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Diffstat (limited to 'Adafruit_Python_CharLCD/Adafruit_CharLCD/Adafruit_CharLCD.py')
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diff --git a/Adafruit_Python_CharLCD/Adafruit_CharLCD/Adafruit_CharLCD.py b/Adafruit_Python_CharLCD/Adafruit_CharLCD/Adafruit_CharLCD.py new file mode 100755 index 0000000..b900799 --- /dev/null +++ b/Adafruit_Python_CharLCD/Adafruit_CharLCD/Adafruit_CharLCD.py @@ -0,0 +1,477 @@ +# Copyright (c) 2014 Adafruit Industries +# Author: Tony DiCola +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +# THE SOFTWARE. +import time + +import Adafruit_GPIO as GPIO +import Adafruit_GPIO.I2C as I2C +import Adafruit_GPIO.MCP230xx as MCP +import Adafruit_GPIO.PWM as PWM + + +# Commands +LCD_CLEARDISPLAY = 0x01 +LCD_RETURNHOME = 0x02 +LCD_ENTRYMODESET = 0x04 +LCD_DISPLAYCONTROL = 0x08 +LCD_CURSORSHIFT = 0x10 +LCD_FUNCTIONSET = 0x20 +LCD_SETCGRAMADDR = 0x40 +LCD_SETDDRAMADDR = 0x80 + +# Entry flags +LCD_ENTRYRIGHT = 0x00 +LCD_ENTRYLEFT = 0x02 +LCD_ENTRYSHIFTINCREMENT = 0x01 +LCD_ENTRYSHIFTDECREMENT = 0x00 + +# Control flags +LCD_DISPLAYON = 0x04 +LCD_DISPLAYOFF = 0x00 +LCD_CURSORON = 0x02 +LCD_CURSOROFF = 0x00 +LCD_BLINKON = 0x01 +LCD_BLINKOFF = 0x00 + +# Move flags +LCD_DISPLAYMOVE = 0x08 +LCD_CURSORMOVE = 0x00 +LCD_MOVERIGHT = 0x04 +LCD_MOVELEFT = 0x00 + +# Function set flags +LCD_8BITMODE = 0x10 +LCD_4BITMODE = 0x00 +LCD_2LINE = 0x08 +LCD_1LINE = 0x00 +LCD_5x10DOTS = 0x04 +LCD_5x8DOTS = 0x00 + +# Offset for up to 4 rows. +LCD_ROW_OFFSETS = (0x00, 0x40, 0x14, 0x54) + +# Char LCD plate GPIO numbers. +LCD_PLATE_RS = 15 +LCD_PLATE_RW = 14 +LCD_PLATE_EN = 13 +LCD_PLATE_D4 = 12 +LCD_PLATE_D5 = 11 +LCD_PLATE_D6 = 10 +LCD_PLATE_D7 = 9 +LCD_PLATE_RED = 6 +LCD_PLATE_GREEN = 7 +LCD_PLATE_BLUE = 8 + +# Char LCD plate button names. +SELECT = 0 +RIGHT = 1 +DOWN = 2 +UP = 3 +LEFT = 4 + +# Char LCD backpack GPIO numbers. +LCD_BACKPACK_RS = 1 +LCD_BACKPACK_EN = 2 +LCD_BACKPACK_D4 = 3 +LCD_BACKPACK_D5 = 4 +LCD_BACKPACK_D6 = 5 +LCD_BACKPACK_D7 = 6 +LCD_BACKPACK_LITE = 7 + +class Adafruit_CharLCD(object): + """Class to represent and interact with an HD44780 character LCD display.""" + + def __init__(self, rs, en, d4, d5, d6, d7, cols, lines, backlight=None, + invert_polarity=True, + enable_pwm=False, + gpio=GPIO.get_platform_gpio(), + pwm=PWM.get_platform_pwm(), + initial_backlight=1.0): + """Initialize the LCD. RS, EN, and D4...D7 parameters should be the pins + connected to the LCD RS, clock enable, and data line 4 through 7 connections. + The LCD will be used in its 4-bit mode so these 6 lines are the only ones + required to use the LCD. You must also pass in the number of columns and + lines on the LCD. + + If you would like to control the backlight, pass in the pin connected to + the backlight with the backlight parameter. The invert_polarity boolean + controls if the backlight is one with a LOW signal or HIGH signal. The + default invert_polarity value is True, i.e. the backlight is on with a + LOW signal. + + You can enable PWM of the backlight pin to have finer control on the + brightness. To enable PWM make sure your hardware supports PWM on the + provided backlight pin and set enable_pwm to True (the default is False). + The appropriate PWM library will be used depending on the platform, but + you can provide an explicit one with the pwm parameter. + + The initial state of the backlight is ON, but