首先很感谢极术社区举办的这次开发板试用活动，正好公司项目涉及到一个链路管理装置，便先在GD32F427开发板上实现软件模拟IIC驱动OLED。
首先初始化对应GPIO：
void IIC_Init(void)
{
rcu_periph_clock_enable(RCU_GPIOB); //使能GPIOB组时钟
gpio_init(GPIOB, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_7); //配置PB7为推挽输出模式
gpio_init(GPIOB, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_6); //配置PB6为推挽输出模式
}模拟IIC时序
#include "oled.h"
#include "stdlib.h"
#include "oledfont.h"
#include "systick.h" //引入延时函数
//OLED的显存
//存放格式如下.
//[0]0 1 2 3 ... 127
//[1]0 1 2 3 ... 127
//[2]0 1 2 3 ... 127
//[3]0 1 2 3 ... 127
//[4]0 1 2 3 ... 127
//[5]0 1 2 3 ... 127
//[6]0 1 2 3 ... 127
//[7]0 1 2 3 ... 127
/**********************************************
//IIC Start
**********************************************/
/**********************************************
//IIC Start
**********************************************/
void IIC_Start()
{
OLED_SCLK_Set() ;
OLED_SDIN_Set();
OLED_SDIN_Clr();
OLED_SCLK_Clr();
}
/**********************************************
//IIC Stop
**********************************************/
void IIC_Stop()
{
OLED_SCLK_Set() ;
// OLED_SCLK_Clr();
OLED_SDIN_Clr();
OLED_SDIN_Set();
}
void IIC_Wait_Ack()
{
//GPIOB->CRH &= 0XFFF0FFFF; //设置PB12为上拉输入模式
//GPIOB->CRH |= 0x00080000;
// OLED_SDA = 1;
// delay_us(1);
//OLED_SCL = 1;
//delay_us(50000);
/* while(1)
{
if(!OLED_SDA) //判断是否接收到OLED 应答信号
{
//GPIOB->CRH &= 0XFFF0FFFF; //设置PB12为通用推免输出模式
//GPIOB->CRH |= 0x00030000;
return;
}
}
*/
OLED_SCLK_Set() ;
OLED_SCLK_Clr();
}
/**********************************************
// IIC Write byte
**********************************************/
void Write_IIC_Byte(unsigned char IIC_Byte)
{
unsigned char i;
unsigned char m, da;
da = IIC_Byte;
OLED_SCLK_Clr();
for(i = 0; i < 8; i++)
{
m = da;
// OLED_SCLK_Clr();
m = m & 0x80;
if(m == 0x80)
{
OLED_SDIN_Set();
}
else OLED_SDIN_Clr();
da = da << 1;
OLED_SCLK_Set();
OLED_SCLK_Clr();
}
}
/**********************************************
// IIC Write Command
**********************************************/
void Write_IIC_Command(unsigned char IIC_Command)
{
IIC_Start();
Write_IIC_Byte(0x78); //Slave address,SA0=0
IIC_Wait_Ack();
Write_IIC_Byte(0x00); //write command
IIC_Wait_Ack();
Write_IIC_Byte(IIC_Command);
IIC_Wait_Ack();
IIC_Stop();
}
/**********************************************
// IIC Write Data
**********************************************/
void Write_IIC_Data(unsigned char IIC_Data)
{
IIC_Start();
Write_IIC_Byte(0x78); //D/C#=0; R/W#=0
IIC_Wait_Ack();
