我正在使用STM32f030c8在24c04开发用于I2C eeprom的库。我的读写功能有效，但是当我在写入eeprom后立即尝试读取时，eeprom doest会返回任何数据。但是我可以马上连续写一下。只有在写入语句后才能读取问题。我尝试启用和禁用I2C使能位，但问题仍然存在。有人可以告诉我这是什么问题吗
void main()
{
Configure_GPIO_I2C2();
Configure_I2C2_Master(0xA0,1);
I2C_WriteByte(5,'k');
charr= I2C_ReadByte(5);//the program get stuck here because no byte is
//received from eeprom
UART_Send_String(1,&charr);
}
void I2C_WriteByte(uint8_t addr,uint8_t bytetowrite)
{
I2C2->ISR=0x01;
I2C2_StartWrite(2);//start
I2C2->TXDR = addr;//write addr
while(!(I2C2->ISR & I2C_ISR_TXE));
//I2C2_StartWrite(1);
I2C2->TXDR = bytetowrite;
while(!(I2C2->ISR & I2C_ISR_TXE));
I2C2->CR2 |= I2C_CR2_STOP;//stop
while(I2C2->CR2 & I2C_CR2_STOP);
}
uint8_t I2C_ReadByte(uint8_t byteToRead)
{
I2C2->ISR=0x01;
I2C2_StartWrite(1);
I2C2->TXDR = byteToRead;
while(!(I2C2->ISR & I2C_ISR_TXE));
I2C2_StartRead(1);
while(!(I2C2->ISR & I2C_ISR_RXNE));
UART_Send_String(1,"r strt");
uint8_t recv_data=I2C2->RXDR;
I2C2->CR2 |= I2C_CR2_STOP;
while(I2C2->CR2 & I2C_CR2_STOP);
return recv_data;
}
void Configure_GPIO_I2C2(void)
{
RCC->AHBENR |= RCC_AHBENR_GPIOFEN;
GPIOF->MODER |= (2<<12) | (2<<14);
GPIOF->OTYPER |= GPIO_OTYPER_OT_6 | GPIO_OTYPER_OT_7;
GPIOF->OSPEEDR &= ~(1<<12);
GPIOF->OSPEEDR &= ~(1<<14);
GPIOF->PUPDR &= ~(1<<12);
GPIOF->PUPDR &= ~(1<<12);
}
void Configure_I2C2_Master(uint8_t slave_addr,uint8_t no_of_bytes)
{
RCC->APB1ENR |= RCC_APB1ENR_I2C2EN;
/* (1) timing register value is computed with the AN4235 xls file,
fast Mode @400kHz with I2CCLK = 48MHz, rise time = 140ns, fall time = 40ns */
I2C2->CR1 &= ~I2C_CR1_PE;
I2C2->TIMINGR |= (uint32_t)0x00B01A4B; /* (1) */
I2C2->CR2 |= (uint8_t)slave_addr;
I2C2->CR2 |= no_of_bytes<<16;
I2C2->CR1 |= I2C_CR1_PE;
//NVIC_SetPriority(I2C2_IRQn, 0); /* (7) */
//NVIC_EnableIRQ(I2C2_IRQn); /* (8) */
}
void I2C2_StartWrite(int bytesToWrite)
{
I2C2->CR2 &= ~I2C_CR2_RD_WRN;
I2C2->CR2 |= bytesToWrite<<16;
I2C2->CR2 |= I2C_CR2_START;
while(I2C2->CR2 & I2C_CR2_START);
}
void I2C2_StartRead(int bytesToRead)
{
I2C2->CR2 |= I2C_CR2_RD_WRN;
I2C2->CR2 |= bytesToRead<<16;
I2C2->CR2 |= I2C_CR2_START;
while(I2C2->CR2 & I2C_CR2_START);
}
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