Hello all,
I have serious problem with SPI2 on STM32H745 using interrupts.
First I try system with polling:
uint8_t Send(data)
{
*((uint8_t*)&SPI2->TXDR) = data;
while((SPI2->SR & SPI_SR_RXP) == 0)
{
}
return *((uint8_t*)&SPI2->RXDR);
}
All works as expected, I send correctly, receive what I expect.
But polling is not the solution, so I set up system to fire interrupt when byte is available:
uint8_t Send(data)
{
*((uint8_t*)&SPI2->TXDR) = data;
SPI2->IER = SPI_IER_RXPIE;
waitSignal();
return *((uint8_t*)&SPI2->RXDR);
}
void SPI2_IRQHandler(void)
{
SPI2->IER = 0;//disable interrupt
sendSignal();
}
What happens is that system does not care that I disabled all SPI interrupts and it goes to isr vector constantly! And system stalls ofcourse.
There is notice in errata about spurious TXP. So maybe they are related?
So I tried a work around:
uint8_t Send(data)
{
*((uint8_t*)&SPI2->TXDR) = data;
NVIC_EnableIRQ(SPI2_IRQn);
SPI2->IER = SPI_IER_RXPIE;
waitSignal();
return *((uint8_t*)&SPI2->RXDR);
}
void SPI2_IRQHandler(void)
{
//
SPI2->IER = 0;//disable interrupt
NVIC_DisableIRQ(SPI2_IRQn);
sendSignal();
}
Now system fires one interrupt, disable works, BUT I get nonsence in RXDR.
I put osciloscope to work and see, that RXP flag is fired too early! And ofcourse this makes bad data in RXDR.
My question is: how should it work then? Is there another workaround? I need only 1 byte, should I use DMA for this???