you can set it to an + explicit initial state with the initial_backlight parameter (0 is off, + 1 is on/full bright). + + You can optionally pass in an explicit GPIO class, + for example if you want to use an MCP230xx GPIO extender. If you don't + pass in an GPIO instance, the default GPIO for the running platform will + be used. + """ + # Save column and line state. + self._cols = cols + self._lines = lines + # Save GPIO state and pin numbers. + self._gpio = gpio + self._rs = rs + self._en = en + self._d4 = d4 + self._d5 = d5 + self._d6 = d6 + self._d7 = d7 + # Save backlight state. + self._backlight = backlight + self._pwm_enabled = enable_pwm + self._pwm = pwm + self._blpol = not invert_polarity + # Setup all pins as outputs. + for pin in (rs, en, d4, d5, d6, d7): + gpio.setup(pin, GPIO.OUT) + # Setup backlight. + if backlight is not None: + if enable_pwm: + pwm.start(backlight, self._pwm_duty_cycle(initial_backlight)) + else: + gpio.setup(backlight, GPIO.OUT) + gpio.output(backlight, self._blpol if initial_backlight else not self._blpol) + # Initialize the display. + self.write8(0x33) + self.write8(0x32) + # Initialize display control, function, and mode registers. + self.displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF + self.displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_2LINE | LCD_5x8DOTS + self.displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT + # Write registers. + self.write8(LCD_DISPLAYCONTROL | self.displaycontrol) + self.write8(LCD_FUNCTIONSET | self.displayfunction) + self.write8(LCD_ENTRYMODESET | self.displaymode) # set the entry mode + self.clear() + + def home(self): + """Move the cursor back to its home (first line and first column).""" + self.write8(LCD_RETURNHOME) # set cursor position to zero + self._delay_microseconds(3000) # this command takes a long time! + + def clear(self): + """Clear the LCD.""" + self.write8(LCD_CLEARDISPLAY) # command to clear display + self._delay_microseconds(3000) # 3000 microsecond sleep, clearing the display takes a long time + + def set_cursor(self, col, row): + """Move the cursor to an explicit column and row position.""" + # Clamp row to the last row of the display. + if row > self._lines: + row = self._lines - 1 + # Set location. + self.write8(LCD_SETDDRAMADDR | (col + LCD_ROW_OFFSETS[row])) + + def enable_display(self, enable): + """Enable or disable the display. Set enable to True to enable.""" + if enable: + self.displaycontrol |= LCD_DISPLAYON + else: + self.displaycontrol &= ~LCD_DISPLAYON + self.write8(LCD_DISPLAYCONTROL | self.displaycontrol) + + def show_cursor(self, show): + """Show or hide the cursor. Cursor is shown if show is True.""" + if show: + self.displaycontrol |= LCD_CURSORON + else: + self.displaycontrol &= ~LCD_CURSORON + self.write8(LCD_DISPLAYCONTROL | self.displaycontrol) + + def blink(self, blink): + """Turn on or off cursor blinking. Set blink to True to enable blinking.""" + if blink: + self.displaycontrol |= LCD_BLINKON + else: + self.displaycontrol &= ~LCD_BLINKON + self.write8(LCD_DISPLAYCONTROL | self.displaycontrol) + + def move_left(self): + """Move display left one position.""" + self.write8(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT) + + def move_right(self): + """Move display right one position.""" + self.write8(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT) + + def set_left_to_right(self): + """Set text direction left