class SSD1306:
def __init__(self, width, height, external_vcc):
self.width = width
self.height = height
self.external_vcc = external_vcc
self.pages = self.height // 8
# Note the subclass must initialize self.framebuf to a framebuffer.
# This is necessary because the underlying data buffer is different
# between I2C and SPI implementations (I2C needs an extra byte).
self.poweron()
self.init_display()
def init_display(self):
for cmd in (
SET_DISP | 0x00, # off
# address setting
SET_MEM_ADDR, 0x00, # horizontal
# resolution and layout
SET_DISP_START_LINE | 0x00,
SET_SEG_REMAP | 0x01, # column addr 127 mapped to SEG0
SET_MUX_RATIO, self.height - 1,
SET_COM_OUT_DIR | 0x08, # scan from COM[N] to COM0
SET_DISP_OFFSET, 0x00,
SET_COM_PIN_CFG, 0x02 if self.height == 32 else 0x12,
# timing and driving scheme
SET_DISP_CLK_DIV, 0x80,
SET_PRECHARGE, 0x22 if self.external_vcc else 0xf1,
SET_VCOM_DESEL, 0x30, # 0.83*Vcc
# display
SET_CONTRAST, 0xff, # maximum
SET_ENTIRE_ON, # output follows RAM contents
SET_NORM_INV, # not inverted
# charge pump
SET_CHARGE_PUMP, 0x10 if self.external_vcc else 0x14,
SET_DISP | 0x01): # on
self.write_cmd(cmd)
self.fill(0)
self.show()
def text(self, string, x, y, col=1):
self.framebuf.text(string, x, y, col)
class SSD1306_I2C(SSD1306):
def __init__(self, width, height, i2c, addr=0x3c, external_vcc=False):
self.i2c = i2c
self.addr = addr
self.temp = bytearray(2)
# Add an extra byte to the data buffer to hold an I2C data/command byte
# to use hardware-compatible I2C transactions. A memoryview of the
# buffer is used to mask this byte from the framebuffer operations
# (without a major memory hit as memoryview doesn't copy to a separate
# buffer).
self.buffer = bytearray(((height // 8) * width) + 1)
self.buffer[0] = 0x40 # Set first byte of data buffer to Co=0, D/C=1
self.framebuf = framebuf.FrameBuffer1(memoryview(self.buffer)[1:], width, height)
super().__init__(width, height, external_vcc)
def write_framebuf(self):
# Blast out the frame buffer using a single I2C transaction to support
# hardware I2C interfaces.
self.i2c.writeto(self.addr, self.buffer)
class SSD1306:
def __init__(self, width, height, external_vcc):
self.width = width
self.height = height
self.external_vcc = external_vcc
self.pages = self.height // 8
# Note the subclass must initialize self.framebuf to a framebuffer.
# This is necessary because the underlying data buffer is different
# between I2C and SPI implementations (I2C needs an extra byte).
self.poweron()
self.init_display()
def init_display(self):
for cmd in (
SET_DISP | 0x00, # off
# address setting
SET_MEM_ADDR, 0x00, # horizontal
# resolution and layout
SET_DISP_START_LINE | 0x00,
SET_SEG_REMAP | 0x01, # column addr 127 mapped to SEG0
SET_MUX_RATIO, self.height - 1,
SET_COM_OUT_DIR | 0x08, # scan from COM[N] to COM0
SET_DISP_OFFSET, 0x00,
SET_COM_PIN_CFG, 0x02 if self.height == 32 else 0x12,
# timing and driving scheme
SET_DISP_CLK_DIV, 0x80,
SET_PRECHARGE, 0x22 if self.external_vcc else 0xf1,
SET_VCOM_DESEL, 0x30, # 0.83*Vcc
# display
SET_CONTRAST, 0xff, # maximum
SET_ENTIRE_ON, # output follows RAM contents
SET_NORM_INV, # not inverted
# charge pump
SET_CHARGE_PUMP, 0x10 if self.external_vcc else 0x14,
SET_DISP | 0x01): # on
self.write_cmd(cmd)
self.fill(0)
self.show()
def text(self, string, x, y, col=1):
self.framebuf.text(string, x, y, col)
class SSD1306_I2C(SSD1306):
def __init__(self, width, height, i2c, addr=0x3c, external_vcc=False):
self.i2c = i2c
self.addr = addr
self.temp = bytearray(2)
# Add an extra byte to the data buffer to hold an I2C data/command byte
# to use hardware-compatible I2C transactions. A memoryview of the
# buffer is used to mask this byte from the framebuffer operations
# (without a major memory hit as memoryview doesn't copy to a separate
# buffer).
self.buffer = bytearray(((height // 8) * width) + 1)
self.buffer[0] = 0x40 # Set first byte of data buffer to Co=0, D/C=1
self.framebuf = framebuf.FrameBuffer1(memoryview(self.buffer)[1:], width, height)
super().__init__(width, height, external_vcc)
def write_framebuf(self):
# Blast out the frame buffer using a single I2C transaction to support
# hardware I2C interfaces.
self.i2c.writeto(self.addr, self.buffer)
Warning: I2C(-1, ...) is deprecated, use SoftI2C(...) instead
Traceback (most recent call last):
File "main.py", line 9, in <module>
File "ssd1306.py", line 116, in __init__
File "ssd1306.py", line 42, in __init__
File "ssd1306.py", line 66, in init_display
File "ssd1306.py", line 123, in write_cmd
OSError: [Errno 19] ENODEV