010 - ESP32 MicroPython: 0.96 OLED in MicroPython

  1#MicroPython SSD1306 OLED driver, I2C and SPI interfaces created by Adafruit
  2
  3import time
  4import framebuf
  5
  6# register definitions
  7SET_CONTRAST        = const(0x81)
  8SET_ENTIRE_ON       = const(0xa4)
  9SET_NORM_INV        = const(0xa6)
 10SET_DISP            = const(0xae)
 11SET_MEM_ADDR        = const(0x20)
 12SET_COL_ADDR        = const(0x21)
 13SET_PAGE_ADDR       = const(0x22)
 14SET_DISP_START_LINE = const(0x40)
 15SET_SEG_REMAP       = const(0xa0)
 16SET_MUX_RATIO       = const(0xa8)
 17SET_COM_OUT_DIR     = const(0xc0)
 18SET_DISP_OFFSET     = const(0xd3)
 19SET_COM_PIN_CFG     = const(0xda)
 20SET_DISP_CLK_DIV    = const(0xd5)
 21SET_PRECHARGE       = const(0xd9)
 22SET_VCOM_DESEL      = const(0xdb)
 23SET_CHARGE_PUMP     = const(0x8d)
 24
 25class SSD1306:
 26    def __init__(self, width, height, external_vcc):
 27        self.width = width
 28        self.height = height
 29        self.external_vcc = external_vcc
 30        self.pages = self.height // 8
 31        # Note the subclass must initialize self.framebuf to a framebuffer.
 32        # This is necessary because the underlying data buffer is different
 33        # between I2C and SPI implementations (I2C needs an extra byte).
 34        self.poweron()
 35        self.init_display()
 36
 37    def init_display(self):
 38        for cmd in (
 39            SET_DISP | 0x00, # off
 40            # address setting
 41            SET_MEM_ADDR, 0x00, # horizontal
 42            # resolution and layout
 43            SET_DISP_START_LINE | 0x00,
 44            SET_SEG_REMAP | 0x01, # column addr 127 mapped to SEG0
 45            SET_MUX_RATIO, self.height - 1,
 46            SET_COM_OUT_DIR | 0x08, # scan from COM[N] to COM0
 47            SET_DISP_OFFSET, 0x00,
 48            SET_COM_PIN_CFG, 0x02 if self.height == 32 else 0x12,
 49            # timing and driving scheme
 50            SET_DISP_CLK_DIV, 0x80,
 51            SET_PRECHARGE, 0x22 if self.external_vcc else 0xf1,
 52            SET_VCOM_DESEL, 0x30, # 0.83*Vcc
 53            # display
 54            SET_CONTRAST, 0xff, # maximum
 55            SET_ENTIRE_ON, # output follows RAM contents
 56            SET_NORM_INV, # not inverted
 57            # charge pump
 58            SET_CHARGE_PUMP, 0x10 if self.external_vcc else 0x14,
 59            SET_DISP | 0x01): # on
 60            self.write_cmd(cmd)
 61        self.fill(0)
 62        self.show()
 63
 64    def poweroff(self):
 65        self.write_cmd(SET_DISP | 0x00)
 66
 67    def contrast(self, contrast):
 68        self.write_cmd(SET_CONTRAST)
 69        self.write_cmd(contrast)
 70
 71    def invert(self, invert):
 72        self.write_cmd(SET_NORM_INV | (invert & 1))
 73
 74    def show(self):
 75        x0 = 0
 76        x1 = self.width - 1
 77        if self.width == 64:
 78            # displays with width of 64 pixels are shifted by 32
 79            x0 += 32
 80            x1 += 32
 81        self.write_cmd(SET_COL_ADDR)
 82        self.write_cmd(x0)
 83        self.write_cmd(x1)
 84        self.write_cmd(SET_PAGE_ADDR)
 85        self.write_cmd(0)
 86        self.write_cmd(self.pages - 1)
 87        self.write_framebuf()
 88
 89    def fill(self, col):
 90        self.framebuf.fill(col)
 91
 92    def pixel(self, x, y, col):
 93        self.framebuf.pixel(x, y, col)
 94
 95    def scroll(self, dx, dy):
 96        self.framebuf.scroll(dx, dy)
 97
 98    def text(self, string, x, y, col=1):
 99        self.framebuf.text(string, x, y, col)
100    
101    # Missing from current files in github:
102    # https://github.com/adafruit/micropython-adafruit-ssd1306/blob/master/ssd1306.py