to right.""" + self.displaymode |= LCD_ENTRYLEFT + self.write8(LCD_ENTRYMODESET | self.displaymode) + + def set_right_to_left(self): + """Set text direction right to left.""" + self.displaymode &= ~LCD_ENTRYLEFT + self.write8(LCD_ENTRYMODESET | self.displaymode) + + def autoscroll(self, autoscroll): + """Autoscroll will 'right justify' text from the cursor if set True, + otherwise it will 'left justify' the text. + """ + if autoscroll: + self.displaymode |= LCD_ENTRYSHIFTINCREMENT + else: + self.displaymode &= ~LCD_ENTRYSHIFTINCREMENT + self.write8(LCD_ENTRYMODESET | self.displaymode) + + def message(self, text): + """Write text to display. Note that text can include newlines.""" + line = 0 + # Iterate through each character. + for char in text: + # Advance to next line if character is a new line. + if char == '\n': + line += 1 + # Move to left or right side depending on text direction. + col = 0 if self.displaymode & LCD_ENTRYLEFT > 0 else self._cols-1 + self.set_cursor(col, line) + # Write the character to the display. + else: + self.write8(ord(char), True) + + def set_backlight(self, backlight): + """Enable or disable the backlight. If PWM is not enabled (default), a + non-zero backlight value will turn on the backlight and a zero value will + turn it off. If PWM is enabled, backlight can be any value from 0.0 to + 1.0, with 1.0 being full intensity backlight. + """ + if self._backlight is not None: + if self._pwm_enabled: + self._pwm.set_duty_cycle(self._backlight, self._pwm_duty_cycle(backlight)) + else: + self._gpio.output(self._backlight, self._blpol if backlight else not self._blpol) + + def write8(self, value, char_mode=False): + """Write 8-bit value in character or data mode. Value should be an int + value from 0-255, and char_mode is True if character data or False if + non-character data (default). + """ + # One millisecond delay to prevent writing too quickly. + self._delay_microseconds(1000) + # Set character / data bit. + self._gpio.output(self._rs, char_mode) + # Write upper 4 bits. + self._gpio.output_pins({ self._d4: ((value >> 4) & 1) > 0, + self._d5: ((value >> 5) & 1) > 0, + self._d6: ((value >> 6) & 1) > 0, + self._d7: ((value >> 7) & 1) > 0 }) + self._pulse_enable() + # Write lower 4 bits. + self._gpio.output_pins({ self._d4: (value & 1) > 0, + self._d5: ((value >> 1) & 1) > 0, + self._d6: ((value >> 2) & 1) > 0, + self._d7: ((value >> 3) & 1) > 0 }) + self._pulse_enable() + + def create_char(self, location, pattern): + """Fill one of the first 8 CGRAM locations with custom characters. + The location parameter should be between 0 and 7 and pattern should + provide an array of 8 bytes containing the pattern. E.g. you can easyly + design your custom character at http://www.quinapalus.com/hd44780udg.html + To show your custom character use eg. lcd.message('\x01') + """ + # only position 0..7 are allowed + location &= 0x7 + self.write8(LCD_SETCGRAMADDR | (location << 3)) + for i in range(8): + self.write8(pattern[i], char_mode=True) + + def _delay_microseconds(self, microseconds): + # Busy wait in loop because delays are generally very short (few microseconds). + end = time.time() + (microseconds/1000000.0) + while time.time() < end: + pass + + def _pulse_enable(self): + # Pulse the clock enable line off, on, off to send command. + self._gpio.output(self._en, False) + self._delay_microseconds(1) # 1 microsecond pause - enable pulse must be > 