# STM32F401RE-PotholeDetector

**Repository Path**: byxlk/STM32F401RE-PotholeDetector

## Basic Information

- **Project Name**: STM32F401RE-PotholeDetector
- **Description**: Nucleo-STM32F401RE and  X-NUCLEO-IKS01A2 code about Free Fall Detection and sending though SPI
- **Primary Language**: C
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-03-27
- **Last Updated**: 2021-08-30

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# Pervasive Systems 2018 - Pothole Detector

This repository contains all information regarding the code of STM32F401RE for the Pothole Detector project.

This board is part of a [bigger](https://github.com/onaralili/pothole-detector-project) system, it will be connected to other board via I2C and it will send data through LoRa.
The code sends via I2C the events detected from LSM6DSL (x-nucleo-iks01a2) accelerometer.

Complete project can be visited [here](https://github.com/onaralili/pothole-detector-project)

## Instrucctions
This project was done using a generated code by System Workbench toolchain distributed by STMicroelectronics, you can download the pack [here](http://www.st.com/en/development-tools/sw4stm32.html) as well as eclipse IDE.

### 1. First you need to make the board connections:

<center>

<img src="https://raw.githubusercontent.com/Mickyleitor/STM32F401RE-PotholeDetector/master/Docs/Board-connections.png" width="692">

| STM32F401RE (X-NUCLEO-IKS01A2)  | Seeeduino LoRaWAN w/ GPS |
|             :---:               |          :---:           |
|         PA8 (I2C3 SCL)          |         PC5 (SCL)        |
|         PC9 (I2C3 SDA)          |         PC4 (SDA)        |
|              +5V                |           +5V            |
|              GND                |           GND            |
  
</center>

### 2. Upload the code inside the board
* The code contains all libraries used by peripherical modules but make sure you all have a working environment.
* Import the code by manualling clicking right on the Project Explorer
* Build the code and run it.
* If it fails then make sure libraries of X-NUCLEO-IKS01A2 (Drivers/BSP) dependencies are added inside project properties.

### 3. Testing board, button and LED.
You can see basic information of what's happening inside the board. 
* LED: Show status of internal functions

| Loops |            Functionality              |
| :---: |                :---:                  |
|  Inf  |  Internal error, needs manual reset   |
|   3   |        Timed mode is selected         |
|   6   |        Burst mode is selected         |

* Button: via SERCOM (using Putty, for example) you can view:

| Times button pressed within 1 s |            Functionality              |
|             :---:               |                :---:                  |
|               1                 | Print counted events and timer status |
|               2                 |    Switch between Burst/Timed mode    |
|               3                 |  Test I2C connection and send events  |

### 4. Burst / Timed Modes
* Timed mode means every detected events is stored until a timer interrupts. If Timer interrupts it's sent via I2C to Seeeduino. 
* In Burst mode there is no need to wait for the Timer IT so every detected events will be sent instantly to Seeeduino via I2C.

### 5. DEBUG Mode
You can view all basic information like detected potholes and low-level processes by uncommenting the DEBUG_MODE define in [main.c](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c) file and openning a SERIAL/USART terminal monitor.

## Finite State Machine Diagram
![Finite State Machine Diagram](https://raw.githubusercontent.com/Mickyleitor/STM32F401RE-PotholeDetector/master/Docs/State-machine.png)

STM32F401RE is configured to have several interrupts. 
- Timer ISR. It's used by Timed mode so everytime it interrupts, the stored events detected is sent via I2C if it's non-zero.
- GPIO Ext L line ISR. It's used twice by Button (GPIO C - GPIO_PIN_13) and LSM6DSL INT2 (GPIO B - GPIO_PIN_4)
- USART and I2C. It's managed internally by native libraries.

Libraries used:
- STM32F4xx_HAL_Driver. For GPIO, I2C, Timer and UART management.
- BSP. For X_NUCLEO_IKS01A2 accelerometer (x_nucleo_iks01a2_accelero).

## Workflow and methods
1. Peripherals is configured to do:
 - Timer0 interrupt every 30 second via [MX_TIM1_Init](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L303) function. When it's triggered go to StatusFlag 1.
 - USART2, I2C3 is configured via [MX_USART2_UART_Init](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L336) and [MX_I2C3_Init](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L283). 
 - [GPIO External interrupt](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L362) for GPIOC Pin 13 (built in button) and GPIOB Pin 4 (LSM6DSL INT2). Both done with BSP libraries. 
 - I2C2. For X-NUCLEO-IKS01A2 communications, it's initialized by [BSP_ACCELERO_Init](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Drivers/BSP/X_NUCLEO_IKS01A2/x_nucleo_iks01a2_accelero.c#L103).
 
2. Accelerometer is configured using [initializeAllSensors](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L418) and [enableAllSensors](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L435), internally it uses BSP_ACCELERO_XXX functions. 
3. Now X-NUCLEO-IKS01A2 has its LSM6DSL running, when more than X g's (G-forces more than a threshold) then it will call to STM32F401 via [HAL_GPIO_EXTI_Callback](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L464), notifying a new data is received via I2C2. 
4. In [HAL_GPIO_EXTI_Callback](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L464), MCU go to StatusFlag 2 if the Pin number interrupt is LSM6DSL INT2 (GPIO B - GPIO_PIN_4), otherwise StatusFlag is StatusFlag plus 3 ([See step 7](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/README.md#L82))
5. In StatusFlag 2, the data received via I2C2 is decoded and interpreted using [BSP_ACCELERO_Get_Event_Status_Ext](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L167) getting a [status flag](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L106). If status.FreeFallStatus is true, the stored events (mems_events_detected) is increased. 
In burst mode go directly to StatusFlag 1. 
6. In StatusFlag 1, if stored events (mems_events_detected) is non-zero then value is sent via I2C3 using [HAL_I2C_Master_Transmit](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L156) function.
7. In StatusFlag 3, mode between Timed or Burst can be selected pushing twice within 1 second the built-in button. Once in status 3 it waits 500 ms so if [HAL_GPIO_EXTI_Callback](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/Src/main.c#L464) is called again, StatusFlag is increased. When switch case structure reads StatusFlag then it could be 3/6/9, see [step 3](https://github.com/Mickyleitor/STM32F401RE-PotholeDetector/blob/master/README.md#L42) for number interpretation.

## Credits

Michele La Malva Moreno - [LinkedIn](https://www.linkedin.com/in/michele-la-malva-moreno/) | [Blogspot](https://mickysim.blogspot.com/) | [Github](https://github.com/Mickyleitor)