MyFi is a breakout board for the FTDI FT232RL which is a USB to Serial bridge IC. It has four signal lines and two lines for providing power supply. It works on two voltage logic levels namely +3.3V and +5V. The four signal lines are RX, TX, RTS/DTR and CTS. There are three LEDs on the board – a power on LED and TX and RX signal indicators that blink during data transmission / reception.


  • Board Description
  • Key Features
  • Driver Installation Guide
  • Useful Downloads

Board Description

The UART signals and power supply lines on the MyFi is brought out on a 6-pin female headers with 0.1″ spacing. The connector pinout is compatible with FT232 breakout boards made by SparkFun and several other manufacturers. The supply voltage as well as the logic voltage levels can be selected by means of solder shorted jumpers on the bottom side of the board. The user has a choice of independently selecting 3.3V or 5V for both supply as well as IO voltages. Further, one of the handshaking signals RTS and DTR can be routed to the 6-pin connector using solder shorted jumper selections as well.In case of Arduino Uno like boards, the MyFi can be used to program the target board as well as communicate by UART for Serial Monitor. The DTR pin is used to auto-reset the target board while uploading sketch/HEX code.RTS pin is an output and CTS pin is an input. RTS pin should be connected to the CTS pin of the target device and CTS should be connected to RTS of the target when handshaking signals are required (particularly useful for high speed communications).

Key Features

  • Single chip USB to asynchronous serial data transfer interface.
  • UART interface support for 7 or 8 data bits, 1 or 2 stop bits and odd / even / mark / space / no parity.
  • Fully assisted hardware or X-On / X-Off software handshaking.
  • Data transfer rates from 300 baud to 3 Megabaud (TTL levels) and 300 baud to 1 Megabaud (RS232).
  • Transmit and receive LED drive signals.
  • Device supplied preprogrammed with unique USB serial number.
  • Integrated 3.3V level converter for USB I/O .
  • USB 2.0 Full Speed compatible.

Driver Installation Guide

The MyFi board does not require any additional driver installations when used on Mac as well as Linux based operating systems (such as Ubuntu, Debian etc). However, a device driver software installation is required on Windows based machines. The drivers for MyFi can be downloaded directly from the FTDI Website. The driver files also come as a part of the standard Arduino IDE installation.However, due to digital signature issues with Windows 8 and higher operating systems, the driver installation will not succeed automatically. The following steps need to be followed in order to install the driver on Windows 8+ machines.


Useful Downloads

  • FT232 Drivers
  • PuTTY
  • RealTerm