450ns + self._gpio.output(self._en, True) + self._delay_microseconds(1) # 1 microsecond pause - enable pulse must be > 450ns + self._gpio.output(self._en, False) + self._delay_microseconds(1) # commands need > 37us to settle + + def _pwm_duty_cycle(self, intensity): + # Convert intensity value of 0.0 to 1.0 to a duty cycle of 0.0 to 100.0 + intensity = 100.0*intensity + # Invert polarity if required. + if not self._blpol: + intensity = 100.0-intensity + return intensity + + +class Adafruit_RGBCharLCD(Adafruit_CharLCD): + """Class to represent and interact with an HD44780 character LCD display with + an RGB backlight.""" + + def __init__(self, rs, en, d4, d5, d6, d7, cols, lines, red, green, blue, + gpio=GPIO.get_platform_gpio(), + invert_polarity=True, + enable_pwm=False, + pwm=PWM.get_platform_pwm(), + initial_color=(1.0, 1.0, 1.0)): + """Initialize the LCD with RGB backlight. RS, EN, and D4...D7 parameters + should be the pins connected to the LCD RS, clock enable, and data line + 4 through 7 connections. The LCD will be used in its 4-bit mode so these + 6 lines are the only ones required to use the LCD. You must also pass in + the number of columns and lines on the LCD. + + The red, green, and blue parameters define the pins which are connected + to the appropriate backlight LEDs. The invert_polarity parameter is a + boolean that controls if the LEDs are on with a LOW or HIGH signal. By + default invert_polarity is True, i.e. the backlight LEDs are on with a + low signal. If you want to enable PWM on the backlight LEDs (for finer + control of colors) and the hardware supports PWM on the provided pins, + set enable_pwm to True. Finally you can set an explicit initial backlight + color with the initial_color parameter. The default initial color is + white (all LEDs lit). + + You can optionally pass in an explicit GPIO class, + for example if you want to use an MCP230xx GPIO extender. If you don't + pass in an GPIO instance, the default GPIO for the running platform will + be used. + """ + super(Adafruit_RGBCharLCD, self).__init__(rs, en, d4, d5, d6, d7, + cols, + lines, + enable_pwm=enable_pwm, + backlight=None, + invert_polarity=invert_polarity, + gpio=gpio, + pwm=pwm) + self._red = red + self._green = green + self._blue = blue + # Setup backlight pins. + if enable_pwm: + # Determine initial backlight duty cycles. + rdc, gdc, bdc = self._rgb_to_duty_cycle(initial_color) + pwm.start(red, rdc) + pwm.start(green, gdc) + pwm.start(blue, bdc) + else: + gpio.setup(red, GPIO.OUT) + gpio.setup(green, GPIO.OUT) + gpio.setup(blue, GPIO.OUT) + self._gpio.output_pins(self._rgb_to_pins(initial_color)) + + def _rgb_to_duty_cycle(self, rgb): + # Convert tuple of RGB 0-1 values to tuple of duty cycles (0-100). + red, green, blue = rgb + # Clamp colors between 0.0 and 1.0 + red = max(0.0, min(1.0, red)) + green = max(0.0, min(1.0, green)) + blue = max(0.0, min(1.0, blue)) + return (self._pwm_duty_cycle(red), + self._pwm_duty_cycle(green), + self._pwm_duty_cycle(blue)) + + def _rgb_to_pins(self, rgb): + # Convert tuple of RGB 0-1 values to dict of pin values. + red, green, blue = rgb + return { self._red: self._blpol if red else not self._blpol, + self._green: self._blpol if green else not self._blpol, + self._blue: self._blpol if blue else not self._blpol } + + def set_color(self, red, green, blue): + """Set backlight color to provided red, green, and blue values. If PWM + is