2019-08-14 04:16发布
怕水的鱼 发表于 2017-9-1 10:58 给点建议啊 大神们
huanghan 发表于 2017-9-1 11:14 应答有是有的吧,
怕水的鱼 发表于 2017-9-1 11:16 等待应答的就是第九个时钟啊
最多设置5个标签!
void Delayus(uint32_t counter) //1 1US 8 2US 24 4US
{
uint32_t i;
for(i =0;i<counter;i++)
{
__NOP;
}
}
//3õê¼»ˉIIC
void IIC_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);//ê1ÄüGPIOBê±Öó
//GPIOB8,B93õê¼»ˉéèÖÃ
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//ÆÕí¨êä3öÄ£ê½
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;//íÆíìêä3ö
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;//100MHz
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//
GPIO_Init(GPIOA, &GPIO_InitStructure);//3õê¼»ˉ
IIC_SDA_ON;
IIC_SCL_ON;
}
//2úéúIICÆeê¼DÅoÅ
void IIC_Start(void)
{
SDA_OUT(); //sdaÏßêä3ö
IIC_SDA_ON;
IIC_SCL_ON;
Delayus(130);//4us
IIC_SDA_OFF;//START:when CLK is high,DATA change form high to low
Delayus(130);
IIC_SCL_OFF;
//ÇˉסI2C×üÏߣ¬×¼±¸·¢Ëí»ò½óêÕêy¾Y
}
//2úéúIICí£Ö1DÅoÅ
void IIC_Stop(void)
{
SDA_OUT();//sdaÏßêä3ö
IIC_SCL_OFF;
IIC_SDA_OFF;//STOP:when CLK is high DATA change form low to high
Delayus(130);
IIC_SCL_ON;
IIC_SDA_ON;//·¢ËíI2C×üÏß½áêøDÅoÅ
Delayus(130);
}
//μè′yó|′eDÅoÅμ½à′
//·μ»ØÖμ£o1£¬½óêÕó|′eê§°ü
// 0£¬½óêÕó|′e3é1|
uint8_t IIC_Wait_Ack(void)
{
uint8_t ack;
uint32_t ucErrTime=0;
IIC_SDA_ON;
Delayus(500);
IIC_SCL_ON;
Delayus(130);
SDA_IN(); //SDAéèÖÃÎaêäèë
while(IIC_SDA_IN)
{
ucErrTime++;
if(ucErrTime>2500)
{
//IIC_Stop();
return 1;
}
}
IIC_SCL_OFF;//ê±Öóêä3ö0
Delayus(130);
return 0;
// ack = (IIC_SDA_IN); // Read ACK state from Slave
// IIC_SCL_OFF; // SCL = 0
// if (ack) // Return ACK state to calling app
// return (1);
// else
// return (0);
}
//2úéúACKó|′e
void IIC_Ack(void)
{
IIC_SCL_OFF;
SDA_OUT();
IIC_SDA_OFF;
Delayus(130);
IIC_SCL_ON;
Delayus(130);
IIC_SCL_OFF;
}
//2»2úéúACKó|′e
void IIC_NAck(void)
{
IIC_SCL_OFF;
SDA_OUT();
IIC_SDA_ON;
Delayus(130);
IIC_SCL_ON;
Delayus(130);
IIC_SCL_OFF;
}
//IIC·¢Ëíò»¸ö×Ö½ú
//·μ»Ø′ó»úóDÎTó|′e
//1£¬óDó|′e
//0£¬ÎTó|′e
void IIC_Send_Byte(uint8_t txd)
{
uint8_t t;
SDA_OUT();
IIC_SCL_OFF;//à-μíê±Öó¿aê¼êy¾Y′«êä
for(t=0;t<8;t++)
{
if((txd&0x80)>>7)
{
IIC_SDA_ON;
}
else
{
IIC_SDA_OFF;
}
txd<<=1;
Delayus(65); //¶ÔTEA5767Õaèy¸öÑóê±¶¼êDZØDëμÄ
IIC_SCL_ON;
Delayus(130);
IIC_SCL_OFF;
Delayus(65);
}
}
//¶á1¸ö×Ö½ú£¬ack=1ê±£¬·¢ËíACK£¬ack=0£¬·¢ËínACK
uint8_t IIC_Read_Byte(unsigned char ack)
{
unsigned char i,receive=0;
SDA_IN();//SDAéèÖÃÎaêäèë
for(i=0;i<8;i++)
{
IIC_SCL_OFF;
Delayus(130);
IIC_SCL_ON;
receive<<=1;
if(IIC_SDA_IN)receive++;
Delayus(130);
}
if (!ack)
IIC_NAck();//·¢ËínACK
else
IIC_Ack(); //·¢ËíACK
return receive;
}
应答有是有的吧,
不行就不要用模拟,用I2C模块
等待应答的就是第九个时钟啊
没有看出来哪里混乱,是你看了吧,为什么接收应答要那么长时间,应该看这函,是这个函里里Delayus()产生的
uint8_t IIC_Wait_Ack(void)
{
uint8_t ack;
uint32_t ucErrTime=0;
IIC_SDA_ON;
Delayus(500); //
IIC_SCL_ON;
Delayus(130);
SDA_IN(); //SDAéèÖÃÎaêäèë
while(IIC_SDA_IN)
{
ucErrTime++;
if(ucErrTime>2500)
{
//IIC_Stop();
return 1;
}
}
IIC_SCL_OFF;//ê±Öóêä3ö0
Delayus(130);
return 0;
// ack = (IIC_SDA_IN); // Read ACK state from Slave
// IIC_SCL_OFF; // SCL = 0
// if (ack) // Return ACK state to calling app
// return (1);
// else
// return (0);
}
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