I2C & SPI not working together (STM32F303K8)

[Linkpad]

Hi, I am trying to simply output information from an I2C device (DS1307 real time clock) to an SPI screen (ST7789) I have tested the code & libraries for the separate devices and they work but as soon as I try adding any SPI commands to the main.c the output just crashes (simple UART message) as below:-

"DS1307_Init(&hi2c1);
/* To test leap year correction. */
DS1307_SetTimeZone(+8, 00);
DS1307_SetDate(12);
DS1307_SetMonth(7);
DS1307_SetYear(2023);
DS1307_SetDayOfWeek(4);
DS1307_SetHour(9);
DS1307_SetMinute(00);
DS1307_SetSecond(00);
const char *DAYS_OF_WEEK[7] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" };
HAL_UART_Transmit(&huart2, "DS1307 innit", sizeof"DS1307 innit", 1000);
HAL_Delay(200);
ST7789_Init();
HAL_UART_Transmit(&huart2, "ST7789 innit", sizeof"ST7789 innit", 1000);
"

As soon as i add the 'ST7789_Init();' command everything seizes to work and all I get on the UART monitor is "DS1307 innit" not the "ST7789 innit". I have tried all the different SPI & I2C settings disabling and enabling interrupts and no luck. Is there an SPI setting which can conflict with I2C? 

[Foued_KH]

Hello @Linkpad, 

I think there isn't an SPI setting which can conflict with I2C.
You need to debug you code to catch the issue source.

Foued

[raptorhal2]

Any chance the SPI uses the same pins as USART2 ?

[######]

As @raptorhal2 mentioned, the likelihood is a pin definition clash. 

According to Datasheet DS9866 Page 39:

PA14 can be either alternate function I2C1_SDA or USART2_TX as well as PA15 being I2C1_SCL, SPI1_NSS and USART2_RX.

PB3 and PB4 also has a similar clash between SPI1 and USART2.

What are your pin definitions?

[Foued_KH]

Hi @Linkpad , 

Could you please share your .ioc file ?

Foued

[Linkpad]

Hi Foued,

Not too worry the only way I have managed to get the I2C to work currently is by using both SPI & I2C in DMA mode I am guessing there needs to be either interrupts, DMA or RTOS when there are several devices talking to each other simultaneously such as I2C & SPI? I think the trouble is most of the examples I have seen just seem to show either SPI TFT screen code or I2C code and not a combination...