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我用STM32mini板燒進去程序,為什么OLED 屏幕直接就滅了,然后右下角只有提示燈再閃,
OLED 屏幕全滅
#include "IIC.h"
void IIC_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB, ENABLE ); //使能GPIOB時鐘
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP ; //推挽輸出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
GPIO_SetBits(GPIOB, GPIO_Pin_6 | GPIO_Pin_7); //PB6,PB7 輸出高
}
//產生IIC起始信號
void IIC_Start(void)
{
SDA_OUT(); //sda線輸出
IIC_SDA = 1;
IIC_SCL = 1;
delay_us(4);
IIC_SDA = 0; //START:when CLK is high,DATA change form high to low
delay_us(4);
IIC_SCL = 0; //鉗住I2C總線,準備發送或接收數據
}
//產生IIC停止信號
void IIC_Stop(void)
{
SDA_OUT();//sda線輸出
IIC_SCL = 0;
IIC_SDA = 0; //STOP:when CLK is high DATA change form low to high
delay_us(4);
IIC_SCL = 1;
IIC_SDA = 1; //發送I2C總線結束信號
delay_us(4);
}
//等待應答信號到來
//返回值:1,接收應答失敗
// 0,接收應答成功
u8 IIC_Wait_Ack(void)
{
u8 ucErrTime = 0;
SDA_IN(); //SDA設置為輸入
IIC_SDA = 1;
delay_us(1);
IIC_SCL = 1;
delay_us(1);
while(READ_SDA)
{
ucErrTime++;
if(ucErrTime > 250)
{
IIC_Stop();
return 1;
}
}
IIC_SCL = 0; //時鐘輸出0
return 0;
}
//產生ACK應答
void IIC_Ack(void)
{
IIC_SCL = 0;
SDA_OUT();
IIC_SDA = 0;
delay_us(2);
IIC_SCL = 1;
delay_us(2);
IIC_SCL = 0;
}
//不產生ACK應答
void IIC_NAck(void)
{
IIC_SCL = 0;
SDA_OUT();
IIC_SDA = 1;
delay_us(2);
IIC_SCL = 1;
delay_us(2);
IIC_SCL = 0;
}
//IIC發送一個字節
//返回從機有無應答
//1,有應答
//0,無應答
void IIC_Send_Byte(u8 txd)
{
u8 t;
SDA_OUT();
IIC_SCL = 0; //拉低時鐘開始數據傳輸
for(t = 0; t < 8; t++)
{
//IIC_SDA=(txd&0x80)>>7;
if((txd & 0x80) >> 7)
IIC_SDA = 1;
else
IIC_SDA = 0;
txd <<= 1;
delay_us(2); //對TEA5767這三個延時都是必須的
IIC_SCL = 1;
delay_us(2);
IIC_SCL = 0;
delay_us(2);
}
}
//讀1個字節,ack=1時,發送ACK,ack=0,發送nACK
u8 IIC_Read_Byte(unsigned char ack)
{
unsigned char i, receive = 0;
SDA_IN();//SDA設置為輸入
for(i = 0; i < 8; i++)
{
IIC_SCL = 0;
delay_us(2);
IIC_SCL = 1;
receive <<= 1;
if(READ_SDA)
receive++;
delay_us(1);
}
if (!ack)
IIC_NAck();//發送nACK
else
IIC_Ack(); //發送ACK
return receive;
}
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