Guide

Summary: ESP32 Pinout in 30 Seconds The ESP32 is Espressif’s dual-core Xtensa LX6 MCU running at up to 240 MHz with Wi-Fi and Bluetooth. The chip has 34 GPIOs; boards break out either 30 or 38 pins. The 30 vs 38 pin difference is not just pin count: six of the extra pins on the 38-pin board are wired to the internal flash and cannot be used. GPIO6 through GPIO11 belong to the flash chip. Connect anything there and the board will not boot. GPIO34, 35, 36 and 39 are input only. They cannot drive an output and have no internal pull-up or pull-down. GPIO0, 2, 5, 12 and 15 are strapping pins. Hold one at the wrong level during boot and the board either refuses to start or hangs in flashing mode. ADC2 does not work while Wi-Fi is on. Wire analog sensors to the ADC1 pins, GPIO32 to GPIO39. The board runs on 3.3 V logic and is not 5 V tolerant. Never wire a 5 V sensor output straight to a GPIO. The ESP32 is cheap, fast, and ships with Wi-Fi and Bluetooth built in. It also has one habit that drives beginners up the wall: the board says 38 pins, and you cannot use all of them. Wire a relay to one pin and the board stops booting. Wire a sensor to another and the reading turns to noise the moment Wi-Fi comes up. Wire an LED to a third and it flickers once on every reset. ...

Summary: ESP32-S3 in 30 Seconds ESP32-S3 is Espressif’s dual-core Xtensa LX7 MCU running at 240 MHz with Wi-Fi and Bluetooth 5 (LE). 45 GPIOs, 512 KB of SRAM. Three things set it apart from the classic ESP32: built-in USB OTG, 14 touch channels, and a vector instruction set for neural-network workloads. Codes like N8R8 and N16R8 on the board are not arbitrary: N = flash, R = PSRAM, numbers in megabytes. The board has two USB ports and they behave differently. This is where beginners get stuck. GPIO35, GPIO36 and GPIO37 are unusable on many variants, GPIO19 and GPIO20 belong to USB, and four pins do double duty as strapping pins. Depending on the board revision, the RGB LED sits on either GPIO48 or GPIO38. If your blink sketch does nothing, check that first. If you have built something with an ESP32 and then tried to add a camera, audio, or a color display, you have probably hit the wall: not enough pins, not enough RAM, no USB. ...

Running Claude Code against a non-Claude model works, and you do it on a path the providers document themselves rather than through a hack. Ollama, Moonshot and Z.ai all publish an Anthropic-compatible endpoint. Setup comes down to three environment variables. This guide covers the steps for all three providers, how to make the configuration stick, and the errors people hit most 🔌 The Short Answer Three providers, three addresses Provider ANTHROPIC_BASE_URL Ollama (local) http://localhost:11434 Moonshot / Kimi https://api.moonshot.ai/anthropic Z.ai / GLM https://api.z.ai/api/anthropic MiniMax https://api.minimax.io/anthropic Alibaba / Qwen depends on the plan Add ANTHROPIC_AUTH_TOKEN and a model name and that’s the whole setup. ...

Claude Code isn’t a chat window in your browser. It opens in your terminal, reads your project’s files on its own, edits them, runs the tests and commits. Say “fix that bug” and the expectation is that it finds the file and changes it. This guide walks the path from install to your first code change, and gives a straight answer on the free-version question 🧑‍💻 The Short Answer If you only have a minute Install (Windows PowerShell): irm https://claude.ai/install.ps1 | iex Install (macOS, Linux, WSL): curl -fsSL https://claude.ai/install.sh | bash Start it: cd into your project and type claude No free tier: you need a Claude subscription (Pro, Max, Team, Enterprise) or a prepaid Console account First move: run /init to generate a CLAUDE.md for the project What Is Claude Code? Claude Code is Anthropic’s coding agent for the terminal. What separates it from a regular AI assistant is that it doesn’t only produce text. It has tools for reading files, writing files, running commands and searching the web, and it decides on its own which to use and in what order. ...

Adafruit GFX is the layer nearly every Arduino display library sits on top of. Adafruit_SSD1306, Adafruit_ILI9341, Adafruit_ST7735, the e-paper libraries and dozens of third party drivers all inherit from it, which is why the same drawLine call works on a 128x64 monochrome OLED and on a 320x240 colour TFT. The catch is that the drawing functions live in the base class while the colours, the constructor and the buffer behaviour come from the driver. That split is where most of the confusion comes from. This guide covers the whole API in one place. ...