STM32F429I_DISC1 board and SPI COM with L3GD20(onboard *gyroscope)

[SKAŞ.1]

Hello folks,

Today, I am trying to use SPI communication on my board. I saw that there is a gyroscope on my board. So, I thought it's a good idea to use this device as an example. Since it's already routed it up, I cannot mess up with connections, etc.

Here is the thing, I don't want to install additional libraries. Instead, I want to create/program this example via what everybody starts with. I use CubeIDE. CubeIDE already gives me a bunch of predefined functions with HAL and I assume that function is more than enough to complete this project.

I guess I am able to use SPI since the function returns HAL_OK. However, I cannot read any value from either x, y, or z.

These are the pins according to the datasheet.

This is an SPI configuration made by Cube automatically. I didn't change anything from here.

I upload the program in case someone wants to look at it.

I found these links useful for understanding how they made the chip select SPI, transmit-receive kinda stuff.

https://github.com/MaJerle/stm32f429/tree/master/28-STM32F429_L3GD20

-> This guy uses SPI to communicate

https://www.instructables.com/Learning-About-the-L3GD20-Breakout-Board/

-> This guy uses I2C to communicate

I use SPI but, I'm guessing Majerle doesn't have the SPI_Receive function in DATA_Read.

anyway, that info is a little irrelevant.

I want to learn from my mistakes and get better at this stuff.

THANKS for your attention,

Kind Regards.

*I set pin A1 for interrupt, but I didn't use it for interrupt. Is that the problem? If it's the case then, that might be a very rookie mistake.😬

[SKAŞ.1]

I checked and accidentally, I made PC1 as input. I change that value with GPIO_Output with default HIGH.

I put a control array to see if I could write anything on-chip. Sadly, the HAL_I2C_Receive function turns nothing (0).

[SKAŞ.1]

I realize that I cannot always send data through TX or RX, people make chip select high and low every time. So I change my initialize part like this

  // Manually Create L3GD20 via SPI!
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x20;
  gyroBufferTx[1] = 0x0F;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);	// L3GD20 PowerBit
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x20 | 0x80;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 1, 100);
  HAL_SPI_Receive(&hspi5, *gyroBufferRx, 1, 100);
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  val_Ctrl[0] = gyroBufferRx[0];
  /////////
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x23;
  gyroBufferTx[1] = 0x00;	// 0x00 for scale 250, 0x10 for scale 500, 0x20 for scale 2000
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);	// Scaling
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x23 | 0x80;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 1, 100);
  HAL_SPI_Receive(&hspi5, *gyroBufferRx, 1, 100);
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  val_Ctrl[4] = gyroBufferRx[0];
  /////////
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x21;
  gyroBufferTx[1] = 0x00;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);	// Set high-pass filter settings.
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x21 | 0x80;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 1, 100);
  HAL_SPI_Receive(&hspi5, *gyroBufferRx, 1, 100);
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  val_Ctrl[1] = gyroBufferRx[0];
  /////////
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x22;
  gyroBufferTx[1] = 0x08;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);	// Set high-pass filter settings.
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x22 | 0x80;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 1, 100);
  HAL_SPI_Receive(&hspi5, *gyroBufferRx, 1, 100);
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  val_Ctrl[2] = gyroBufferRx[0];
  /////////
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x22;
  gyroBufferTx[1] = 0x10;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);	// Enable high-pass filter settings.
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, RESET);  // Chip Select LOW!
  gyroBufferTx[0] = 0x22 | 0x80;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 1, 100);
  HAL_SPI_Receive(&hspi5, *gyroBufferRx, 1, 100);
  val_Ctrl[3] = gyroBufferRx[0];
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_1, GPIO_PIN_SET);	// Chip Select HIGH!
 
  // Manually we should create L3GD20 SPI communication

[TDK]

  gyroBufferTx[0] = 0x20;
  gyroBufferTx[1] = 0x0F;
  HAL_SPI_Transmit(&hspi5, *gyroBufferTx, 2, 100);

This seems wrong. How is gyroBufferTx defined? Probably want to pass gyroBufferTx and not *gyroBufferTx. It should be giving you a warning during compiling.

[SKAŞ.1]

/* USER CODE BEGIN PV */

uint8_t gyroBufferTx[8];

uint8_t gyroBufferRx[8];

/* USER CODE END PV */

under private variable section

[SKAŞ.1]

When I seeking around,

https://github.com/MaJerle this guy set his board Prescaler to 32. Mine was initially set to 128, I changed as 32 too.

[TDK]

So yes, passing "*gyroBufferTx" will not work here and should be giving you an error during compiling. You need to pass "gyroBufferTx" which is the pointer to the buffer. *gyroBufferTx is the value of the first element.

[SKAŞ.1]

WONDERFUL!!

I cannot thanks enough, thanks to you (and all the community) my learning process got speed!

THANKS AGAIN!