i'm trying to establish an UART connection between STM32F4 and Raspberry Pi 3 to send motion sensor data.
STM32 C code:
/* Includes ------------------------------------------------------------------*/
#include "stm32f4_discovery.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
int8_t polje[4];
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
void delay(uint32_t delay) {
while(delay--);
}
// write to SPI1
void SPI1_Write(int8_t data)
{
// short delay
volatile int d = 500;
while(d--);
while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET){}
SPI_I2S_SendData(SPI1, data);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET){}
SPI_I2S_ReceiveData(SPI1);
}
// read from SPI1
int8_t SPI1_Read()
{
// short delay
volatile int d = 500;
while(d--);
while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET){}
SPI_I2S_SendData(SPI1, 0x00);
while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET){}
return SPI_I2S_ReceiveData(SPI1);
}
void initSPI1(void)
{
// RCC
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
// PA5, PA6, PA7 for MISO, MOSI, and SCLK
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);
// SPI1 INIT
SPI_InitTypeDef spi;
spi.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
spi.SPI_Mode = SPI_Mode_Master;
spi.SPI_DataSize = SPI_DataSize_8b;
spi.SPI_CPOL = SPI_CPOL_Low;
spi.SPI_CPHA = SPI_CPHA_1Edge;
spi.SPI_NSS = SPI_NSS_Soft;
spi.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
spi.SPI_FirstBit = SPI_FirstBit_MSB;
spi.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &spi);
// SPI1 ENABLE
SPI_Cmd(SPI1, ENABLE);
}
void initMotionSensor()
{
// RCC
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
// PE3 for slave select
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
// configure and start sensor
GPIO_InitTypeDef ss;
ss.GPIO_Pin = GPIO_Pin_3;
ss.GPIO_Mode = GPIO_Mode_OUT;
ss.GPIO_OType = GPIO_OType_PP;
ss.GPIO_PuPd = GPIO_PuPd_NOPULL;
ss.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOE, &ss);
GPIO_SetBits(GPIOE, GPIO_Pin_3);
// Aktiviram slave
//delay(500);
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
// Zapisem inicializacijo senzorja
// Zapisem 0x47 na naslov 0x20
SPI1_Write(0x20);
SPI1_Write(0x47);
GPIO_SetBits(GPIOE, GPIO_Pin_3);
//delay(500);
}
void initUSART1()
{
// RCC
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
// USART1 init
USART_InitTypeDef USART_InitStruct;
USART_InitStruct.USART_BaudRate = 9600;
USART_InitStruct.USART_WordLength = USART_WordLength_8b;
USART_InitStruct.USART_StopBits = USART_StopBits_1;
USART_InitStruct.USART_Parity = USART_Parity_No;
USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStruct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
USART_Init(USART1, &USART_InitStruct);
// USART1 enable
USART_Cmd(USART1, ENABLE);
// PB6 and PB7 for USART1 Tx and Rx
GPIO_InitTypeDef usart_dev;
usart_dev.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
usart_dev.GPIO_Mode = GPIO_Mode_AF;
usart_dev.GPIO_OType = GPIO_OType_PP;
usart_dev.GPIO_Speed = GPIO_Speed_50MHz;
usart_dev.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOB, &usart_dev);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource6,GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource7,GPIO_AF_USART1);
}
void initDMA2()
{
// RCC
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
// init DMA2
DMA_InitTypeDef DMA_InitStructure;
DMA_InitStructure.DMA_Channel = DMA_Channel_4;
DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t) polje;
DMA_InitStructure.DMA_BufferSize = 4;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) &(USART1 -> DR);
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA2_Stream7, &DMA_InitStructure);
// enable USART1 DMA Tx
USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);
// enable DMA2 stream
DMA_Cmd(DMA2_Stream7, ENABLE);
}
/**
* @brief Main program
* @param None
* @retval None
*/
int main(void)
{
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
// led init
GPIO_InitTypeDef leds;
leds.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
leds.GPIO_Mode = GPIO_Mode_OUT;
leds.GPIO_OType = GPIO_OType_PP;
leds.GPIO_PuPd = GPIO_PuPd_NOPULL;
leds.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOD, &leds);
// SPI1
initSPI1();
// LIS motion sensor
initMotionSensor();
// USART1
initUSART1();
// DMA2
initDMA2();
while (1)
{
// read x1
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
SPI1_Write(0x29 | 0x80);
volatile int8_t x1 = SPI1_Read();
GPIO_SetBits(GPIOE, GPIO_Pin_3);
delay(500);
// read y1
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
SPI1_Write(0x2B | 0x80);
volatile int8_t y1 = SPI1_Read();
GPIO_SetBits(GPIOE, GPIO_Pin_3);
if (x1 < -5) {
// Vklopi ledico
GPIO_SetBits(GPIOD, GPIO_Pin_12);
delay(500);
GPIO_ResetBits(GPIOD, GPIO_Pin_12);
}
if (x1 > 5) {
// Vklopi drugo ledico
GPIO_SetBits(GPIOD, GPIO_Pin_14);
delay(500);
GPIO_ResetBits(GPIOD, GPIO_Pin_14);
}
if (y1 < -5) {
// Vklopi ledico
GPIO_SetBits(GPIOD, GPIO_Pin_15);
delay(500);
GPIO_ResetBits(GPIOD, GPIO_Pin_15);
}
if (y1 > 5) {
// Vklopi drugo ledico
GPIO_SetBits(GPIOD, GPIO_Pin_13);
delay(500);
GPIO_ResetBits(GPIOD, GPIO_Pin_13);
}
delay(500);
// read x
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
SPI1_Write(0x29 | 0x80);
volatile int8_t x2 = SPI1_Read();
GPIO_SetBits(GPIOE, GPIO_Pin_3);
delay(500);
// read y
GPIO_ResetBits(GPIOE, GPIO_Pin_3);
SPI1_Write(0x2B | 0x80);
volatile int8_t y2 = SPI1_Read();
GPIO_SetBits(GPIOE, GPIO_Pin_3);
delay(500);
polje[0] = x1;
polje[1] = x2;
polje[2] = y1;
polje[3] = y2;
delay(500);
}
}
Raspberry Pi code:
import time
import ctypes
import serial
import sys
from binascii import hexlify
ser = serial.Serial(
port='/dev/ttyS0',
baudrate=9600,
parity=serial.PARITY_NONE,
stopbits=serial.STOPBITS_ONE,
bytesize=serial.EIGHTBITS,
timeout=1,
dsrdtr=False
)
counter = 0
if (ser.isOpen() == False):
ser.open()
#Flush before receiving or sending any data
ser.flushInput()
ser.flushOutput()
while 1:
x = ser.read()
print (hexlify(x))
time.sleep(0.3)
I already enabled the serial port interface on Raspberry Pi and disabled the terminal over serial option. I'm sure that the code on STM32 works, because I tried it with another STM32 as a receiver. I connected 2 GND pins together and STM32's Tx (PB6 in my case) to RasPi Rx (GPIO15). As an output i'm getting some numbers, but they don't change when I accelerate STM32 (the difference is seen on livewatch). I'm getting strange output on RasPi even if unplug the Tx - Rx connection.
Does anyone have an idea what could be wrong?
Thank you in advance!
sudo pigpiodthenpigs mg 14 mg 15to get the modes. – joan Jan 13 '18 at 12:20