# (c) Copyright 2018 by Coinkite Inc. This file is covered by license found in COPYING-CC. # # ssd1306.py - MicroPython SSD1306 OLED driver, with SPI interface # # Copied from ../external/micropython/drivers/display/ssd1306.py # import time from micropython import const import framebuf # register definitions SET_CONTRAST = const(0x81) SET_ENTIRE_ON = const(0xa4) SET_NORM_INV = const(0xa6) SET_DISP = const(0xae) SET_MEM_ADDR = const(0x20) SET_COL_ADDR = const(0x21) SET_PAGE_ADDR = const(0x22) SET_DISP_START_LINE = const(0x40) SET_SEG_REMAP = const(0xa0) SET_MUX_RATIO = const(0xa8) SET_COM_OUT_DIR = const(0xc0) SET_DISP_OFFSET = const(0xd3) SET_COM_PIN_CFG = const(0xda) SET_DISP_CLK_DIV = const(0xd5) SET_PRECHARGE = const(0xd9) SET_VCOM_DESEL = const(0xdb) SET_CHARGE_PUMP = const(0x8d) # Subclassing FrameBuffer provides support for graphics primitives # see # class SSD1306(framebuf.FrameBuffer): def __init__(self, width, height, is_mk5): self.width = width self.height = height self.is_mk5 = is_mk5 self.pages = self.height // 8 self.buffer = bytearray(1024) #assert len(self.buffer) == self.pages * self.width super().__init__(self.buffer, self.width, self.height, framebuf.MONO_VLSB) self.init_display() def init_display(self): if not self.is_mk5: # Mk4 and earlier cmds = ( SET_DISP | 0x00, # display 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, 0x12, # timing and driving scheme SET_DISP_CLK_DIV, 0xF0, SET_PRECHARGE, 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, 0x14) else: # Mk5 has external +12v power supply, and different setup protocol cmds = ( SET_DISP | 0x00, # display off # address setting SET_MEM_ADDR, 0x00, # horizontal # resolution and layout SET_DISP_START_LINE | 0x00, SET_SEG_REMAP | 0x00, # column addr 0 mapped to SEG127 SET_MUX_RATIO, self.height - 1, SET_COM_OUT_DIR | 0x00, # scan from COM[8] to COM[N] SET_DISP_OFFSET, 0x00, SET_COM_PIN_CFG, 0x12, # timing and driving scheme SET_DISP_CLK_DIV, 0xF0, SET_PRECHARGE, 0x22, SET_VCOM_DESEL, 0x40, # per spec sheet # display SET_CONTRAST, 0x85, # NOT maximum, because spec sheet SET_ENTIRE_ON, # output follows RAM contents SET_NORM_INV, # not inverted SET_CHARGE_PUMP, 0x10, # charge pump: DISABLE ) self.write_cmds(cmds) self.fill(0) self.show() self.write_cmd(SET_DISP | 0x01) def write_cmds(self, cmds): for c in cmds: self.write_cmd(c) def poweroff(self): self.write_cmd(SET_DISP | 0x00) def poweron(self): self.write_cmd(SET_DISP | 0x01) def contrast(self, contrast): # brightness: normal = 0x7f, brightness=0xff, dim=0x00 (but they are all very similar) if self.is_mk5: # - limit to a specific max value from OLED specs used on Mk5 contrast = max(contrast, 0x85) self.write_cmd(SET_CONTRAST) self.write_cmd(contrast) def invert(self, invert): self.write_cmd(SET_NORM_INV | (invert & 1)) def show(self): self.write_cmd(SET_COL_ADDR) self.write_cmd(0) self.write_cmd(self.width - 1) self.write_cmd(SET_PAGE_ADDR) self.write_cmd(0) self.write_cmd(self.pages - 1) self.write_data(self.buffer) def busy_bar(self, enable, pattern): # Render a continuous activity (not progress) bar in lower 8 lines of display # - using OLED itself to do the animation, so smooth and CPU free # - cannot preserve bottom 8 lines, since we have to destructively write there # - assumes normal horz addr mode: 0x20, 0x00 # - speed_code=>framedelay: 0=5fr, 1=64fr, 2=128, 3=256, 4=3, 5=4, 6=25, 7=2frames # unused: assert 0 <= speed_code <= 7 setup = bytes([ 0x21, 0x00, 0x7f, # setup column address range (start, end): 0-127 0x22, 7, 7, # setup page start/end address: page 7=last 8 lines ]) if not self.is_mk5: animate = bytes([ 0x2e, # stop animations in progress 0x26, # scroll leftwards (stock ticker mode) 0, # placeholder 7, # start 'page' (vertical) 5, # "speed_code" # scroll speed: 7=fastest, but no order to it 7, # end 'page' 0, 0x7f, # start/end columns 0x2f # start ]) else: # SSD1309? doesn't implement 0x26 but has other commands animate = bytes([ 0x2e, # stop animations in progress 0x29, # Vert+Right horz animation setup 1, # A: enable horz scroll 7, # B: start 'page' (vertical) 5, # C: "speed_code" # scroll speed: 7=fastest, but no order to it 7, # D: end 'page' 1, # E: vert scrolling offset (unused) 0, 0x7f, # F,G: start/end columns 0xa3, # Set Vertical scroll Area 0, 0, # A, B: # of rows in fixed vs. scroll area 0x2f # start animating ]) cleanup = bytes([ 0x2e, # stop animation 0x20, 0x00, # horz addr-ing mode 0x21, 0x00, 0x7f, # setup column address range (start, end): 0-127 0x22, 7, 7, # setup page start/end address: page 7=last 8 lines ]) if not enable: # stop animation, and redraw old (new) screen self.write_cmds(cleanup) else: # needs a pattern that repeats nicely mod 128 self.write_cmds(setup) self.write_data(pattern) self.write_cmds(animate) class SSD1306_SPI(SSD1306): def __init__(self, width, height, spi, dc, res, cs, is_mk5=False): self.spi = spi self.dc = dc self.cs = cs self.res = res # initial states dc(0) cs(1) # reset sequence res(1) time.sleep_ms(1) res(0) time.sleep_ms(10) res(1) super().__init__(width, height, is_mk5) def _setup_spi(self): # need to re-do this constantly # max chip can do, still slower than display limit tho # - 40Mhz (target) is fine for short-cabled Mk4 (actual is lower?) # - max spec is 10Mhz on Mk5 rate = 40_000_000 if not self.is_mk5 else 10_000_000 self.spi.init(baudrate=rate, polarity=0, phase=0) def write_cmd(self, cmd): self._setup_spi() self.cs(1) self.dc(0) self.cs(0) self.spi.write(bytearray([cmd])) self.cs(1) def write_data(self, buf): self._setup_spi() self.cs(1) self.dc(1) self.cs(0) self.spi.write(buf) self.cs(1) # EOF