Posted on June 19, 2015 at 07:09
Hi i would like you guys to look into my code so that i get a better understanding
Actually i have a master slave communication between two controllers ( STM32 is the slave, it receives packets of about 255 bytes from the other controller and transmits only ACKs of around 10 bytes )
This is the UART Sendstring code which enables the transmit interrupt to send a packet of 10 bytes. We are disabling the receive interrupt while transmitting is it needed ?
void
USART_SendString(USART_TypeDef* USARTx,
CUInt16 u16len
){
USART_ITConfig(USART1, USART_IT_RXNE, DISABLE );
//Disable receive interrupt
USART_ClearITPendingBit(USART1, USART_IT_RXNE);
//Clear pending interrupt bit
while
(cTlen);
//if next buffer comes wait till previous buffer is completely transmitted
//udelay(500);
cTlen = u16len;
memset
(cTX_Buff, 0x00,
sizeof
(cTX_Buff));
//Clear transmit buffer
memcpy
((
char
*)&cTX_Buff, (
char
*)&cSend_Buff, u16len);
//Copy send buff to tx buff
cTptr = cComm_Len = 0;
USARTx->DR = (cTX_Buff[cTptr++] & (uint16_t)0x01FF);
//Stm32 standard lib
USART_ITConfig(USART1, USART_IT_TXE, ENABLE );
//Enable transmit interrupt
}
Here below is the ISR for the transmission.. Once transmission is done we are re-enabling the receive interrupt and disabling the transmit interrupt
if
(USART_GetITStatus( USART1 , USART_IT_TXE ) != RESET )
{
//Transmit Data to UART till cTptr is less than data length and less than TX_Buff size
if
((cTptr < cTlen) && (cTptr <= TX_BUFF_SIZE))
{
//Send Data on UART
USART1->DR = (cTX_Buff[cTptr++] & (uint16_t)0x01FF);
//Stm32 standard peripheral library code
}
else
{
USART_ITConfig(USART1, USART_IT_TXE, DISABLE);
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE );
USART_ClearITPendingBit(USART1, USART_IT_TC);
cTlen = 0;
}
}
}
Is the approach used correct or is there is any flaw
