on your MCU, and vice versa. If you get no data, try swapping these two pins first. Hardware vs. Software Serial : If you are using an Arduino Uno, use the SoftwareSerial
To avoid confusion, you should:
What battery are you planning to charge? hw-044 datasheet
Features a DB9 female connector (typically wired as DCE) for the RS232 side and header pins (VCC, GND, TXD, RXD) for the TTL side.
If you are building a project that requires precise control—like adjusting the volume on a custom speaker, navigating a menu on an LCD screen, or controlling the brightness of an LED—you have likely come across the . on your MCU, and vice versa
Converts high-voltage RS232 levels to logic levels and vice versa.
Cheap HW-044 modules often use "clone" MAX3232 chips which may struggle with higher baud rates or exhibit instability at exactly 3.0V. If you are planning a build, I can help you with: Software Serial : If you are using an
: If you are using a 3.3V microcontroller, ensure the VCC pin is connected to 3.3V. Providing 5V to the module while connected to a 3.3V MCU can damage your processor's RX pin.
