Последние публикации Мастерская электронщика

Подкаст по текущему статусу нейроинтерфейсов. На английском. Создан на основе репорта по последним решениям в области нейроинтерфейсов. Сделал чтобы послушать в дороге

# 🔧 C/C++ Pointers & Functions Cheatsheet ## Basic Pointer Syntax | Operation | Syntax | Description | |---|---|---| | Declare pointer | int* ptr; | Pointer to int | | Get address of variable | ptr = &variable; | Store address | | Dereference pointer | int value = *ptr; | Get value at address | | Access struct member | ptr->member | Same as (*ptr).member | ## Function Parameter Types ### 📋 Declaration Examples // Three different ways to pass data: void funcByValue(measurement_data_t data); // Pass copy (slow for large structs) void funcByPointer(measurement_data_t* data); // Pass address void funcByReference(measurement_data_t& data); // Pass reference (C++ only) ### 📋 Implementation Examples void funcByValue(measurement_data_t data) { data.current_cycle_index = 5; // Modifies copy, not original } void funcByPointer(measurement_data_t* data) { data->current_cycle_index = 5; // Modifies original (use ->) } void funcByReference(measurement_data_t& data) { data.current_cycle_index = 5; // Modifies original (use .) } ## How to Call Functions ### 🎯 If you HAVE a variable: measurement_data_t myData; funcByValue(myData); // Pass variable directly funcByPointer(&myData); // Pass ADDRESS with & funcByReference(myData); // Pass variable directly ### 🎯 If you HAVE a pointer: measurement_data_t* myPtr = &myData; funcByValue(*myPtr); // DEREFERENCE with * funcByPointer(myPtr); // Pass pointer directly funcByReference(*myPtr); // DEREFERENCE with * --- ## FreeRTOS Task Parameters ### 📋 Task Function Signature void taskFunction(void* parameter) { // parameter is ALWAYS a void pointer // Must cast to your actual type } ### 📋 Common Pattern // 1. Create task with data address measurement_data_t myData; xTaskCreate(taskFunc, "Task", 2048, &myData, 1, NULL); // Pass &myData // 2. In task function, cast back void taskFunc(void* parameter) { measurement_data_t* data = (measurement_data_t*)parameter; // Cast // Now you have a pointer, so: data->current_cycle_index++; // Use -> for struct members funcByPointer(data); // Pass pointer directly funcByReference(*data); // Dereference first funcByValue(*data); // Dereference first } ## Quick Reference Table | You Have | Function Wants | How to Call | |---|---|---| | Variable myData | Value func(T data) | func(myData) | | Variable myData | Pointer func(T* data) | func(&myData) | | Variable myData | Reference func(T& data) | func(myData) | | Pointer myPtr | Value func(T data) | func(*myPtr) | | Pointer myPtr | Pointer func(T* data) | func(myPtr) | | Pointer myPtr | Reference func(T& data) | func(*myPtr) | --- ## Common Mistakes & Fixes ### ❌ Wrong: Signature Mismatch // Header declares pointer: void send(measurement_data_t* data); // Implementation uses reference: void send(measurement_data_t& data) { } // LINKER ERROR! ### ✅ Fixed: Match Signatures // Both use pointer: void send(measurement_data_t* data); // Header void send(measurement_data_t* data) { } // Implementation ### ❌ Wrong: Calling Mismatch measurement_data_t* ptr = &myData; send(ptr); // If send() expects reference, this fails! ### ✅ Fixed: Dereference When Needed measurement_data_t* ptr = &myData; send(*ptr); // Dereference pointer to get reference --- ## Memory Cheatsheet | Syntax | What It Does | |---|---| | T variable; | Creates variable on stack | | T* ptr = &variable; | Pointer to stack variable | | T* ptr = malloc(sizeof(T)); | Allocate on heap (C) | | T* ptr = new T; | Allocate on heap (C++) | | free(ptr); | Free heap memory (C) | | delete ptr; | Free heap memory (C++) | --- ## 🚨 Golden Rules 1. Match function signatures exactly between header and implementation 2. Use `&` to get address of a variable 3. Use `*` to get value from a pointer 4. Use `->` for struct members when you have a pointer 5. Use `.` for struct members when you have a variable or reference 6. In FreeRTOS tasks, parameter is always `void*` - cast it!

Прямо сейчас я стримлю PCB-разводку — подключайтесь и смотрите вживую: ▶️ https://youtube.com/live/9gm2GLOLdvw?feature=share Буду объяснять свой процесс, отвечать на вопросы по KiCad, показывать приёмы и приёмы вдумчивого размещения, трассировки и хитростей в Pcbnew. Заходите!

Стримлю Factorio: https://www.youtube.com/live/ZKfQhFiq3yY?si=PrHqEwQNF9O5zu4u

Сделал на выходных из аккумов вот такой power bank для ноутбука.

Проблемы которые я думаю заботят владельцев apple. {Insert here} Проблемы которые их реально заботят: https://youtube.com/shorts/n6y0ttXkxyk?si=RhOUyg0PKe_FDUdZ

Беспилотные поезда в Австралии с 2019 года катаются!