--- title: "tinybasic" url: "https://maker.wiznet.io/TheoIm/projects/tinybasic/" markdown_url: "https://maker.wiznet.io/TheoIm/projects/tinybasic/md" type: "UCC: User Created Content" author: "Stefan" author_url: "https://github.com/slviajero/tinybasic" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "Stefan" original_url: "https://github.com/slviajero/tinybasic" published: "2025-12-02" language: "en" likes: 0 views: 372 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # tinybasic > TinyBasic is a lightweight BASIC interpreter for MCU, enabling instant script-based control without recompiling firmware, with GPIO, files, display, and network Original author: Stefan (source: https://github.com/slviajero/tinybasic) ## Article TinyBasic is a **lightweight BASIC interpreter and runtime environment designed to run directly on microcontrollers (MCUs)**. It allows users to write, modify, and execute control logic instantly—without recompiling or re-uploading firmware. While preserving classic BASIC syntax, TinyBasic extends it with modern MCU features such as GPIO control, filesystems, displays, MQTT networking, and Ethernet connectivity. At its core, TinyBasic transforms an MCU from a static firmware target into an **interactive, script-driven runtime system**. --- ## What Problem Does TinyBasic Solve? [Embedded media](https://www.youtube.com/embed/JO9eyPt0NQc) Traditional MCU development follows a rigid loop: Edit C/C++ source code Compile Flash firmware Reboot Test TinyBasic removes this cycle. With TinyBasic, developers can: Enter BASIC code directly on the device Execute logic immediately Adjust behavior in real time Persist programs without reflashing firmware This makes TinyBasic especially suitable for **education, rapid prototyping, device control, and interactive IoT systems**. --- ## System Architecture ```plaintext BASIC Program (.bas user scripts) PRINT, INPUT, OPEN, IF, FOR, NETSTAT │ ▼ TinyBasic Interpreter Core - Token parser - Execution loop - Variable and array management - Expression evaluator │ ▼ Runtime / Hardware Abstraction Layer (C/C++ compiled firmware) - GPIO / ADC / Delay - Display / Keyboard - Filesystem (SD / EEPROM / LittleFS) - Network (MQTT / TCP/IP) │ ▼ MCU + Peripheral Hardware AVR / ESP32 / RP2040 / SAMD / ARM Ethernet / Wi-Fi / VGA / SD / PS2 ``` In this design, BASIC programs never access hardware directly. All hardware interaction is abstracted through a precompiled runtime layer. --- ## Why TinyBasic Is Suitable for Real-Time Control ### Deterministic Execution Model TinyBasic is explicitly designed to behave predictably: No garbage collection Variables and strings remain in fixed memory locations No runtime memory relocation This guarantees consistent execution timing, making TinyBasic suitable for **real-time and control-oriented applications**. --- ### Compile-Time Feature Binding Platform capabilities are defined at compile time using configuration headers such as `hardware-arduino.h`. ```c #define ARDUINOEEPROM #define ARDUINOSD #define ARDUINOMQTT #define ARDUINOTFT #define ARDUINOETH ``` These switches determine: Which libraries are included Which BASIC commands are available Which hardware resources the runtime can access BASIC scripts cannot alter this configuration, ensuring **system stability and reproducibility**. --- ## Networking and MQTT Model TinyBasic treats networking as a **stream**, equivalent to serial ports or files. ```plaintext BASIC Program │ PRINT / INPUT / OPEN ▼ TinyBasic Stream Interface ▼ Network Stack ├─ Ethernet.h → WIZnet W5100 / W5500 └─ WiFi.h → ESP8266 / ESP32 ``` From the BASIC programmer’s perspective, networking requires no knowledge of sockets, TCP/IP, or MQTT internals. Communication is handled entirely through `OPEN`, `PRINT`, `INPUT`, and `NETSTAT`. --- ## Ethernet and WIZnet Perspective Architecturally, TinyBasic aligns well with **WIZnet Ethernet controllers**. Stream-oriented I/O model Hardware TCP/IP offloading reduces MCU load Stable, deterministic wired communication Natural fit for MQTT-style messaging The runtime accesses Ethernet through the standard Arduino Ethernet library, which supports **WIZnet W5100 and W5500** devices. While TinyBasic does not hardcode a specific chip, its design fully benefits from WIZnet’s hardware TCP/IP approach. ```plaintext TinyBasic Runtime ↓ Ethernet.h ↓ WIZnet W5100 / W5500 ``` --- ## Example: MQTT-Based Sensor Publishing ```plaintext 10 REM Simple MQTT writer 20 AP = AZERO 100 OPEN &9, "iotbasic/data", 1 200 FOR I 210 A$ = "analog:" + STR(AREAD(AP)) 220 PRINT &9, A$ 230 IF NETSTAT<>3 THEN PRINT "No connection" 240 DELAY 3000 250 NEXT ``` This BASIC program reads an analog input, converts it to text, and publishes it over MQTT—without compiling or flashing new firmware. --- ## Standalone TinyBasic Computer TinyBasic can scale beyond embedded control into a **fully standalone computer**. Typical configurations include: ESP32 VGA output (FabGL) PS/2 keyboard SD card storage Audio output ### Boot Model ```plaintext Power ON ↓ TinyBasic Interpreter Start ↓ autorun.bas executed (if present) ↓ User interaction or autonomous logic ``` All coding, execution, and storage can be performed **without a connected PC**. --- ## Limitations No MQTT TLS or authentication Network configuration fixed in C code Polling-based I/O model Not suitable for high-throughput data transfer These trade-offs are intentional and consistent with TinyBasic’s deterministic design goals. --- ## Key Takeaway TinyBasic is **not just a retro BASIC interpreter**. It is a **lightweight, deterministic runtime environment for microcontrollers**, enabling instant execution of control logic, interactive IoT behavior, and standalone embedded systems. **TinyBasic turns an MCU into a programmable, interactive runtime platform.** --- ## Original Source GitHub: Manual: Wiki: --- Source: https://maker.wiznet.io/TheoIm/projects/tinybasic/