Class: OrigenLink::Server::Pin

Inherits:
Object
  • Object
show all
Defined in:
lib/origen_link/server/pin.rb

Overview

The server pin class is used to perform IO using the UDOO pins

Constant Summary

@@pin_setup = 
{
  in:  'in',
  out: 'out'
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ionumber, direction = :in) ⇒ Pin

Export the pin io files through the system and take control of the IO

This method will execute system command “echo #ionumber > /sys/class/gpio/export” to create the IO file interface. It will set the direction, initial pin state and initialize instance variables

Receives

ionumber - required, value indicating the pin number (BCM IO number,
           not the header pin number)
direction - optional, specifies the pin direction.  A pin is
            initialized as an input if a direction isn't specified.


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# File 'lib/origen_link/server/pin.rb', line 38

def initialize(ionumber, direction = :in)
  @ionumber = Integer(ionumber)
  @pin_dir_name = "#{Server.gpio_dir}/gpio#{@ionumber}/direction"
  @pin_val_name = "#{Server.gpio_dir}/gpio#{@ionumber}/value"
  if !File.exist?(@pin_dir_name)
    system("echo #{@ionumber} > #{Server.gpio_dir}/export")
    sleep 0.05
    if $CHILD_STATUS == 0
      @gpio_valid = true
    else
      @gpio_valid = false
    end
  else
    @gpio_valid = true
  end
  if @gpio_valid
    if File.writable?(@pin_dir_name)
      @pin_dir_obj = File.open(@pin_dir_name, 'w')
      update_direction(direction)
    else
      @gpio_valid = false
      puts "#{@pin_dir_name} is not writable. Fix permissions or run as super user."
    end
    @pin_val_obj = File.open(@pin_val_name, 'r+') if @gpio_valid
  end
  @pattern_data = ''
  @pattern_index = -1
  @response = 'W'
  @cycle_failure = false
  @data_is_drive = false
end

Instance Attribute Details

#gpio_valid ⇒ Object (readonly)

True if this pin exists in /sys/class/gpio after export. False otherwise.



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# File 'lib/origen_link/server/pin.rb', line 16

def gpio_valid
  @gpio_valid
end

#pattern_data ⇒ Object

This pin's vector data for the pattern cycle being executed



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# File 'lib/origen_link/server/pin.rb', line 18

def pattern_data
  @pattern_data
end

#pattern_index ⇒ Object

This pin's index in the vector data received from the plug-in app



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# File 'lib/origen_link/server/pin.rb', line 20

def pattern_index
  @pattern_index
end

#response ⇒ Object

This pin's response for the executing vector



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# File 'lib/origen_link/server/pin.rb', line 22

def response
  @response
end

Instance Method Details

#cycle_failure ⇒ Object

cycle_failure

returns a boolean indicating pass/fail status of this pin


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# File 'lib/origen_link/server/pin.rb', line 84

def cycle_failure
  if @response == 'W'
    true		# force failure if no operation performed
  else
    @cycle_failure
  end
end

#data_is_compare? ⇒ Boolean

data_is_compare?

returns whether the current pattern data is compare

Returns:

  • (Boolean) 


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# File 'lib/origen_link/server/pin.rb', line 78

def data_is_compare?
  !@data_is_drive
end

#data_is_drive? ⇒ Boolean

data_is_drive?

returns whether the current pattern data is drive

Returns:

  • (Boolean) 


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# File 'lib/origen_link/server/pin.rb', line 72

def data_is_drive?
  @data_is_drive
end

#destroy ⇒ Object

Close the file IO objects associated with this pin



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# File 'lib/origen_link/server/pin.rb', line 151

def destroy
  if @gpio_valid
    @pin_dir_obj.close
    @pin_val_obj.close
    # system("echo #{@ionumber} > /sys/class/gpio/unexport")
    # puts "pin #{@ionumber} is no longer exported"
  end
end

#in ⇒ Object

Reads and returns state of the pin.

If the pin is setup as an output, the direction will first be changed to input.



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# File 'lib/origen_link/server/pin.rb', line 180

def in
  if @gpio_valid
    if @direction == :out
      update_direction(:in)
    end
    # below is original read - slow to reopen every time
    # File.open(@pin_val_name, 'r') do |file|
    #  file.read#.chomp
    # end
    # end original read
    @pin_val_obj.pos = 0
    @pin_val_obj.getc
  end
end

#load_pattern_data(cycle) ⇒ Object

load_pattern_data

Grab this pin's data character from the pattern data


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# File 'lib/origen_link/server/pin.rb', line 94

def load_pattern_data(cycle)
  if @pattern_index > -1
    @pattern_data = cycle[@pattern_index]
    @response = 'W'
    @cycle_failure = false
    if @pattern_data == '1' || @pattern_data == '0'
      @data_is_drive = true
    else
      @data_is_drive = false
    end
  else
    @gpio_valid = false
  end
end

#out(value) ⇒ Object

Sets the output state of the pin.

If the pin is setup as an input, the direction will first be changed to output.



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# File 'lib/origen_link/server/pin.rb', line 165

def out(value)
  if @gpio_valid
    if @direction == :in
      update_direction(:out)
    end
    @pin_val_obj.write(value)
    @pin_val_obj.flush
  end
end

#process_event(operation, requested_action) ⇒ Object

process_event(event)

perform the requested pin operation and update the response (if required)


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# File 'lib/origen_link/server/pin.rb', line 111

def process_event(operation, requested_action)
  if operation == :drive
    if data_is_drive?
      if requested_action == 'data'
        out(@pattern_data)
        @response = @pattern_data
      else
        out(requested_action)
      end # requested_action == 'data'
    end # data_is_drive?
  end # operation == :drive
  if operation == :compare
    if data_is_compare?
      if requested_action == 'data'
        case self.in
          when '0'
            @cycle_failure = true if @pattern_data == 'H'
            if @pattern_data == 'X'
              @response = '.'
            else
              @response = 'L'
            end
          # end of when '0'
          when '1'
            @cycle_failure = true if @pattern_data == 'L'
            if @pattern_data == 'X'
              @response = '`'
            else
              @response = 'H'
            end
          # end of when '1'
          else
            @response = 'W'
        end # case
      end # requested_action == 'data'
    end # data_is_compare?
  end # operation == :compare
end

#to_s ⇒ Object

Returns 'OrigenLinPin' + io number



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# File 'lib/origen_link/server/pin.rb', line 213

def to_s
  'OrigenLinkPin' + @ionumber.to_s
end

#update_direction(direction) ⇒ Object

Sets the pin direction

Receives:

direction - specifies the pin direction.  Input is default.

Valid direction values:
  :in	-	input
  :out	-	output


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# File 'lib/origen_link/server/pin.rb', line 203

def update_direction(direction)
  if @gpio_valid
    @pin_dir_obj.pos = 0
    @pin_dir_obj.write(@@pin_setup[direction])
    @pin_dir_obj.flush
    @direction = direction
  end
end