Write_IIC_Byte(0x40); //write data
IIC_Wait_Ack();
Write_IIC_Byte(IIC_Data);
IIC_Wait_Ack();
IIC_Stop();
}
void OLED_WR_Byte(unsigned dat, unsigned cmd)
{
if(cmd)
{
Write_IIC_Data(dat);
}
else
{
Write_IIC_Command(dat);
}
}
/********************************************
// fill_Picture
********************************************/
void fill_picture(unsigned char fill_Data)
{
unsigned char m, n;
for(m = 0; m < 8; m++)
{
OLED_WR_Byte(0xb0 + m, 0); //page0-page1
OLED_WR_Byte(0x00, 0); //low column start address
OLED_WR_Byte(0x10, 0); //high column start address
for(n = 0; n < 128; n++)
{
OLED_WR_Byte(fill_Data, 1);
}
}
}
/***********************Delay****************************************/
void Delay_50ms(unsigned int Del_50ms)
{
unsigned int m;
for(; Del_50ms > 0; Del_50ms--)
for(m = 6245; m > 0; m--);
}
void Delay_1ms(unsigned int Del_1ms)
{
unsigned char j;
while(Del_1ms--)
{
for(j = 0; j < 123; j++);
}
}
//坐标设置
void OLED_Set_Pos(unsigned char x, unsigned char y)
{
OLED_WR_Byte(0xb0 + y, OLED_CMD);
OLED_WR_Byte(((x & 0xf0) >> 4) | 0x10, OLED_CMD);
OLED_WR_Byte((x & 0x0f), OLED_CMD);
}
//开启OLED显示
void OLED_Display_On(void)
{
OLED_WR_Byte(0X8D, OLED_CMD); //SET DCDC命令
OLED_WR_Byte(0X14, OLED_CMD); //DCDC ON
OLED_WR_Byte(0XAF, OLED_CMD); //DISPLAY ON
}
//关闭OLED显示
void OLED_Display_Off(void)
{
OLED_WR_Byte(0X8D, OLED_CMD); //SET DCDC命令
OLED_WR_Byte(0X10, OLED_CMD); //DCDC OFF
OLED_WR_Byte(0XAE, OLED_CMD); //DISPLAY OFF
}
//清屏函数,清完屏,整个屏幕是黑色的!和没点亮一样!!!
void OLED_Clear(void)
{
u8 i, n;
for(i = 0; i < 8; i++)
{
OLED_WR_Byte (0xb0 + i, OLED_CMD); //设置页地址（0~7）
OLED_WR_Byte (0x00, OLED_CMD); //设置显示位置—列低地址
OLED_WR_Byte (0x10, OLED_CMD); //设置显示位置—列高地址
for(n = 0; n < 128; n++)OLED_WR_Byte(0, OLED_DATA);
} //更新显示
}
void OLED_On(void)
{
u8 i, n;
for(i = 0; i < 8; i++)
{
OLED_WR_Byte (0xb0 + i, OLED_CMD); //设置页地址（0~7）
OLED_WR_Byte (0x00, OLED_CMD); //设置显示位置—列低地址
OLED_WR_Byte (0x10, OLED_CMD); //设置显示位置—列高地址
for(n = 0; n < 128; n++)OLED_WR_Byte(1, OLED_DATA);
} //更新显示
}
//在指定位置显示一个字符,包括部分字符
//x:0~127
//y:0~31
//mode:0,反白显示;1,正常显示
//size:选择字体 16/12
void OLED_ShowChar(u8 x, u8 y, u8 chr, u8 Char_Size)
{
unsigned char c = 0, i = 0;
c = chr - ' '; //得到偏移后的值
if(x > Max_Column - 1)
{
x = 0;
y = y + 2;
}
if(Char_Size == 16)
{
OLED_Set_Pos(x, y);
for(i = 0; i < 8; i++)
OLED_WR_Byte(F8X16[c * 16 + i], OLED_DATA);
OLED_Set_Pos(x, y + 1);
for(i = 0; i < 8; i++)
OLED_WR_Byte(F8X16[c * 16 + i + 8], OLED_DATA);
}
else
{
