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| 1 | +# MicroPython SSD1306 OLED driver, I2C and SPI interfaces |
| 2 | + |
| 3 | +from micropython import const |
| 4 | +import framebuf |
| 5 | + |
| 6 | + |
| 7 | +# register definitions |
| 8 | +SET_CONTRAST = const(0x81) |
| 9 | +SET_ENTIRE_ON = const(0xA4) |
| 10 | +SET_NORM_INV = const(0xA6) |
| 11 | +SET_DISP = const(0xAE) |
| 12 | +SET_MEM_ADDR = const(0x20) |
| 13 | +SET_COL_ADDR = const(0x21) |
| 14 | +SET_PAGE_ADDR = const(0x22) |
| 15 | +SET_DISP_START_LINE = const(0x40) |
| 16 | +SET_SEG_REMAP = const(0xA0) |
| 17 | +SET_MUX_RATIO = const(0xA8) |
| 18 | +SET_IREF_SELECT = const(0xAD) |
| 19 | +SET_COM_OUT_DIR = const(0xC0) |
| 20 | +SET_DISP_OFFSET = const(0xD3) |
| 21 | +SET_COM_PIN_CFG = const(0xDA) |
| 22 | +SET_DISP_CLK_DIV = const(0xD5) |
| 23 | +SET_PRECHARGE = const(0xD9) |
| 24 | +SET_VCOM_DESEL = const(0xDB) |
| 25 | +SET_CHARGE_PUMP = const(0x8D) |
| 26 | + |
| 27 | +# Subclassing FrameBuffer provides support for graphics primitives |
| 28 | +# http://docs.micropython.org/en/latest/pyboard/library/framebuf.html |
| 29 | +class SSD1306(framebuf.FrameBuffer): |
| 30 | + def __init__(self, width, height, external_vcc): |
| 31 | + self.width = width |
| 32 | + self.height = height |
| 33 | + self.external_vcc = external_vcc |
| 34 | + self.pages = self.height // 8 |
| 35 | + self.buffer = bytearray(self.pages * self.width) |
| 36 | + super().__init__(self.buffer, self.width, self.height, framebuf.MONO_VLSB) |
| 37 | + self.init_display() |
| 38 | + |
| 39 | + def init_display(self): |
| 40 | + for cmd in ( |
| 41 | + SET_DISP, # display off |
| 42 | + # address setting |
| 43 | + SET_MEM_ADDR, |
| 44 | + 0x00, # horizontal |
| 45 | + # resolution and layout |
| 46 | + SET_DISP_START_LINE, # start at line 0 |
| 47 | + SET_SEG_REMAP | 0x01, # column addr 127 mapped to SEG0 |
| 48 | + SET_MUX_RATIO, |
| 49 | + self.height - 1, |
| 50 | + SET_COM_OUT_DIR | 0x08, # scan from COM[N] to COM0 |
| 51 | + SET_DISP_OFFSET, |
| 52 | + 0x00, |
| 53 | + SET_COM_PIN_CFG, |
| 54 | + 0x02 if self.width > 2 * self.height else 0x12, |
| 55 | + # timing and driving scheme |
| 56 | + SET_DISP_CLK_DIV, |
| 57 | + 0x80, |
| 58 | + SET_PRECHARGE, |
| 59 | + 0x22 if self.external_vcc else 0xF1, |
| 60 | + SET_VCOM_DESEL, |
| 61 | + 0x30, # 0.83*Vcc |
| 62 | + # display |
| 63 | + SET_CONTRAST, |
| 64 | + 0xFF, # maximum |
| 65 | + SET_ENTIRE_ON, # output follows RAM contents |
| 66 | + SET_NORM_INV, # not inverted |
| 67 | + SET_IREF_SELECT, |
| 68 | + 0x30, # enable internal IREF during display on |
| 69 | + # charge pump |
| 70 | + SET_CHARGE_PUMP, |
| 71 | + 0x10 if self.external_vcc else 0x14, |
| 72 | + SET_DISP | 0x01, # display on |
| 73 | + ): # on |
| 74 | + self.write_cmd(cmd) |
| 75 | + self.fill(0) |
| 76 | + self.show() |
| 77 | + |
| 78 | + def poweroff(self): |
| 79 | + self.write_cmd(SET_DISP) |