103    def hline(self, x, y, w, col):
104        self.framebuf.hline(x, y, w, col)
105    def vline(self, x, y, h, col):
106        self.framebuf.vline(x, y, h, col)
107    def line(self, x1, y1, x2, y2, col):
108        self.framebuf.line(x1, y1, x2, y2, col)
109    def rect(self, x, y, w, h, col):
110        self.framebuf.rect(x, y, w, h, col)
111    def fill_rect(self, x, y, w, h, col):
112        self.framebuf.fill_rect(x, y, w, h, col)
113    def blit(self, fbuf, x, y):
114        self.framebuf.blit(fbuf, x, y)
115
116class SSD1306_I2C(SSD1306):
117    def __init__(self, width, height, i2c, addr=0x3c, external_vcc=False):
118        self.i2c = i2c
119        self.addr = addr
120        self.temp = bytearray(2)
121        # Add an extra byte to the data buffer to hold an I2C data/command byte
122        # to use hardware-compatible I2C transactions.  A memoryview of the
123        # buffer is used to mask this byte from the framebuffer operations
124        # (without a major memory hit as memoryview doesn't copy to a separate
125        # buffer).
126        self.buffer = bytearray(((height // 8) * width) + 1)
127        self.buffer[0] = 0x40  # Set first byte of data buffer to Co=0, D/C=1
128        self.framebuf = framebuf.FrameBuffer1(memoryview(self.buffer)[1:], width, height)
129        super().__init__(width, height, external_vcc)
130
131    def write_cmd(self, cmd):
132        self.temp[0] = 0x80 # Co=1, D/C#=0
133        self.temp[1] = cmd
134        self.i2c.writeto(self.addr, self.temp)
135
136    def write_framebuf(self):
137        # Blast out the frame buffer using a single I2C transaction to support
138        # hardware I2C interfaces.
139        self.i2c.writeto(self.addr, self.buffer)
140
141    def poweron(self):
142        pass
143
144class SSD1306_SPI(SSD1306):
145    def __init__(self, width, height, spi, dc, res, cs, external_vcc=False):
146        self.rate = 10 * 1024 * 1024
147        dc.init(dc.OUT, value=0)
148        res.init(res.OUT, value=0)
149        cs.init(cs.OUT, value=1)
150        self.spi = spi
151        self.dc = dc
152        self.res = res
153        self.cs = cs
154        self.buffer = bytearray((height // 8) * width)
155        self.framebuf = framebuf.FrameBuffer1(self.buffer, width, height)
156        super().__init__(width, height, external_vcc)
157
158    def write_cmd(self, cmd):
159        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
160        self.cs.high()
161        self.dc.low()
162        self.cs.low()
163        self.spi.write(bytearray([cmd]))
164        self.cs.high()
165
166    def write_framebuf(self):
167        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
168        self.cs.high()
169        self.dc.high()
170        self.cs.low()
171        self.spi.write(self.buffer)
172        self.cs.high()
173
174    def poweron(self):
175        self.res.high()
176        time.sleep_ms(1)
177        self.res.low()
178        time.sleep_ms(10)
179        self.res.high()

 1# Simple demonstration of 0.96 OLED in MicroPython
 2# Author: George Bantique, TechToTinker
 3# Date:   September 30, 2020
 4import ssd1306
 5import machine
 6
 7scl = machine.Pin(22, machine.Pin.OUT, machine.Pin.PULL_UP)
 8sda = machine.Pin(21, machine.Pin.OUT, machine.Pin.PULL_UP)
 9i2c = machine.I2C(scl=scl, sda=sda, freq=400000)
10oled = ssd1306.SSD1306_I2C(128, 64, i2c, addr=0x3C)
11
12def print_text(msg, x, y, clr):
13    if clr:
14        oled.fill(0)
15    oled.text(msg, x, y)
16    oled.show()
17
18print_text('Hello', 10, 10, 0)
19print_text('Welcome', 20, 20, 0)
20print_text('TechToTinker', 20, 20, 1)