Class: Aio::Board

Inherits:
Object
  • Object
show all
Defined in:
lib/aio/board.rb

Overview

This is the main class that communicates with the Arduino board.

It implements several mechanisms like ACK/NAK for confirming command execution and redundancy checks to ensure data integrity.

Instance Method Summary collapse

Constructor Details

#initialize(port) {|self| ... } ⇒ Board

Returns a new instance of Board.

Examples:

Modes of initialization

# explicit
board = Aio::Board.new("/dev/ttyUSB1")

# block mode (closes the connection at the end)
Aio::Board.new("/dev/ttyUSB0") do |board|
  # code...
end

Parameters:

  • port (String) —

    the device/address used for communication.

Yields:

  • (self) —

    an optional block of code to execute.

Raises:

  • (DeviceError) —

    when the serial port is unavailable.



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# File 'lib/aio/board.rb', line 24

def initialize(port)
	@serial = SerialPort.new(port, BAUDRATE, 8, 1, SerialPort::NONE)
rescue Errno::ENOENT
	raise Aio::DeviceError, "Unavailable serial port at address => '#{port}'"
else
	@serial.flow_control = SerialPort::NONE
	@serial.read_timeout = TIMEOUT
	@serial.sync = true
	
	if block_given?
		yield(self)
		close
	end
end

Instance Method Details

#analogRead(pin) ⇒ Integer?

Reads the value from a specified analog pin.

Parameters:

  • pin (Integer) —

    pin number (as stated in the board).

Returns:

  • (Integer, nil) —

    an integer between 0 and 1023 or nil on error.

Raises:



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# File 'lib/aio/board.rb', line 99

def analogRead(pin)
	try(nil) {
		sendCMD [4, pin, empty]
		onACK do
			onData(4) do |bytes|
				bytes[0] + (bytes[1] << 8)
			end
		end
	}
end

#analogReference(type) ⇒ Boolean

Configures the reference voltage used for analog input.

Parameters:

Returns:

  • (Boolean) —

    if the command was successful.

Raises:



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# File 'lib/aio/board.rb', line 130

def analogReference(type)
	try(false) {
		sendCMD [6, type, empty]
		onACK {true}
	}
end

#analogWrite(pin, value) ⇒ Boolean

Writes an analog value (PWM wave) to a pin.

Parameters:

  • pin (Integer) —

    pin number (as stated in the board).

  • value (Integer) —

    an integer between 0 (always off) and 255 (always on).

Returns:

  • (Boolean) —

    if the command was successful.

Raises:



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# File 'lib/aio/board.rb', line 117

def analogWrite(pin, value)
	try(false) {
		sendCMD [5, pin, value]
		onACK {true}
	}
end

#close ⇒ nil

Closes the connection with the board.

Returns:

  • (nil) 


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# File 'lib/aio/board.rb', line 43

def close
	@serial.close
	nil
end

#digitalRead(pin) ⇒ Integer?

Reads the value from a specified digital pin.

Parameters:

  • pin (Integer) —

    pin number (as stated in the board).

Returns:

  • (Integer, nil) —

    HIGH (1), LOW (0) or nil on error.

Raises:



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# File 'lib/aio/board.rb', line 68

def digitalRead(pin)
	try(nil) {
		sendCMD [2, pin, empty]
		onACK do
			onData(4) do |bytes|
				bytes[0]
			end
		end
	}
end

#digitalWrite(pin, state) ⇒ Boolean

Writes a HIGH (1) or a LOW (0) value to a digital pin.

Parameters:

  • pin (Integer) —

    pin number (as stated in the board).

  • state (Integer) —

    HIGH (1) or LOW (0).

Returns:

  • (Boolean) —

    if the command was successful.

Raises:



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# File 'lib/aio/board.rb', line 86

def digitalWrite(pin, state)
	try(false) {
		sendCMD [3, pin, state]
		onACK {true}
	}
end

#millis ⇒ Integer?

Returns the number of milliseconds since the Arduino board began running the current program.

Returns:

  • (Integer, nil) —

    a 32bit integer or nil on error.

Raises:



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# File 'lib/aio/board.rb', line 142

def millis
	try(nil) {
		sendCMD [7, empty, empty]
		onACK do
			onData(4) do |bytes|
				bytes[0] + (bytes[1] << 8) + (bytes[2] << 16) + (bytes[3] << 24)
			end
		end
	}
end

#pinMode(pin, mode) ⇒ Boolean

Sets the mode of operation for a specific pin.

Parameters:

  • pin (Integer) —

    pin number (as stated in the board).

  • mode (Integer) —

    mode of operation: INPUT, OUTPUT or INPUT_PULLUP.

Returns:

  • (Boolean) —

    if the command was successful.

Raises:



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# File 'lib/aio/board.rb', line 55

def pinMode(pin, mode)
	try(false) {
		sendCMD [1, pin, mode]
		onACK {true}
	}
end

#ready? ⇒ Boolean

Tells if the board is ready.

Returns:

  • (Boolean)

Raises:



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# File 'lib/aio/board.rb', line 158

def ready?
	try(false) {
		sendCMD [8, empty, empty]
		onACK {true}
	}
end