I use LSM9DS1 with STM32L433 and get strange data.

[Vladimir Lobanov]

I use LSM9DS1 with STM32L433 and get strange data.

Initialization code:

HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG4;
 
 data = 0x38; //0b00111000
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG5_XL;
 
 data = 0x38; //0b00111000
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG1_G;
 
 data = 0x80; //0b01000000
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 
 address = FIFO_CTRL;
 
 data = 0xC0; //0b11000000
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG9;
 
 data = 0x06; //0b00000110
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG1_M;
 
 data = 0xF8; //0b11111000
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG3_M;
 
 data = 0x04; //0b00000100
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_SET);
 
 
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_RESET);
 
 address = CTRL_REG4_M;
 
 data = 0x0C; //0b00001100
 
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 
 HAL_SPI_Transmit(&hspi1, &data, sizeof(address), 0x1000);
 
 HAL_GPIO_WritePin(CS_M_GPIO_Port, CS_M_Pin, GPIO_PIN_SET);

FIFO read code:

{
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 uint8_t address = FIFO_SRC | 0x80;
 uint8_t data;
 uint16_t gyro_temp[3];
 uint16_t accel_temp[3];
 uint8_t data_temp[2];
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 HAL_SPI_Receive(&hspi1, &data, sizeof(data), 0x1000);
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
 uint8_t count = data & 0x1F;
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_RESET);
 address = OUT_X_L_G | 0x80;
 HAL_SPI_Transmit(&hspi1, &address, sizeof(address), 0x1000);
 for (uint8_t i = 0; i < count; i++)
 { 
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 gyro_temp[0] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 gyro_temp[1] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 gyro_temp[2] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 accel_temp[0] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 accel_temp[1] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
 HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
 accel_temp[2] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 
 uint8_t sym_count = sprintf(wtext, "%u;%u;%u;%u;%u;%u;\r\n", accel_temp[0], accel_temp[1], accel_temp[2], gyro_temp[0], gyro_temp[1], gyro_temp[2]);
				f_write(&file, wtext, sym_count+1 , (void *)&wbytes);
 }
 HAL_GPIO_WritePin(CS_A_G_GPIO_Port, CS_A_G_Pin, GPIO_PIN_SET);
}

Can someone explain what I'm doing wrong?

[T J]

interpretation needs more information...

what is strange about the data ?

[Vladimir Lobanov]

On all channels, data jumps from 0 to ~ 60000, although the accelerometer is at rest.

For example, X axys of gyro:

[T J]

ooo,

you have negative numbers

+ and - 0

like this:

5,4,3,2,1,0,0xffff,0xfffe these are negative numbers just next to zero

I am working on the LIS3DE today, same negative numbers

[Vladimir Lobanov]

Well, if we take into account the negative values, then the amplitudes are still large (although the accelerometer is stationary)

[T J]

do you have the bytes swapped ?

i use this code

 
 ReadACC[0] = (int8_t)readLis3DEByte(OutX) & 0xFF; 
 ReadACC[1] = (int8_t)readLis3DEByte(OutY) & 0xFF; 
 ReadACC[2] = (int8_t)readLis3DEByte(OutZ) & 0xFF; 

int8_t readLis3DEByte(char address)
{
 address &= 0x3F; // 6bit address
 address += 0x80; // Read
 address += 0x40; // Auto Increment
 HAL_GPIO_WritePin(LIS3DE_nSS_GPIO_Port, LIS3DE_nSS_Pin, GPIO_PIN_RESET);
 
 transfer(address);
 char dummyByte = 0;
 char RxSPI = transfer_receive(dummyByte);
 
 HAL_GPIO_WritePin(LIS3DE_nSS_GPIO_Port, LIS3DE_nSS_Pin, GPIO_PIN_SET);
 return RxSPI;
}

void transfer(unsigned short data) {
 // Clear_SPI1_nSS_Out();
 char RxSPI;
 //read SPI SR register;
 int32_t readSPI_SR = hspi1.Instance->SR;
 
 while (!(hspi1.Instance->SR & SPI_FLAG_TXE)) ;
 *((__IO uint8_t *)&hspi1.Instance->DR) = data;
 
 while (!(hspi1.Instance->SR & SPI_FLAG_TXE)) ;
 while ((hspi1.Instance->SR & SPI_FLAG_BSY)) ;
 while ((hspi1.Instance->SR & SPI_FLAG_RXNE))
 RxSPI = hspi1.Instance->DR + readSPI_SR; // read Rx byte and discard, only clearing the buffer
// Set_SPI1_nSS_Out(); 
}
char transfer_receive(unsigned short data) {
 
 char RxSPI; 
 // Clear_SPI1_nSS_Out();
 while(!(hspi1.Instance->SR & SPI_FLAG_TXE))
 ;
 while ((hspi1.Instance->SR & SPI_FLAG_RXNE)) // load all the bytes received, only keep the last one
 RxSPI = hspi1.Instance->DR; //empty fifo
 
 *((__IO uint8_t *)&hspi1.Instance->DR) = data; // force the SPI to transceive 8 bit
 while(!(hspi1.Instance->SR & SPI_FLAG_TXE)) // wait to transmitter double buffer to shift into transmitter
 ; 
 while ((hspi1.Instance->SR & SPI_FLAG_BSY)) ; // wait for data to shift out of the processor pins
 while((hspi1.Instance->SR & SPI_FLAG_RXNE)) // load all the bytes received, only keep the last one
 RxSPI = hspi1.Instance->DR; // we only want the last byte
 // Set_SPI1_nSS_Out(); 
 
 return RxSPI;
}

[T J]

do you have a noisy power supply ?

[Vladimir Lobanov]

I read Lo and Hi bytes and convert it to int16:

HAL_SPI_Receive(&hspi1, &data_temp[0], sizeof(data_temp[0]), 0x1000);
HAL_SPI_Receive(&hspi1, &data_temp[1], sizeof(data_temp[1]), 0x1000);
gyro_temp[0] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);

[T J]

I cant see the values, so how can I help...

are you sure the value are not reversed ?

gyro_temp[0] = (int16_t) (((int16_t)data_temp[1] << 8) | data_temp[0]);
 
or 
gyro_temp[0] = (int16_t) (((int16_t)data_temp[0] << 8) | data_temp[1]);