Write/Read SPI directly (no ISR) using LL

[TheRaprus]

Hallo to everybody.

Still working on SPI&Display  adapting a code for M4 (see Different data after the 1st transfer using SPI via DMA ).

I need to write only one byte at a time due to control pins of display.

Starting from a NUCLEO-H563ZI and LL example "SPI_OneBoard_HalfDuplex_IT_Init" (it work!) I'trying to do it without interrupt. So, the code is like this:

Spoiler

LL_SPI_SetFIFOThreshold(SPI1, LL_SPI_FIFO_TH_01DATA);
LL_SPI_SetFIFOThreshold(SPI2, LL_SPI_FIFO_TH_01DATA);
LL_SPI_Enable(SPI1);LL_SPI_Enable(SPI2);
while(!LL_SPI_IsActiveFlag_TXP(SPI1))    {}
LL_SPI_TransmitData8 (SPI1, 0x55);
LL_SPI_StartMasterTransfer(SPI1);
//(wait for RXP flag)
val = LL_SPI_ReceiveData8(SPI2);  //or below

while (!LL_SPI_IsActiveFlag_TXC(SPI1))    {}

val = LL_SPI_ReceiveData8(SPI2); //other place!

Using step-by-step debugger I read 0x55 in SPI2_RXDR register, but got a 0 if I read it (removing the breackpoint and leave the program running). The RXP flag is cleared immediately after a simple __NOP() instruction and RXDR is immediately set to 0.
Again, I enabled the SPI2 RX interrupt, I reach the ISR, execute the example's routine
aRxBuffer[ubReceiveIndex++] = LL_SPI_ReceiveData8(SPI2);
but aRxBuffer[0] is = 0. (ubReceiveIndex is 1).

Can someone help me?

@MOBEJ  have you some solutions?

[TheRaprus · Accepted solution]

Solved:

Sometime a simple"rebuild all" (cleaning the .launch file too) is enought.

Discovered using the IAR IDE instead the Cube, then test it again...