# 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 numbers import time import numpy as np from PIL import Image from PIL import ImageDraw import Adafruit_GPIO as GPIO import Adafruit_GPIO.SPI as SPI # SPI_CLOCK_HZ = 64000000 # 64 MHz SPI_CLOCK_HZ = 4000000 # 4 MHz # Constants for interacting with display registers. ST7735_TFTWIDTH = 128 ST7735_TFTHEIGHT = 160 ST7735_NOP = 0x00 ST7735_SWRESET = 0x01 ST7735_RDDID = 0x04 ST7735_RDDST = 0x09 ST7735_SLPIN = 0x10 ST7735_SLPOUT = 0x11 ST7735_PTLON = 0x12 ST7735_NORON = 0x13 # ILI9341_RDMODE = 0x0A # ILI9341_RDMADCTL = 0x0B # ILI9341_RDPIXFMT = 0x0C # ILI9341_RDIMGFMT = 0x0A # ILI9341_RDSELFDIAG = 0x0F ST7735_INVOFF = 0x20 ST7735_INVON = 0x21 # ILI9341_GAMMASET = 0x26 ST7735_DISPOFF = 0x28 ST7735_DISPON = 0x29 ST7735_CASET = 0x2A ST7735_RASET = 0x2B ST7735_RAMWR = 0x2C ST7735_RAMRD = 0x2E ST7735_PTLAR = 0x30 ST7735_MADCTL = 0x36 # ST7735_PIXFMT = 0x3A ST7735_COLMOD = 0x3A ST7735_FRMCTR1 = 0xB1 ST7735_FRMCTR2 = 0xB2 ST7735_FRMCTR3 = 0xB3 ST7735_INVCTR = 0xB4 # ILI9341_DFUNCTR = 0xB6 ST7735_DISSET5 = 0xB6 ST7735_PWCTR1 = 0xC0 ST7735_PWCTR2 = 0xC1 ST7735_PWCTR3 = 0xC2 ST7735_PWCTR4 = 0xC3 ST7735_PWCTR5 = 0xC4 ST7735_VMCTR1 = 0xC5 # ILI9341_VMCTR2 = 0xC7 ST7735_RDID1 = 0xDA ST7735_RDID2 = 0xDB ST7735_RDID3 = 0xDC ST7735_RDID4 = 0xDD ST7735_GMCTRP1 = 0xE0 ST7735_GMCTRN1 = 0xE1 ST7735_PWCTR6 = 0xFC # Colours for convenience ST7735_BLACK = 0x0000 # 0b 00000 000000 00000 ST7735_BLUE = 0x001F # 0b 00000 000000 11111 ST7735_GREEN = 0x07E0 # 0b 00000 111111 00000 ST7735_RED = 0xF800 # 0b 11111 000000 00000 ST7735_CYAN = 0x07FF # 0b 00000 111111 11111 ST7735_MAGENTA = 0xF81F # 0b 11111 000000 11111 ST7735_YELLOW = 0xFFE0 # 0b 11111 111111 00000 ST7735_WHITE = 0xFFFF # 0b 11111 111111 11111 def color565(r, g, b): """Convert red, green, blue components to a 16-bit 565 RGB value. Components should be values 0 to 255. """ return ((r & 0xF8) << 8) | ((g & 0xFC) << 3) | (b >> 3) def image_to_data(image): """Generator function to convert a PIL image to 16-bit 565 RGB bytes.""" # NumPy is much faster at doing this. NumPy code provided by: # Keith (https://www.blogger.com/profile/02555547344016007163) pb = np.array(image.convert('RGB')).astype('uint16') # color = ((pb[:,:,0] & 0xF8) << 8) | ((pb[:,:,1] & 0xFC) << 3) | (pb[:,:,2] >> 3) color = ((pb[:,:,2] & 0xF8) << 8) | ((pb[:,:,1] & 0xFC) << 3) | (pb[:,:,0] >> 3) return np.dstack(((color >> 8) & 0xFF, color & 0xFF)).flatten().tolist() class ST7735(object): """Representation of an ST7735 TFT LCD.""" def __init__(self, dc, spi, rst=None, gpio=None, width=ST7735_TFTWIDTH, height=ST7735_TFTHEIGHT): """Create an instance of the display using SPI communication. Must provide the GPIO pin number for the D/C pin and the SPI driver. Can optionally provide the GPIO pin number for the reset pin as the rst parameter. """ self._dc = dc self._rst = rst self._spi = spi self._gpio = gpio self.width = width self.height = height if self._gpio is None: self._gpio = GPIO.get_platform_gpio() # Set DC as output. self._gpio.setup(dc, GPIO.OUT) # Setup reset as output (if provided). if rst is not None: self._gpio.setup(rst, GPIO.OUT) # Set SPI to mode 0, MSB first. spi.set_mode(0) spi.set_bit_order(SPI.MSBFIRST) spi.set_clock_hz(SPI_CLOCK_HZ) # Create an image buffer. self.buffer = Image.new('RGB', (width, height)) def send(self, data, is_data=True, chunk_size=4096): """Write a byte or array of bytes to the display. Is_data parameter controls if byte should be interpreted as display data (True) or command data (False). Chunk_size is an optional size of bytes to write in a single SPI transaction, with a default of 4096. """ # Set DC low for command, high for data. self._gpio.output(self._dc, is_data) # Convert scalar argument to list so either can be passed as parameter. if isinstance(data, numbers.Number): data = [data & 0xFF] # Write data a chunk at a time. for start in range(0, len(data), chunk_size): end = min(start+chunk_size, len(data)) self._spi.write(data[start:end]) def command(self, data): """Write a byte or array of bytes to the display as command data.""" self.send(data, False) def data(self, data): """Write a byte or array of bytes to the display as display data.""" self.send(data, True) def reset(self): """Reset the display, if reset pin is connected.""" if self._rst is not None: self._gpio.set_high(self._rst) time.sleep(0.500) self._gpio.set_low(self._rst) time.sleep(0.500) self._gpio.set_high(self._rst) time.sleep(0.500) def _init(self): # Initialize the