RS485 STM32 Learning Development Board

A dedicated learning development board built around the STM32F103VET6 ARM Cortex-M3 microcontroller, with integrated RS485 interface using the industry-standard MAX485 transceiver. Physical attributes: 72 mm × 45 mm × 12 mm size, 28 g weight, 1.6 mm FR-4 substrate. Powered from 5 V input with onboard 3.3 V LDO regulation. Memory resources: 512 KB Flash, 64 KB RAM. Full peripheral access via 2.54 mm headers: GPIO banks A–E, 3× USART, 2× SPI, 2× I2C, 16-channel 12-bit ADC, and 4× general-purpose timers. RS485 side features screw-terminal connection, direction-control LED, and fail-safe bias resistors. Component selection follows industrial best practices: Yageo/Xicon passives, NDK crystal, ON Semiconductor transceivers — all sourced from authorised distributors to prevent counterfeit risk. Assembly complies with IPC-A-610 Class 2 standards. Debug interface: SWD pinout matches ST-Link v2.1 pin alignment for seamless probe connection. Real-world deployment evidence includes: restoring HMI communication in packaging line HMIs after 12+ years of service; enabling OBD-II extension modules in classic Land Rover diagnostics; and powering distributed soil-moisture monitoring in UK allotments using daisy-chained RS485 nodes — all relying on the board’s predictable timing, low-power sleep modes (