The is a compact MAX3232 RS232 to TTL level converter module commonly used in DIY electronics to bridge communication between standard computer serial ports and microcontrollers like Arduino or ESP8266. Key Technical Specifications
The HW-044 is a MAX3232-based converter module designed to interface RS232 signals with TTL levels (3.3V-5V) for microcontroller communication. It is commonly applied in serial communication tasks, including firmware flashing and device upgrades. For technical specifications, see the documentation at Amazon . hw-044 datasheet
by mistake. If your communication isn't working, try swapping the lines on your DB9 connector. Arduino Forum wiring diagram for connecting this to an ESP32? ESP32 RS232 Communication - Programming - Arduino Forum 23 Jun 2025 — The is a compact MAX3232 RS232 to TTL