| 80 | + |
| 81 | + def poweron(self): |
| 82 | + self.write_cmd(SET_DISP | 0x01) |
| 83 | + |
| 84 | + def contrast(self, contrast): |
| 85 | + self.write_cmd(SET_CONTRAST) |
| 86 | + self.write_cmd(contrast) |
| 87 | + |
| 88 | + def invert(self, invert): |
| 89 | + self.write_cmd(SET_NORM_INV | (invert & 1)) |
| 90 | + |
| 91 | + def rotate(self, rotate): |
| 92 | + self.write_cmd(SET_COM_OUT_DIR | ((rotate & 1) << 3)) |
| 93 | + self.write_cmd(SET_SEG_REMAP | (rotate & 1)) |
| 94 | + |
| 95 | + def show(self): |
| 96 | + x0 = 0 |
| 97 | + x1 = self.width - 1 |
| 98 | + if self.width != 128: |
| 99 | + # narrow displays use centred columns |
| 100 | + col_offset = (128 - self.width) // 2 |
| 101 | + x0 += col_offset |
| 102 | + x1 += col_offset |
| 103 | + self.write_cmd(SET_COL_ADDR) |
| 104 | + self.write_cmd(x0) |
| 105 | + self.write_cmd(x1) |
| 106 | + self.write_cmd(SET_PAGE_ADDR) |
| 107 | + self.write_cmd(0) |
| 108 | + self.write_cmd(self.pages - 1) |
| 109 | + self.write_data(self.buffer) |
| 110 | + |
| 111 | + |
| 112 | +class SSD1306_I2C(SSD1306): |
| 113 | + def __init__(self, width, height, i2c, addr=0x3C, external_vcc=False): |
| 114 | + self.i2c = i2c |
| 115 | + self.addr = addr |
| 116 | + self.temp = bytearray(2) |
| 117 | + self.write_list = [b"\x40", None] # Co=0, D/C#=1 |
| 118 | + super().__init__(width, height, external_vcc) |
| 119 | + |
| 120 | + def write_cmd(self, cmd): |
| 121 | + self.temp[0] = 0x80 # Co=1, D/C#=0 |
| 122 | + self.temp[1] = cmd |
| 123 | + self.i2c.writeto(self.addr, self.temp) |
| 124 | + |
| 125 | + def write_data(self, buf): |
| 126 | + self.write_list[1] = buf |
| 127 | + self.i2c.writevto(self.addr, self.write_list) |
| 128 | + |
| 129 | + |
| 130 | +class SSD1306_SPI(SSD1306): |
| 131 | + def __init__(self, width, height, spi, dc, res, cs, external_vcc=False): |
| 132 | + self.rate = 10 * 1024 * 1024 |
| 133 | + dc.init(dc.OUT, value=0) |
| 134 | + res.init(res.OUT, value=0) |
| 135 | + cs.init(cs.OUT, value=1) |
| 136 | + self.spi = spi |
| 137 | + self.dc = dc |
| 138 | + self.res = res |
| 139 | + self.cs = cs |
| 140 | + import time |
| 141 | + |
| 142 | + self.res(1) |
| 143 | + time.sleep_ms(1) |
| 144 | + self.res(0) |
| 145 | + time.sleep_ms(10) |
| 146 | + self.res(1) |
| 147 | + super().__init__(width, height, external_vcc) |
| 148 | + |
| 149 | + def write_cmd(self, cmd): |
| 150 | + self.spi.init(baudrate=self.rate, polarity=0, phase=0) |
| 151 | + self.cs(1) |
| 152 | + self.dc(0) |
| 153 | + self.cs(0) |
| 154 | + self.spi.write(bytearray([cmd])) |
| 155 | + self.cs(1) |
| 156 | + |
| 157 | + def write_data(self, buf): |
| 158 | + self.spi.init(baudrate=self.rate, polarity=0, phase=0) |
| 159 | + self.cs(1) |
| 160 | + self.dc(1) |
| 161 | + self.cs(0) |
| 162 | + self.spi.write(buf) |
| 163 | + self.cs(1) |
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