STM32硬件I2C 事件中断凭空多出个BTF位

lzly0302

用硬件I2C通信时，容易出现事件中断中多出个BTF位，不知道各位大大实际使用中是否有碰到，该怎么解决

笑笑我笑了

用标准库读事件就可以了，用HAL库更方便。

------------------------------------------摘自参考手册-----------------------------------------------------
EV5: SB=1, cleared by reading SR1 register followed by writing DR register with Address.
EV6: ADDR=1, cleared by reading SR1 register followed by reading SR2.
EV8_1: TxE=1, shift register empty, data register empty, write Data1 in DR.
EV8: TxE=1, shift register not empty, . data register empty, cleared by writing DR register
EV8_2: TxE=1, BTF = 1, Program Stop request. TxE and BTF are cleared by hardware by the Stop condition
EV9: ADD10=1, cleared by reading SR1 register followed by writing DR register.

lzly0302

笑笑我笑了 发表于 2017-8-30 13:22
用标准库读事件就可以了，用HAL库更方便。

------------------------------------------摘自参考手册----- ...

uint32_t I2C_GetLastEvent(I2C_TypeDef* I2Cx)
{
  uint32_t lastevent = 0;
  uint32_t flag1 = 0, flag2 = 0;

  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));

  /* Read the I2Cx status register */
  flag1 = I2Cx->SR1;
  //DISABLE_GLOBAL_INTERRUPT();
  flag2 = I2Cx->SR2;
// ENABLE_GLOBAL_INTERRUPT();
  flag2 = flag2 << 16;

  /* Get the last event value from I2C status register */
  lastevent = (flag1 | flag2) & FLAG_Mask;

  /* Return status */
  return lastevent;
}
是用这段代码么，感觉效果一样的还是会出现问题

笑笑我笑了

lzly0302 发表于 2017-8-30 13:32
uint32_t I2C_GetLastEvent(I2C_TypeDef* I2Cx)
{
  uint32_t lastevent = 0;

代码是一样的。
这种情况我一般会用逻辑分析仪看一看。