GD32F330 硬件SPI CS过短问题

1. CS过短导致写SPI出现问题

  spi_i2s_data_transmit(SPI1, byte);
  while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_TBE));

LCD_CS是用户软件控制的芯片使能脚。
实际发送了1.5bit后，SPI_FLAG_TBE已置位。因此判断SPI_FLAG_TBE会导致 LCD_CS过短。

2. 改善

  while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_TBE));
  spi_i2s_data_transmit(SPI1, byte);
  while(SET == spi_i2s_flag_get(SPI1, SPI_FLAG_TRANS)); //加此行，改善

3. 完整代码

void SPI1_SendByte(uint8_t byte)
{   
  while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_TBE));
  spi_i2s_data_transmit(SPI1, byte);
  while(SET == spi_i2s_flag_get(SPI1, SPI_FLAG_TRANS));
}

uint8_t SPI1_ReadByte(uint8_t byte)
{  
  while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_TBE));
  spi_i2s_data_transmit(SPI1, byte);
  while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_RBNE));
  return (uint8_t)spi_i2s_data_receive(SPI1);
}

void SPI1_SendBytes(const uint8_t *buf, uint16_t length)
{
  uint16_t i;
  
  for(i=0;i<length;i++)
  {
    while(RESET == spi_i2s_flag_get(SPI1, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI1, buf[i]);
  }  
  while(SET == spi_i2s_flag_get(SPI1, SPI_FLAG_TRANS));
}