The FT232RL USB to TTL 3.3V 5.5V Serial Adapter Module for Arduino is a basic breakout board for the FTDI FT232RL USB to serial IC, Revision 2. The pinout of this board matches the FTDI cable to work with official Arduino and cloned 5V Arduino boards. It can also be used for general serial applications.

The major difference with this board is that it brings out the DTR pin as opposed to the RTS pin of the FTDI cable. The DTR pin allows an Arduino target to auto-reset when a new Sketch is downloaded. This is a really nice feature to have and allows a sketch to be downloaded without having to hit the reset button. This board will auto reset any Arduino board that has the reset pin brought out to a 6-pin connector.
 

The pins labelled BLK and GRN correspond to the coloured wires on the FTDI cable. The black wire on the FTDI cable is GND, green is CTS. Use these BLK and GRN pins to align the FTDI basic board with your Arduino target.
 

This board has TX and RX LEDs that make it a bit better to use over the FTDI cable. You can actually see serial traffic on the LEDs to verify if the board is working.
 

This board was designed to decrease the cost of Arduino development and increase ease of use (the auto-reset feature rocks!). Our Arduino Pro boards and LilyPads use this type of connector.
 

One of the nice features of this board is a jumper on the back of the board that allows the board to be configured to either 3.3V or 5V (both power output and IO level). This board ship default to 5V, but you can cut the default trace and add a solder jumper if you need to switch to 3.3V.
 

How to interface with the Pro Mini Module:
 

• FTDI—–>Pro Mini
   
• GND—->GND
   
• VCC—->VCC
• TX—–> RX
• RX—-> TX
• DTR—->GRN

Features of FT232RL IC:-

• Single chip USB to asynchronous serial data transfer interface.
   
• Entire USB protocol handled on the chip. No USB specific firmware programming required.
• Fully integrated 1024 bit EEPROM storing device descriptors and CBUS I/O configuration.
• Fully integrated USB termination resistors.
• Fully integrated clock generation with no external crystal required plus optional clock output selection enabling a glue-less interface to external MCU or FPGA.
• Data transfer rates from 300 baud to 3 Mbaud (RS422, RS485, RS232) at TTL levels.
• 128 byte receive buffer and 256 byte transmit buffer utilising buffer smoothing technology to allow for high data throughput.

Features of FT232RL USB TO TTL Module:-
 

• Material: PCB + Electronic Component
   
• Support 3.3V, 5V
• Main Color: Red
• Chipset: FT232RL
• USB power has over current protection, using 500MA self-restore fuse
• RXD/TXD transceiver communication indicator
• Pin definition: DTR,RXD,TX,VCC,CTS,GND
• Pitch:2.54mm
• Module Size: About 36mm(length)*17.5mm(width)
   
• Interface : Mini USB