{dtb_id}") }

  raise StandardError, "Unable to unload device tree: #{name}" if device_tree_loaded?(name)

  true
end

disable_pin(pin) click to toggle source

disable pin

# File lib/beaglebone/beaglebone.rb, line 210
def disable_pin(pin)
  status = get_pin_status(pin)

  if status
    case status[:type]
      when :gpio
        Beaglebone::GPIO.disable_gpio_pin(pin)
      when :pwm
        Beaglebone::PWM.disable_pwm_pin(pin)
      else
        #we can't disable any other pin types at this time
        raise StandardError, "Cannot disable pin: #{pin} in #{status[:type]} mode"
    end
  end
end

get_capemgr_dir() click to toggle source

return capemgr directory

# File lib/beaglebone/beaglebone.rb, line 237
def get_capemgr_dir
  Dir.glob([ '/sys/devices/bone_capemgr.*', '/sys/devices/platform/bone_capemgr' ]).first
end

get_pin_status(pin, key = nil) click to toggle source

@private get hash entry for pin

# File lib/beaglebone/beaglebone.rb, line 178
def get_pin_status(pin, key = nil)
  pinmutex.synchronize do
    if key
      pinstatus[pin] ? pinstatus[pin][key] : nil
    else
      pinstatus[pin]
    end
  end
end

set_pin_status(pin, key, value) click to toggle source

@private set hash entry for pin

# File lib/beaglebone/beaglebone.rb, line 190
def set_pin_status(pin, key, value)
  pinmutex.synchronize do
    pinstatus[pin]    ||= {}
    pinstatus[pin][key] = value
  end
end