【得捷电子Follow me第3期】任务2：驱动扩展板上的OLED屏幕（字符、表情、图形、动态

SeasonMay · 发表于2023-11-14 21:15

【得捷电子Follow me第3期】任务2：驱动扩展板上的OLED屏幕（字符、表情、图形、动态 [复制链接]

seeed xiao micropython官方文档链接：

https://wiki.seeedstudio.com/XIAO_ESP32C3_MicroPython/

在做显示任务的时候，一开始我按照官方文档打算直接在Thonny里配置并使用SSD1306

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但是搜索到SSD1306的库后安装时，一直报错如下：

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尝试了降低Thonny或者MicroPython的版本后，也还是不行，于是我就直接去复制了一份SSD1306的库文件直接放到ESP32的设备上，不过很多方法还是欠缺，因此我加了几个要用到的：

SSD1306.py:

```python
#MicroPython SSD1306 OLED driver, I2C and SPI interfaces created by Adafruit

import time
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)

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 poweroff(self):
        self.write_cmd(SET_DISP | 0x00)

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 show(self):
        x0 = 0
        x1 = self.width - 1
        if self.width == 64:
            # displays with width of 64 pixels are shifted by 32
            x0 += 32
            x1 += 32
        self.write_cmd(SET_COL_ADDR)
        self.write_cmd(x0)
        self.write_cmd(x1)
        self.write_cmd(SET_PAGE_ADDR)
        self.write_cmd(0)
        self.write_cmd(self.pages - 1)
        self.write_framebuf()

def fill(self, col):
        self.framebuf.fill(col)

def pixel(self, x, y, col):
        self.framebuf.pixel(x, y, col)

def scroll(self, dx, dy):
        self.framebuf.scroll(dx, dy)

def text(self, string, x, y, col=1):
        self.framebuf.text(string, x, y, col)
    # 下面几个方法自加，非官方提供
    def rect(self,x,y,w,h,c):
        self.framebuf.rect(x, y, w, h, c)
        
    def fill_rect(self,x,y,w,h,c):
        self.framebuf.fill_rect(x, y, w, h, c)
        
    def hline(self,x,y,w,c):
        self.framebuf.hline(x,y,w,c)
        
    def vline(self,x,y,h,c):
        self.framebuf.hline(x,y,h,c)
    
    def line(self,x1,y1,x2,y2,c):
        self.framebuf.line(x1,y1,x2,y2,c)
        
    def circle(self, center_x, center_y, radius, color):
        """Draw a circle at the given midpoint location, radius and color.
        The ```circle```method draws only a 1 pixel outline."""
        x = radius - 1
        y = 0
        d_x = 1
        d_y = 1
        err = d_x - (radius << 1)
        while x >= y:
            self.pixel(center_x + x, center_y + y, color)
            self.pixel(center_x + y, center_y + x, color)
            self.pixel(center_x - y, center_y + x, color)
            self.pixel(center_x - x, center_y + y, color)
            self.pixel(center_x - x, center_y - y, color)
            self.pixel(center_x - y, center_y - x, color)
            self.pixel(center_x + y, center_y - x, color)
            self.pixel(center_x + x, center_y - y, color)
            if err <= 0:
                y += 1
                err += d_y
                d_y += 2
            if err > 0:
                x -= 1
                d_x += 2
                err += d_x - (radius << 1)

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_cmd(self, cmd):
        self.temp[0] = 0x80 # Co=1, D/C#=0
        self.temp[1] = cmd
        self.i2c.writeto(self.addr, self.temp)

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)

def poweron(self):
        pass

class SSD1306_SPI(SSD1306):
    def __init__(self, width, height, spi, dc, res, cs, external_vcc=False):
        self.rate = 10 * 1024 * 1024
        dc.init(dc.OUT, value=0)
        res.init(res.OUT, value=0)
        cs.init(cs.OUT, value=1)
        self.spi = spi
        self.dc = dc
        self.res = res
        self.cs = cs
        self.buffer = bytearray((height // 8) * width)
        self.framebuf = framebuf.FrameBuffer1(self.buffer, width, height)
        super().__init__(width, height, external_vcc)

def write_cmd(self, cmd):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        self.cs.high()
        self.dc.low()
        self.cs.low()
        self.spi.write(bytearray([cmd]))
        self.cs.high()

def write_framebuf(self):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        self.cs.high()
        self.dc.high()
        self.cs.low()
        self.spi.write(self.buffer)
        self.cs.high()

def poweron(self):
        self.res.high()
        time.sleep_ms(1)
        self.res.low()
        time.sleep_ms(10)
        self.res.high()
```

然后新开一个py文件，测试一下：

```python
import time
from machine import Pin, SoftI2C
import ssd1306
import math

# Pin assignment
i2c = SoftI2C(scl=Pin(7), sda=Pin(6))  
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

oled.fill(0)  # Clear the screen
oled.text("Hello, ESP32-C3", 10, 15)
oled.text("/////", 30, 40)
oled.text("(`3`)y", 30, 55)
oled.show()  # Show the text
```

点击运行，效果如下：

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显示图形，比如画个简单的小圆圈：

```python
import time
from machine import Pin, SoftI2C
import ssd1306
import math

# Pin assignment
i2c = SoftI2C(scl=Pin(7), sda=Pin(6))  # Adjust the Pin numbers based on your connections
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

center_x = oled_width // 2
center_y = oled_height // 2

oled.fill(0)  # Clear the screen
oled.circle(center_x,center_y,30,1)
oled.show()  # Show the text
```

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在此基础上，再看看动态显示效果，修改下官方例程：

```python
import time
from machine import Pin, SoftI2C
import ssd1306
import math

# Pin assignment
i2c = SoftI2C(scl=Pin(7), sda=Pin(6))  # Adjust the Pin numbers based on your connections
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

center_x = oled_width // 2
center_y = oled_height // 2
square_size = 6  # Size of each square
num_squares = 12  # Number of squares
angle_increment = 2 * math.pi / num_squares

while True:
    oled.fill(0)  # Clear the screen
    oled.circle(center_x+2,center_y+2,20,1)
    for i in range(num_squares):
        angle = i * angle_increment
        x = int(center_x + (center_x - square_size-30) * math.cos(angle))
        y = int(center_y + (center_x - square_size-30) * math.sin(angle))
        
        # Draw all squares
        for j in range(num_squares):
            angle_j = j * angle_increment
            x_j = int(center_x + (center_x - square_size-30) * math.cos(angle_j))
            y_j = int(center_y + (center_x - square_size-30) * math.sin(angle_j))
            
            oled.fill_rect(x_j, y_j, square_size, square_size, 1)  # Draw the square
        
        oled.fill_rect(x, y, square_size, square_size, 0)  # Erase the current square
        oled.show()
        time.sleep_ms(100)  # Pause before next iteration
```

chejm · 发表于2023-11-18 21:25

楼主辛苦了，感谢楼主提供的这么好技术分享，顶起来

【得捷电子Follow me第3期】任务2：驱动扩展板上的OLED屏幕（字符、表情、图形、动态 [复制链接]

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