Class: Phidgets::TextLCD::TextLCDScreens::TextLCDScreensRows

Inherits:
Object
  • Object
show all
Defined in:
lib/phidgets-ffi/text_lcd.rb

Overview

This class represents a row on a PhidgetTextLCD screen. All the properties of a row are stored and modified in this class.

Constant Summary collapse

Klass = 
Phidgets::FFI::CPhidgetTextLCD

Instance Method Summary collapse

Instance Method Details

#display_character(column, new_display_character) ⇒ Integer

Sets a single character for a specific column of a row, or raises an error.

example

lcd.screens[0].rows[1].display_character(4, 0x21)  #hex for ! in ASCII
lcd.screens[0].rows[1].display_character(5, 067)  #octal for 7 in ASCII

Parameters:

  • column (Integer) —

    column number

  • new_character (Integer) —

    new character(in hexadecimal, octal, etc..)

Returns:

  • (Integer) —

    returns the character, or raises an error.



202
203
204
205
206
207
208
 
# File 'lib/phidgets-ffi/text_lcd.rb', line 202

def display_character(column, new_display_character)
  if (Common.device_id(@handle).to_s == "textlcd_adapter")
	Klass.setScreen(@handle, @screen_index)
  end
  Klass.setDisplayCharacter(@handle, @row, column, new_display_character)
  new_display_character
end

#display_string=(new_display_string) ⇒ String

Sets the display string of a row, or raises an error.

example

lcd.screens[0].rows[1].display_string = "\x48"  #hex for H in ASCII
lcd.screens[0].rows[2].display_string = "\147"  #octal for g in ASCII

Parameters:

  • new_string (String) —

    string

Returns:

  • (String) —

    returns the display string, or raises an error.



186
187
188
189
190
191
192
 
# File 'lib/phidgets-ffi/text_lcd.rb', line 186

def display_string=(new_display_string)
  if (Common.device_id(@handle).to_s == "textlcd_adapter")
	Klass.setScreen(@handle, @screen_index)
  end
  Klass.setDisplayString(@handle, @row, new_display_string)
  new_display_string
end

#maximum_length ⇒ Integer

Returns the maximum length of a row, or raises an error.

Returns:

  • (Integer) —

    returns the maximum length of a row, or raises an error.



211
212
213
214
215
 
# File 'lib/phidgets-ffi/text_lcd.rb', line 211

def maximum_length
  ptr = ::FFI::MemoryPointer.new(:int)
  Klass.getColumnCount(@handle, ptr)
        ptr.get_int(0)
end