【Banana PI Leaf S3开发板试用体验】+OLED屏显示驱动

OLED屏有多种形式，在例程中提供了一种I2C接口的0.96寸单色屏程序。本人则有一款I2C接口的0.96寸双色屏，在掌握GPIO口使用的基础上，以模拟I2C的方式实现了它的驱动显示。

其引脚的连接关系如下：

VCC----3.3V

GND---GND

SDA---- GPIO15

SCL---- GPIO16

图1 引脚连接

将所用引脚设置为输出模式的语句为：

sda=Pin(15,Pin.OUT) #15

sck=Pin(16,Pin.OUT) #16

实现数据数据发送的函数为：

def Write_IIC_Byte(IIC_Byte):
  da=IIC_Byte
  sck.off()
  for i in range(8):
     m=da
     m=m&0x80
     if(m==0x80):
       sda.on()
     else:
       sda.off()
     da=da<<1
     sck.on()
     sck.off()

实现清屏的函数为：

def OLED_Clear():
   for i in range(8):
     OLED_WR_Byte (0xb0+i,OLED_CMD)
     OLED_WR_Byte (0x00,OLED_CMD)
     OLED_WR_Byte (0x10,OLED_CMD)
   for j in range(128):
     OLED_WR_Byte(0x00,OLED_DATA)

OLED屏的初始化函数为：

def OLED_Init():
  OLED_WR_Byte(0xAE,OLED_CMD)
  OLED_WR_Byte(0x02,OLED_CMD)
  OLED_WR_Byte(0x10,OLED_CMD)
  OLED_WR_Byte(0x40,OLED_CMD)
  OLED_WR_Byte(0x81,OLED_CMD)
  OLED_WR_Byte(0xff,OLED_CMD)
  OLED_WR_Byte(0xA1,OLED_CMD)
  OLED_WR_Byte(0xC8,OLED_CMD)
  OLED_WR_Byte(0xA6,OLED_CMD)
  OLED_WR_Byte(0xA8,OLED_CMD)
  OLED_WR_Byte(0x3f,OLED_CMD)
  OLED_WR_Byte(0xD3,OLED_CMD)
  OLED_WR_Byte(0x00,OLED_CMD)
  OLED_WR_Byte(0xd5,OLED_CMD)
  OLED_WR_Byte(0x80,OLED_CMD)
  OLED_WR_Byte(0xD9,OLED_CMD)
  OLED_WR_Byte(0xF1,OLED_CMD)
  OLED_WR_Byte(0xDA,OLED_CMD)
  OLED_WR_Byte(0x12,OLED_CMD)
  OLED_WR_Byte(0xDB,OLED_CMD)
  OLED_WR_Byte(0x40,OLED_CMD)
  OLED_WR_Byte(0x20,OLED_CMD)
  OLED_WR_Byte(0x02,OLED_CMD)
  OLED_WR_Byte(0x8D,OLED_CMD)
  OLED_WR_Byte(0x14,OLED_CMD)
  OLED_WR_Byte(0xA4,OLED_CMD)
  OLED_WR_Byte(0xA6,OLED_CMD)
  OLED_WR_Byte(0xAF,OLED_CMD)
  OLED_WR_Byte(0xAF,OLED_CMD)
  OLED_Clear()
  OLED_Set_Pos(0,0)

为了验证程序的可行性，特将清屏函数改造为彩条绘制函数，其内容为：

def OLED_Clear():
   for i in range(8):
     OLED_WR_Byte (0xb0+i,OLED_CMD)
     OLED_WR_Byte (0x00,OLED_CMD)
     OLED_WR_Byte (0x10,OLED_CMD)
   for j in range(128):
     OLED_WR_Byte(0xf0,OLED_DATA) #OLED_DATA

def OLED_text():
   OLED_Init()
   OLED_Clear()

OLED_text ()

经上传测试，其显示效果如图2所示，说明驱动程序是有效的。

图2 绘制彩条

为了实现字符，需按如下形式来定义字库：

F8X16=[0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,

0x00,0x00,0x00,0xF8,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x33,0x30,0x00,0x00,0x00,

0x00,0x10,0x0C,0x06,0x10,0x0C,0x06,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,

** ... **

0x00,0x06,0x01,0x01,0x02,0x02,0x04,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00]

所设计的字符串显示函数为：

def OLED_ShowString(x,y,chr,Char_Size):
     for character in chr:
        OLED_ShowChar(x,y,character,Char_Size)
        x+=8
        if(x>120):
            x=0
            y+=2

实现字符串输出测试的程序如下：

def OLED_text():
   OLED_Init()
   OLED_Clear()
   OLED_ShowString(0,0,'Banana PI ',16)
   OLED_ShowString(0,2,'Leaf S3',16)
   OLED_ShowString(0,4,'OLED TEST',16)
   OLED_ShowString(0,6,'jinglixixi',16)

OLED_text()