OLED_Set_Pos(x, y);
for(i = 0; i < 6; i++)
OLED_WR_Byte(F6x8[c][i], OLED_DATA);
}
}
//m^n函数
u32 oled_pow(u8 m, u8 n)
{
u32 result = 1;
while(n--)result *= m;
return result;
}
//显示2个数字
//x,y :起点坐标
//len :数字的位数
//size:字体大小
//mode:模式 0,填充模式;1,叠加模式
//num:数值(0~4294967295);
void OLED_ShowNum(u8 x, u8 y, u32 num, u8 len, u8 size2)
{
u8 t, temp;
u8 enshow = 0;
for(t = 0; t < len; t++)
{
temp = (num / oled_pow(10, len - t - 1)) % 10;
if(enshow == 0 && t < (len - 1))
{
if(temp == 0)
{
OLED_ShowChar(x + (size2 / 2)*t, y, ' ', size2);
continue;
}
else enshow = 1;
}
OLED_ShowChar(x + (size2 / 2)*t, y, temp + '0', size2);
}
}
//显示一个字符号串
void OLED_ShowString(u8 x, u8 y, u8* chr, u8 Char_Size)
{
unsigned char j = 0;
while (chr[j] != '\0')
{
OLED_ShowChar(x, y, chr[j], Char_Size);
x += 8;
if(x > 120)
{
x = 0;
y += 2;
}
j++;
}
}
//显示汉字
void OLED_ShowCHinese(u8 x, u8 y, u8 no)
{
u8 t, adder = 0;
OLED_Set_Pos(x, y);
for(t = 0; t < 16; t++)
{
OLED_WR_Byte(Hzk[2 * no][t], OLED_DATA);
adder += 1;
}
OLED_Set_Pos(x, y + 1);
for(t = 0; t < 16; t++)
{
OLED_WR_Byte(Hzk[2 * no + 1][t], OLED_DATA);
adder += 1;
}
}
/***********功能描述：显示显示BMP图片128×64起始点坐标(x,y),x的范围0～127，y为页的范围0～7*****************/
void OLED_DrawBMP(unsigned char x0, unsigned char y0, unsigned char x1, unsigned char y1, unsigned char BMP[])
{
unsigned int j = 0;
unsigned char x, y;
if(y1 % 8 == 0) y = y1 / 8;
else y = y1 / 8 + 1;
for(y = y0; y < y1; y++)
{
OLED_Set_Pos(x0, y);
for(x = x0; x < x1; x++)
{
OLED_WR_Byte(BMP[j++], OLED_DATA);
}
}
}
/**********************************************
//初始化SSD1306
**********************************************/
void OLED_Init(void)
{
OLED_WR_Byte(0xAE, OLED_CMD); //关闭显示
OLED_WR_Byte(0x40, OLED_CMD); //---set low column address
OLED_WR_Byte(0xB0, OLED_CMD); //---set high column address
OLED_WR_Byte(0xC8, OLED_CMD); //-not offset
OLED_WR_Byte(0x81, OLED_CMD); //设置对比度
OLED_WR_Byte(0xff, OLED_CMD);
OLED_WR_Byte(0xa1, OLED_CMD); //段重定向设置
OLED_WR_Byte(0xa6, OLED_CMD); //
OLED_WR_Byte(0xa8, OLED_CMD); //设置驱动路数
OLED_WR_Byte(0x1f, OLED_CMD);
OLED_WR_Byte(0xd3, OLED_CMD);
OLED_WR_Byte(0x00, OLED_CMD);
OLED_WR_Byte(0xd5, OLED_CMD);
OLED_WR_Byte(0xf0, OLED_CMD);
OLED_WR_Byte(0xd9, OLED_CMD);
OLED_WR_Byte(0x22, OLED_CMD);
OLED_WR_Byte(0xda, OLED_CMD);
OLED_WR_Byte(0x02, OLED_CMD);
OLED_WR_Byte(0xdb, OLED_CMD);
OLED_WR_Byte(0x49, OLED_CMD);
OLED_WR_Byte(0x8d, OLED_CMD);
OLED_WR_Byte(0x14, OLED_CMD);
OLED_WR_Byte(0xaf, OLED_CMD);
OLED_Clear();
}放一张显示效果：
