TangoDOS

Overview

TangoDOS is a DOS-inspired automation firmware for the Raspberry Pi Pico 2W (RP2350). It provides a familiar command-line interface over USB serial, a built-in HTTP web server for browser-based control, and a powerful scripting system — all running on a microcontroller that costs less than ₹600.

Users write automation scripts in a SCHEDULE.BAT file — a plain text file stored on the Pico's internal flash (LittleFS). Scripts can control GPIO pins, read ADC inputs, trigger I2C and SPI devices, send UDP messages, and execute scheduled tasks based on exact time, day-of-week, sunrise, or sunset — with full holiday awareness. Everything is configurable via a CONFIG.TXT file; no recompilation needed.

TangoDOS runs dual-core on the RP2350: Core 0 handles the command interpreter, HTTP server, and scheduler; Core 1 handles background tasks including non-blocking delays, PWM generation, and blink patterns. Inter-core communication uses the Pico SDK queue primitives for thread-safe message passing.

Key Features

• DOS-like CLI over USB serial (115200 baud) — familiar to engineers
• Built-in HTTP web server — browser control from any device on the network
• SCHEDULE.BAT scripting — plain text, no compiler needed
• Scheduling: exact time, recurring weekly, sunrise/sunset, holiday-aware
• GPIO, ADC, PWM, I2C, SPI, UART — all accessible via simple commands
• 50 user variables (float and string) with arithmetic and expressions
• OTA firmware updates — no USB cable needed for updates
• WiFi station or AP mode — works standalone or on existing network
• NTP time sync — pool.ntp.org, Google, Cloudflare, NIST
• DS3231 RTC support — accurate timekeeping without network

Example Script (SCHEDULE.BAT)

REM -- Morning lights on at sunrise, off at 10 PM
atsunrise +5 pin set GPIO4 high
onweekdays mon,tue,wed,thu,fri 22:00:00 pin set GPIO4 low

REM -- Log temperature every 10 minutes
ontime+ 0h 10m 0s adc read GPIO26
ontime+ 0h 10m 0s print %adc_value%

Specifications