enabled then color components can be values from 0.0 to 1.0, otherwise + components should be zero for off and non-zero for on. + """ + if self._pwm_enabled: + # Set duty cycle of PWM pins. + rdc, gdc, bdc = self._rgb_to_duty_cycle((red, green, blue)) + self._pwm.set_duty_cycle(self._red, rdc) + self._pwm.set_duty_cycle(self._green, gdc) + self._pwm.set_duty_cycle(self._blue, bdc) + else: + # Set appropriate backlight pins based on polarity and enabled colors. + self._gpio.output_pins({self._red: self._blpol if red else not self._blpol, + self._green: self._blpol if green else not self._blpol, + self._blue: self._blpol if blue else not self._blpol }) + + def set_backlight(self, backlight): + """Enable or disable the backlight. If PWM is not enabled (default), a + non-zero backlight value will turn on the backlight and a zero value will + turn it off. If PWM is enabled, backlight can be any value from 0.0 to + 1.0, with 1.0 being full intensity backlight. On an RGB display this + function will set the backlight to all white. + """ + self.set_color(backlight, backlight, backlight) + + + +class Adafruit_CharLCDPlate(Adafruit_RGBCharLCD): + """Class to represent and interact with an Adafruit Raspberry Pi character + LCD plate.""" + + def __init__(self, address=0x20, busnum=I2C.get_default_bus(), cols=16, lines=2): + """Initialize the character LCD plate. Can optionally specify a separate + I2C address or bus number, but the defaults should suffice for most needs. + Can also optionally specify the number of columns and lines on the LCD + (default is 16x2). + """ + # Configure MCP23017 device. + self._mcp = MCP.MCP23017(address=address, busnum=busnum) + # Set LCD R/W pin to low for writing only. + self._mcp.setup(LCD_PLATE_RW, GPIO.OUT) + self._mcp.output(LCD_PLATE_RW, GPIO.LOW) + # Set buttons as inputs with pull-ups enabled. + for button in (SELECT, RIGHT, DOWN, UP, LEFT): + self._mcp.setup(button, GPIO.IN) + self._mcp.pullup(button, True) + # Initialize LCD (with no PWM support). + super(Adafruit_CharLCDPlate, self).__init__(LCD_PLATE_RS, LCD_PLATE_EN, + LCD_PLATE_D4, LCD_PLATE_D5, LCD_PLATE_D6, LCD_PLATE_D7, cols, lines, + LCD_PLATE_RED, LCD_PLATE_GREEN, LCD_PLATE_BLUE, enable_pwm=False, + gpio=self._mcp) + + def is_pressed(self, button): + """Return True if the provided button is pressed, False otherwise.""" + if button not in set((SELECT, RIGHT, DOWN, UP, LEFT)): + raise ValueError('Unknown button, must be SELECT, RIGHT, DOWN, UP, or LEFT.') + return self._mcp.input(button) == GPIO.LOW + + +class Adafruit_CharLCDBackpack(Adafruit_CharLCD): + """Class to represent and interact with an Adafruit I2C / SPI + LCD backpack using I2C.""" + + def __init__(self, address=0x20, busnum=I2C.get_default_bus(), cols=16, lines=2): + """Initialize the character LCD plate. Can optionally specify a separate + I2C address or bus number, but the defaults should suffice for most needs. + Can also optionally specify the number of columns and lines on the LCD + (default is 16x2). + """ + # Configure the MCP23008 device. + self._mcp = MCP.MCP23008(address=address, busnum=busnum) + # Initialize LCD (with no PWM support). + super(Adafruit_CharLCDBackpack, self).__init__(LCD_BACKPACK_RS, LCD_BACKPACK_EN, + LCD_BACKPACK_D4, LCD_BACKPACK_D5, LCD_BACKPACK_D6, LCD_BACKPACK_D7, + cols, lines, LCD_BACKPACK_LITE, enable_pwm=False, gpio=self._mcp)
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