feature/driver/sh1107: oled driver & 1 bit image file

Author: pandiannano

m5stack/fs/user/res/img/m5stack.pbm

@@ -0,0 +1,167 @@
+# https://www.displayfuture.com/Display/datasheet/controller/SH1107.pdf
+
+from micropython import const
+from framebuf import FrameBuffer, MONO_VLSB, MONO_HMSB, MONO_HLSB
+
+SET_CONTRAST = const(0x81)
+SET_ENTIRE_ON = const(0xA4)
+SET_NORM_INV = const(0xA6)
+SET_DISP = const(0xAE)
+SET_DCDC_MODE = const(0xAD)
+SET_MEM_MODE = const(0x20)
+SET_PAGE_ADDR = const(0xB0)
+SET_COL_LO_ADDR = const(0x00)
+SET_COL_HI_ADDR = const(0x10)
+SET_DISP_START_LINE = const(0xDC)
+SET_SEG_REMAP = const(0xA0)
+SET_MUX_RATIO = const(0xA8)
+SET_COM_OUT_DIR = const(0xC0)
+SET_DISP_OFFSET = const(0xD3)
+SET_DISP_CLK_DIV = const(0xD5)
+SET_PRECHARGE = const(0xD9)
+SET_VCOM_DESEL = const(0xDB)
+
+TEST_CHUNK = const(8)
+
+
+class SH1107(FrameBuffer):
+    def __init__(self, width, height, external_vcc):
+        self.external_vcc = external_vcc
+        if width == 128 and height == 64:
+            self.page_mode = False
+        elif (width == 64 and height == 128) or (width == 128 and height == 128):
+            self.page_mode = True
+        else:
+            raise ValueError
+        self.width = width
+        self.height = height
+        self.pages = self.height // 8
+        self.line_bytes = self.width // 8
+        size = self.width * self.height // 8
+        self.curr_buffer = bytearray(b'\x00' * size)  # self.fill(0)
+        self.prev_buffer = bytearray(b'\xff' * size)  # force full refresh
+        super().__init__(self.curr_buffer, self.width, self.height,
+                         MONO_VLSB if self.page_mode else MONO_HMSB)
+        self.init_display()
+        self.fill(0)
+        self.show()
+        try:
+            self.image(27, 0, "/flash/img/m5stack.pbm")
+            self.show()
+        except:
+            pass
+
+    def init_display(self):
+        for cmd in (
+            SET_DISP | 0x00,  # off
+            # address setting
+            # 0x00 = page, 0x01 = vertical
+            SET_MEM_MODE | (0x00 if self.page_mode else 0x01),
+            # resolution and layout
+            SET_DISP_START_LINE, 0x00,
+            SET_SEG_REMAP | 0x00,  # 0x01 rotate 180 deg
+            # 0x08 rotate 180 deg
+            SET_COM_OUT_DIR | (0x00 if self.page_mode else 0x08),
+            SET_MUX_RATIO, 0x7f,  # always this?
+            # offseted for 64 x 128 (Aliexpress 0.96")
+            SET_DISP_OFFSET, 0x60 if self.width != self.height else 0x00,
+            # timing and driving scheme
+            SET_DISP_CLK_DIV, 0x50,
+            SET_PRECHARGE, 0x22 if self.external_vcc else 0xf1,
+            SET_VCOM_DESEL, 0x35,  # 0.77 * Vcc
+            SET_DCDC_MODE, 0x81,  # on, 0.6 * switch freq
+            # display
+            SET_CONTRAST, 0x80,  # very low to avoid uneven background
+            SET_ENTIRE_ON | 0x00,  # output follows RAM contents, not entire on
+            SET_NORM_INV | 0x00  # 0x00 = not inverted, 0x01 = inverted
+        ):
+            self.write_cmd(cmd)
+        # buffers are initialized as if self.fill(0) was called
+        self.show()
+        self.poweron()
+
+    def poweroff(self):
+        self.write_cmd(SET_DISP | 0x00)
+
+    def poweron(self):
+        self.write_cmd(SET_DISP | 0x01)
+
+    def contrast(self, contrast):
+        self.write_cmd(SET_CONTRAST)
+        self.write_cmd(contrast)
+
+    def invert(self, invert):
+        self.write_cmd(SET_NORM_INV | (invert & 1))
+
+    def image(self, x, y, filename):
+        with open(filename, 'rb') as f:
+            f.readline()
+            f.readline()
+            width, height = [int(v) for v in f.readline().split()]
+            data = bytearray(f.read())
+        image = FrameBuffer(data, width, height, MONO_HLSB)
+        self.blit(image, x, y)
+
+    def show(self):
+        if self.page_mode:
+            self.show_page_mode()
+        else:
+            self.show_vert_mode()
+        self.prev_buffer[:] = self.curr_buffer
+
+    def show_page_mode(self):
+        for page in range(self.pages):
+            noffs = page * self.width
+            for col1, col2 in self.test_modified(noffs, self.width):
+                c = col1 - noffs
+                self.write_cmd(SET_PAGE_ADDR | page)
+                self.write_cmd(SET_COL_LO_ADDR | (c & 0x0f))
+                self.write_cmd(SET_COL_HI_ADDR | ((c & 0x70) >> 4))
+                self.write_data(self.curr_buffer[col1: col2])
+                # print('Write offsets {} : {}, col: {}'.format(col1, col2, c))
+
+    def show_vert_mode(self):
+        for col in range(self.height):
+            noffs = col * self.line_bytes
+            for page1, page2 in self.test_modified(noffs, self.line_bytes):
+                self.write_cmd(SET_PAGE_ADDR | (page1 - noffs))
+                self.write_cmd(SET_COL_LO_ADDR | (col & 0x0f))
+                self.write_cmd(SET_COL_HI_ADDR | ((col & 0x70) >> 4))
+                self.write_data(self.curr_buffer[page1: page2])
+                # print('Write offsets {} : {}, page: {}'.format(page1, page2, page1 - noffs))
+
+    def test_modified(self, offs, width):
+        ptr = offs
+        width += offs
+        while ptr < width:
+            # skip unmodified chunks
+            while ptr < width and self.curr_buffer[ptr: ptr + TEST_CHUNK] == self.prev_buffer[ptr: ptr + TEST_CHUNK]:
+                ptr += TEST_CHUNK
+
+            if ptr < width:
+                first = ptr
+                ptr += TEST_CHUNK
+                # find modified chunks
+                while ptr < width and self.curr_buffer[ptr:ptr + TEST_CHUNK] != self.prev_buffer[ptr:ptr + TEST_CHUNK]:
+                    ptr += TEST_CHUNK
+
+                yield first, ptr
+                ptr += TEST_CHUNK
+
+
+class SH1107_I2C(SH1107):
+    def __init__(self, width, height, i2c, addr=0x3C, external_vcc=False):
+        self.i2c = i2c
+        self.i2c_addr = addr
+        self.temp = bytearray(2)
+        self.write_list = [b'\x40', None]  # Co=0, D/C#=1
+        super().__init__(width, height, external_vcc)
+
+    def write_cmd(self, cmd):
+        self.temp[0] = 0x80  # Co=1, D/C#=0
+        self.temp[1] = cmd
+        self.i2c.writeto(self.i2c_addr, self.temp)
+
+    def write_data(self, buf):
+        self.write_list[1] = buf
+        self.i2c.writevto(self.i2c_addr, self.write_list)