display. Broken out as a separate function so it can # be overridden by other displays in the future. self.command(ST7735_SWRESET) # Software reset time.sleep(0.150) # delay 150 ms self.command(ST7735_SLPOUT) # Out of sleep mode time.sleep(0.500) # delay 500 ms self.command(ST7735_FRMCTR1) # Frame rate ctrl - normal mode self.data(0x01) # Rate = fosc/(1x2+40) * (LINE+2C+2D) self.data(0x2C) self.data(0x2D) self.command(ST7735_FRMCTR2) # Frame rate ctrl - idle mode self.data(0x01) # Rate = fosc/(1x2+40) * (LINE+2C+2D) self.data(0x2C) self.data(0x2D) self.command(ST7735_FRMCTR3) # Frame rate ctrl - partial mode self.data(0x01) # Dot inversion mode self.data(0x2C) self.data(0x2D) self.data(0x01) # Line inversion mode self.data(0x2C) self.data(0x2D) self.command(ST7735_INVCTR) # Display inversion ctrl self.data(0x07) # No inversion self.command(ST7735_PWCTR1) # Power control self.data(0xA2) self.data(0x02) # -4.6V self.data(0x84) # auto mode self.command(ST7735_PWCTR2) # Power control self.data(0x0A) # Opamp current small self.data(0x00) # Boost frequency self.command(ST7735_PWCTR4) # Power control self.data(0x8A) # BCLK/2, Opamp current small & Medium low self.data(0x2A) self.command(ST7735_PWCTR5) # Power control self.data(0x8A) self.data(0xEE) self.command(ST7735_VMCTR1) # Power control self.data(0x0E) self.command(ST7735_INVOFF) # Don't invert display self.command(ST7735_MADCTL) # Memory access control (directions) self.data(0xC8) # row addr/col addr, bottom to top refresh self.command(ST7735_COLMOD) # set color mode self.data(0x05) # 16-bit color # self.command(ST7735_CASET) # Column addr set self.data(0x00) # XSTART = 0 self.data(0x00) self.data(0x00) # XEND = 127 self.data(0x7F) self.command(ST7735_RASET) # Row addr set self.data(0x00) # XSTART = 0 self.data(0x00) self.data(0x00) # XEND = 159 self.data(0x9F) # self.command(ST7735_GMCTRP1) # Set Gamma self.data(0x02) self.data(0x1c) self.data(0x07) self.data(0x12) self.data(0x37) self.data(0x32) self.data(0x29) self.data(0x2d) self.data(0x29) self.data(0x25) self.data(0x2B) self.data(0x39) self.data(0x00) self.data(0x01) self.data(0x03) self.data(0x10) self.command(ST7735_GMCTRN1) # Set Gamma self.data(0x03) self.data(0x1d) self.data(0x07) self.data(0x06) self.data(0x2E) self.data(0x2C) self.data(0x29) self.data(0x2D) self.data(0x2E) self.data(0x2E) self.data(0x37) self.data(0x3F) self.data(0x00) self.data(0x00) self.data(0x02) self.data(0x10) self.command(ST7735_NORON) # Normal display on time.sleep(0.10) # 10 ms self.command(ST7735_DISPON) # Display on time.sleep(0.100) # 100 ms def begin(self): """Initialize the display. Should be called once before other calls that interact with the display are called. """ self.reset() self._init() def set_window(self, x0=0, y0=0, x1=None, y1=None): """Set the pixel address window for proceeding drawing commands. x0 and x1 should define the minimum and maximum x pixel bounds. y0 and y1 should define the minimum and maximum y pixel bound. If no parameters are specified the default will be to update the entire display from 0,0 to width-1,height-1. """ if x1 is None: x1 = self.width-1 if y1 is None: y1 = self.height-1 self.command(ST7735_CASET) # Column addr set self.data(x0 >> 8) self.data(x0) # XSTART self.data(x1 >> 8) self.data(x1) # XEND self.command(ST7735_RASET) # Row addr set self.data(y0 >> 8) self.data(y0) # YSTART self.data(y1 >> 8) self.data(y1) # YEND self.command(ST7735_RAMWR) # write to RAM def display(self, image=None): """Write the display buffer or provided image to the hardware. If no image parameter is provided the display buffer will be written to the hardware. If an image is provided, it should be RGB format and the same dimensions as the display hardware. """ # By default write the internal buffer to the display. if image is None: image = self.buffer # Set address bounds to entire display. self.set_window() # Convert image to array of 16bit 565 RGB data bytes. # Unfortunate that this copy has to occur, but the SPI byte writing # function needs to take an array of bytes and PIL doesn't natively # store images in 16-bit 565 RGB format. pixelbytes = list(image_to_data(image)) # Write data to hardware. self.data(pixelbytes) def clear(self, color=(0,0,0)): """Clear the image buffer to the specified RGB color (default black).""" width, height = self.buffer.size self.buffer.putdata([color]*(width*height)) def draw(self): """Return a PIL ImageDraw instance for 2D drawing on the image buffer.""" return ImageDraw.Draw(self.buffer)