RS232 to TTL Converter Module
This board converts RS232 to TTL and vice versa (TX and RX). Operating voltage is 3.3V-5V. This module is based on MAX3232, which is a dual driver/receiver that includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels. The module will allow a microcontroller to communicate with an industrial computer. The DB9-connector is female (DCE).
More information is available on the website of Seeed Studio and wiki.