Měření teploty Raspberry Pi Pico 3 — OLED displej SSD1306

/*
 teplota3.c
 * (c) Jirka Chráska 2024, All rights reserved.
 * BSD 3 clause licence
 */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include "pico/stdlib.h"
#include "hardware/i2c.h"
#include "hardware/adc.h"

// pro OLED displej
#include "ssd1306.h"
#include "font_spleen_8x5.h"
#include "font_spleen_16x8a.h"

#define DISPLAY_WIDTH 128
#define DISPLAY_HEIGHT 32
#define I2C_ADDRESS 0x3C
#define I2C_FREQ 400000
#define SLEEPTIME 55

// initializace GPIO pinů
void setup_gpios(void) {
    i2c_init(i2c_default, I2C_FREQ);
    gpio_set_function(PICO_DEFAULT_I2C_SDA_PIN, GPIO_FUNC_I2C);
    gpio_set_function(PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C);
    gpio_pull_up(PICO_DEFAULT_I2C_SDA_PIN);
    gpio_pull_up(PICO_DEFAULT_I2C_SCL_PIN);
}


int main()
{
char buffer[128];
uint16_t raw;
const float conversion_factor = 3.3f / (1<<12);
float result;
float teploty[10]={0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0};
float teplota = 0.0;
ssd1306_t disp;

    // debugování přes USB
    stdio_init_all();
    // inicializace a konfigurace 0LED displeje
    setup_gpios();
    disp.external_vcc = false;
    ssd1306_init(&disp, DISPLAY_WIDTH, DISPLAY_HEIGHT, I2C_ADDRESS, i2c_default);
    ssd1306_clear(&disp);

    // inicializace vnitřního analogově digitálního převodníku
    adc_init();
    adc_set_temp_sensor_enabled(true);
    adc_select_input(4);

    // měření teploty
    while(1) {
        for(int i=0; i<10; i++) {
	        raw = adc_read();
	        result = raw * conversion_factor;
	        teploty[i]  = 27 - (result - 0.706)/0.001721;
            sleep_ms(100);
            printf("T%d: %f ",i,teploty[i]);
        }
        teplota = 0;
        for(int j=0; j<10; j++) {
            teplota += teploty[j];
        }
        teplota /= 10.0;
        ssd1306_clear(&disp);
//        sprintf(buffer,"Vnit%cn%c teplota:", 0xf8, 0xed); (1)
//        ssd1306_draw_string_with_font(&disp,0,0,1, font_spleen_8x5, buffer);
        sprintf(buffer,"%2.1f %cC", teplota,0xb0); (2)
        ssd1306_draw_string_with_font(&disp, 0, 5, 2, font_spleen_16x8a, buffer);
        ssd1306_show(&disp);
        sleep_ms(1000);
    }
    return 0;
}

cmake_minimum_required(VERSION 3.13)

# initialize the SDK based on PICO_SDK_PATH
# note: this must happen before project()
include(pico_sdk_import.cmake)

project(teplota3)

set(CMAKE_C_STANDARD 11)

# initialize the Raspberry Pi Pico SDK
pico_sdk_init()

# rest of your project

add_executable(teplota3
	teplota3.c
	ssd1306.c
)

target_include_directories(teplota3
    PUBLIC
        ${CMAKE_CURRENT_LIST_DIR}/../
)

target_link_libraries(teplota3
    pico_stdlib
    hardware_i2c
    hardware_adc
)

pico_enable_stdio_usb(teplota3 1)
pico_enable_stdio_uart(teplota3 0)

# create map/bin/hex/uf2 file in addition to ELF.
pico_add_extra_outputs(teplota3)

# This is a copy of <PICO_SDK_PATH>/external/pico_sdk_import.cmake

# This can be dropped into an external project to help locate this SDK
# It should be include()ed prior to project()

if (DEFINED ENV{PICO_SDK_PATH} AND (NOT PICO_SDK_PATH))
    set(PICO_SDK_PATH $ENV{PICO_SDK_PATH})
    message("Using PICO_SDK_PATH from environment ('${PICO_SDK_PATH}')")
endif ()

if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT} AND (NOT PICO_SDK_FETCH_FROM_GIT))
    set(PICO_SDK_FETCH_FROM_GIT $ENV{PICO_SDK_FETCH_FROM_GIT})
    message("Using PICO_SDK_FETCH_FROM_GIT from environment ('${PICO_SDK_FETCH_FROM_GIT}')")
endif ()

if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_PATH} AND (NOT PICO_SDK_FETCH_FROM_GIT_PATH))
    set(PICO_SDK_FETCH_FROM_GIT_PATH $ENV{PICO_SDK_FETCH_FROM_GIT_PATH})
    message("Using PICO_SDK_FETCH_FROM_GIT_PATH from environment ('${PICO_SDK_FETCH_FROM_GIT_PATH}')")
endif ()

set(PICO_SDK_PATH "${PICO_SDK_PATH}" CACHE PATH "Path to the Raspberry Pi Pico SDK")
set(PICO_SDK_FETCH_FROM_GIT "${PICO_SDK_FETCH_FROM_GIT}" CACHE BOOL "Set to ON to fetch copy of SDK from git if not otherwise locatable")
set(PICO_SDK_FETCH_FROM_GIT_PATH "${PICO_SDK_FETCH_FROM_GIT_PATH}" CACHE FILEPATH "location to download SDK")

if (NOT PICO_SDK_PATH)
    if (PICO_SDK_FETCH_FROM_GIT)
        include(FetchContent)
        set(FETCHCONTENT_BASE_DIR_SAVE ${FETCHCONTENT_BASE_DIR})
        if (PICO_SDK_FETCH_FROM_GIT_PATH)
            get_filename_component(FETCHCONTENT_BASE_DIR "${PICO_SDK_FETCH_FROM_GIT_PATH}" REALPATH BASE_DIR "${CMAKE_SOURCE_DIR}")
        endif ()
        FetchContent_Declare(
                pico_sdk
                GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
                GIT_TAG master
        )
        if (NOT pico_sdk)
            message("Downloading Raspberry Pi Pico SDK")
            FetchContent_Populate(pico_sdk)
            set(PICO_SDK_PATH ${pico_sdk_SOURCE_DIR})
        endif ()
        set(FETCHCONTENT_BASE_DIR ${FETCHCONTENT_BASE_DIR_SAVE})
    else ()
        message(FATAL_ERROR
                "SDK location was not specified. Please set PICO_SDK_PATH or set PICO_SDK_FETCH_FROM_GIT to on to fetch from git."
                )
    endif ()
endif ()

get_filename_component(PICO_SDK_PATH "${PICO_SDK_PATH}" REALPATH BASE_DIR "${CMAKE_BINARY_DIR}")
if (NOT EXISTS ${PICO_SDK_PATH})
    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' not found")
endif ()

set(PICO_SDK_INIT_CMAKE_FILE ${PICO_SDK_PATH}/pico_sdk_init.cmake)
if (NOT EXISTS ${PICO_SDK_INIT_CMAKE_FILE})
    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' does not appear to contain the Raspberry Pi Pico SDK")
endif ()

set(PICO_SDK_PATH ${PICO_SDK_PATH} CACHE PATH "Path to the Raspberry Pi Pico SDK" FORCE)

include(${PICO_SDK_INIT_CMAKE_FILE})