TFmini-STM32

Note: also suitable for TFmini Plus

TFmini's Example for STM32 Pi. 中文版参考 README_CN.md.

Description

This repository contains sample codes for TFmini-STM32 connection, using STM32Cube MX and Keil as development tools. It includes:

2 kinds of TFmini communication protocol: PIX and Standard Data Format(89BYTE).

3 kinds of output: switching value, CAN and I2C.

TFmini Connection

Sample codes use USART1 as communication port to connect to TFmini. Connection is as follow:

TFmini	Board
Red cable(+5V)	+5V
Green cable(TX)	PA10(RX)
Black cable(GND)	GND

TFmini Communication Code

All the samples uses USART1 to connect to TFmini, and receives data using the idle interrupt.

Steps:

1.Initialize USART1, PA8.

2.Enable USART1 Idle Interrupt.

HAL_UART_Receive_DMA(&huart1, g_usart1_rx_buf, USART_BUF_SIZE);

__HAL_UART_ENABLE_IT(&huart1, UART_IT_IDLE); //UART_IT_IDLE

3.Add Interrupt Checking to USART2_IRQHandler. Code as follow:

uint32_t tmp = 0;

if((__HAL_UART_GET_FLAG(&huart2,UART_FLAG_IDLE) != RESET))

{

 __HAL_UART_CLEAR_IDLEFLAG(&huart2);

  tmp = huart2.Instance->SR;
  tmp = huart2.Instance->DR;

  HAL_UART_DMAStop(&huart2);

  tmp =  USART_BUF_SIZE - hdma_usart2_rx.Instance->CNDTR;
  HAL_UART_Receive_DMA(&huart2, g_usart2_rx_buf, USART_BUF_SIZE);

  USART1_RX_Proc(g_usart2_rx_buf, tmp);

}

4.Add Interrupt Processing Function to Receive TFmini's Data. It only needs to use different USART1_RX_Proc to support 2 kinds of TFmini communication Protocol, and users can integrate it by themselves.

USART_2_DOUT

USART_2_DOUT is an USART-switching value sample. It does the work:

When dist > TFMINI_ACTION_DIST, PA8 is set to low level; otherwise, PA8 is set to high level.

The value of TFMINI_ACTION_DIST can be configured via Configuration Wizard of main.c.

PA8 is used to output switching value.

• Standard Data Format(89BYTE) protocol processing function:

#define TFMINI_DATA_Len 9

#define TFMINT_DATA_HEAD 0x59

void USART1_RX_Proc(uint8_t *buf, uint32_t len)

{

uint32_t i = 0;
uint8_t chk_cal = 0;
uint16_t cordist = 0;

if(TFMINI_DATA_Len == len)
{
    if((TFMINT_DATA_HEAD == buf[0]) && (TFMINT_DATA_HEAD == buf[1]))
    {
        for(i = 0; i < (TFMINI_DATA_Len - 1); i++)
        {
            chk_cal += buf[i];
        }

        if(chk_cal == buf[TFMINI_DATA_Len - 1])
        {
            cordist = buf[2] | (buf[3] << 8);

            /*cordist > TFMINI_ACTION_DIST cm, PA8 set Low;
              cordist <= TFMINI_ACTION_DIST cm, PA8 set High.*/
            if(HAL_GPIO_ReadPin(DOUT_GPIO_Port, DOUT_Pin) != GPIO_PIN_RESET)
            {
                if(cordist > TFMINI_ACTION_DIST)
                {
                    HAL_GPIO_WritePin(DOUT_GPIO_Port, DOUT_Pin, GPIO_PIN_RESET);
                }
            }
            else
            {
                if(cordist <= TFMINI_ACTION_DIST)
                {
                    HAL_GPIO_WritePin(DOUT_GPIO_Port, DOUT_Pin, GPIO_PIN_SET);
                }
            }
        }
    }
}

}

• PIX protocol processing function:

#define TFMINI_PIX_FLAG_END 0x0D0A /*\r\n*/

#define TFMINI_PIX_FLAG_NEG 0x2D /* - */

#define TFMINI_PIX_FLAG_DECPIONT 0x2E /* . */

#define ASCII_0 0x30 /*ASCII:0*/

void USART1_RX_Proc(uint8_t *buf, uint32_t len)

{

uint16_t cordist = 0;

/*xxx.xx\r\n*/
if((TFMINI_PIX_FLAG_END == (buf[len - 1] | (buf[len - 2] << 8))) \
    && (TFMINI_PIX_FLAG_DECPIONT == buf[len - 5]))
{

    if(buf[0] == TFMINI_PIX_FLAG_NEG)   /*Negative, the amplitude value too low.*/
    {
        cordist = 1200;
    }
    else
    {
        cordist = ((buf[len - 6] - ASCII_0) * 100) + ((buf[len - 4] - ASCII_0) * 10) + (buf[len - 3] - ASCII_0);
        cordist+= (len == 7) ? ((buf[len - 7] - ASCII_0) * 1000) : 0;
    }

    /*cordist > TFMINI_ACTION_DIST cm, PA8 set Low;
      cordist <= TFMINI_ACTION_DIST cm, PA8 set High.*/
    if(HAL_GPIO_ReadPin(DOUT_GPIO_Port, DOUT_Pin) != GPIO_PIN_RESET)
    {
        if(cordist > TFMINI_ACTION_DIST)
        {
            HAL_GPIO_WritePin(DOUT_GPIO_Port, DOUT_Pin, GPIO_PIN_RESET);
        }
    }
    else
    {
        if(cordist <= TFMINI_ACTION_DIST)
        {
            HAL_GPIO_WritePin(DOUT_GPIO_Port, DOUT_Pin, GPIO_PIN_SET);
        }
    }
}

}