The RS232 to TTL Serial Interface Module is a board with the MAX3232 transceiver integrated circuit (IC). It facilitates serial communication between TTL and RS232 ports by providing the necessary electrical signal conversion.
It comes with a DB9 connector soldered at one end, and four header pins at the other end. The DB9 connects directly to a COM port of a computer.
It has a maximum guaranteed data rate of 120 kbps, and the circuitry requires four 0.1µF charge-pump support capacitors.
These boards connect to systems with a UART hence, they work with most microcontrollers.