I2C communication between two stm32 board in interrupt mode by low layer functions of STM32CUBEMX - stm32

Question

I am working on a project which needs data communication between two stm32 (stm32f103rb and stm32f429zg).
I use stm32f103rb-nucleo examples_ll (I2C _OneBoard_Communication_IT) but it works for one byte and after that, it stops working. I want it to work repetitively.
the code structure is exactly in the way the example is written in the folder related to stm32cubemx repository.
I don't know how to make it work in a loop and by pressing the button, communication gets done every time I push the master and slave push buttons.
I have put the master completion callback function here :
void Master_Complete_Callback(void)
{
if(ubNbDataToReceive == 3)
{
/* Prepare the generation of a Non ACKnowledge condition after next received bytes */
LL_I2C_AcknowledgeNextData(I2C1, LL_I2C_NACK);
/* Read character in Receive Data register.
RXNE flag is cleared by reading data in RXDR register */
aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
ubNbDataToReceive--;
/* Disable Buffer Interrupts */
LL_I2C_DisableIT_BUF(I2C1);
}
else if(ubNbDataToReceive == 2)
{
/* Generate Stop condition */
LL_I2C_GenerateStopCondition(I2C1);
/* Read character from Receive Data register.
RXNE flag is cleared by reading data in RXDR register */
aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
ubNbDataToReceive--;
/* Read character from shift register.
RXNE flag is cleared by reading data in RXDR register */
aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
ubNbDataToReceive--;
}
else
{
if(ubNbDataToReceive > 0)
{
/* Read character from shift register.
RXNE flag is cleared by reading data in RXDR register */
aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C2);
/* Update ubNbDataToReceive variable */
ubNbDataToReceive--;
}
}
if(ubNbDataToReceive == 0)
{
/* (1) Disable I2C1 transfer event/error interrupts:
* - Disable Events Interrupt
* - Disable Error interrupts
*/
LL_I2C_DisableIT_EVT(I2C1);
LL_I2C_DisableIT_ERR(I2C1);
LL_I2C_EnableIT_EVT(I2C1);
LL_I2C_EnableIT_ERR(I2C1);
/* Read Received character.
RXNE flag is cleared by reading of RXDR register */
if(aReceiveBuffer[ubReceiveIndex-1] == SLAVE_BYTE_TO_SEND)
{
/* Turn LED2 On:
* - Expected byte has been received
* - Master Rx sequence completed successfully
*/
//LED_On();
HAL_UART_Transmit_IT(&huart2,(uint8_t*)"#Data transfer is OK!$",strlen("#Data transfer is OK!$"));
ubNbDataToTransmit = sizeof(SLAVE_BYTE_TO_SEND);
ubNbDataToReceive = sizeof(SLAVE_BYTE_TO_SEND);
}
else
{
/* Call Error function */
Error_Callback();
}
}
}
it is easily understood that the end of the transmission process is when I add HAL_UART function to send to serial port the transmission completion.
but after this time , it works one more time and after that it stops.
I have checked the oscilloscope signal show and after the second time transmission SCL pin gets LOW .
Thanks

Answer 1

Did not use LL for a long time, but isnt I2C interrupt disabled after single transfer with LL_I2C_DisableIT_EVT(I2C1);?? Make sure to enable it again before next transmission.

Answer 2

There is such a thing that two master devices cannot communicate each other via I2C bus. Because master devices do not have DEVICE_ADDRESS. Master devices can communicate only slave devices.