Add example projects

This repo shows how to use the Raspberry Pi Pico SDK.

## Init submodules 

You will need the **pico-sdk** to compile the code in this repo. Use the following command to clone it with all its submodules:

```bash

git submodule update --recursive --init pico-sdk

```

## Raspberry Pi Documentation

[Raspberry Pi Pico C/C++ SDK][1]

[Raspberry Pi Pico Quick Start][2]

[Raspberry Pi Pico W (WiFi) Quick start][3]

## Projects

[SHT30 sensor](sht30/README.md): Application that acquires Humidity and Temperature values from a SHT30 sensor.

[Blinky](blinky/README.md): Application to blink a led

[PWM](pwm/README.md): Application to generate a PWM signal.

### Build 

A utility script allows to build and deploy the projects. Usage:

```bash

Build Raspberry Pi Pico projects

Syntax: ./build.sh [-b|c|d|f|h|p] <args>

[ -b ]        Build project.

[ -c ]        Clean

[ -d ]        Launch debugger

[ -f ]        Flash board

[ -h ]        Help

[ -p PATH ]   Set project path

```

Example:

```bash

./build.sh -bf -p blinky/

```

Will build and flash the blinky application on the Raspberry Pi Pico.

If you want to manually build your project checkout this [chapter](#tools).

## Add new project

If you want to add a project you will need to create a new project folder containing the following basic files.

```

new_project

|

|---.config

|---CMakeLists.txt

|---pico_sdk_import.cmake

|---main.cpp

|---...

```

The *pico_sdk_import.cmake* just need to be copied to your project folder no modification required.

### Config file

This files contains two values:

- BOARD_TYPE: Defines the type of board to which the code will be compiled for.

- SRC_PATH: Relative path to the source code

Example:

```bash

BOARD_TYPE=grove_pico_w

SRC_PATH=src

```

A list of supported boards is available [here](pico-sdk/src/boards/include/). You can also define your own

like I did for the *SHT30* app. Checkout this [file](sht30/src/grove_pico_w.h)

### Cmakelists

Here is a basic example for the Pico without WiFi:

```bash

cmake_minimum_required(VERSION 3.13)

include(pico_sdk_import.cmake)

project(blinky C CXX ASM)

set(CMAKE_C_STANDARD 11)

set(CMAKE_CXX_STANDARD 17)

list(APPEND PICO_BOARD_HEADER_DIRS ${CMAKE_CURRENT_LIST_DIR})

pico_sdk_init()

file(GLOB SRC *.cpp)

add_executable(${PROJECT_NAME} ${SRC})

pico_enable_stdio_usb(${PROJECT_NAME} 0)

pico_enable_stdio_uart(${PROJECT_NAME} 1)

target_include_directories(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_LIST_DIR})

target_link_libraries(${PROJECT_NAME} pico_stdlib)

pico_add_extra_outputs(${PROJECT_NAME})

```

## Tools

**This guide as been tested for Ubuntu 22.04**

> :warning: This command must be performed on your host machine not in a running docker container

## Projects

[SHT30 sensor](sht30/README.md)

[1]:https://datasheets.raspberrypi.com/pico/raspberry-pi-pico-c-sdk.pdf?_gl=1*155jvvo*_ga*MTk5NjQ0ODQwNy4xNzAyNjI5NzEx*_ga_22FD70LWDS*MTcwNDI5MDg1OS4zLjEuMTcwNDI5MTA0Ny4wLjAuMA..

[2]:https://datasheets.raspberrypi.com/pico/getting-started-with-pico.pdf?_gl=1*i8b34r*_ga*MTk5NjQ0ODQwNy4xNzAyNjI5NzEx*_ga_22FD70LWDS*MTcwNDI5MDg1OS4zLjEuMTcwNDI5MTEzNy4wLjAuMA..

cmake_minimum_required(VERSION 3.13)

include(pico_sdk_import.cmake)

project(blinky C CXX ASM)

set(CMAKE_C_STANDARD 11)

set(CMAKE_CXX_STANDARD 17)

list(APPEND PICO_BOARD_HEADER_DIRS ${CMAKE_CURRENT_LIST_DIR})

pico_sdk_init()

file(GLOB SRC *.cpp)

add_executable(${PROJECT_NAME} ${SRC})

pico_enable_stdio_usb(${PROJECT_NAME} 0)

pico_enable_stdio_uart(${PROJECT_NAME} 1)

target_include_directories(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_LIST_DIR})

target_link_libraries(${PROJECT_NAME} pico_stdlib)

pico_add_extra_outputs(${PROJECT_NAME})

 No newline at end of file

# Blinky

Sample application to showcase the usage of *repeating timer* to make a led blink.

## Wiring

![Hardware connection](../img/pico_debug_wiring.png)

 No newline at end of file

#include <string.h>

#include <stdio.h>

#include "pico/stdlib.h"

#define LED_DELAY_MS    250

#ifndef PICO_DEFAULT_LED_PIN

#error Blinky example requires a board with a LED

#else

#define LED_PIN     PICO_DEFAULT_LED_PIN

#endif

bool led_callback(struct repeating_timer *t)

{

    static bool value = true;

    gpio_put(LED_PIN, value);

    value = !value;

    return true;

}

int main()

{

    struct repeating_timer *timer = new struct repeating_timer;

    stdio_init_all();

    printf("Hello from blinky example\n");

    gpio_init(LED_PIN);

    gpio_set_dir(LED_PIN, GPIO_OUT);

    if(!add_repeating_timer_ms(LED_DELAY_MS, led_callback, NULL, timer)) {

        printf("Error: Failed to setup the timer");

        return 1;

    }

    while(1)

        tight_loop_contents();

    return 0;

}

 No newline at end of file