FTDI USB to Serial Adaptor Breakout Board
If you need to program a board or chip using serial data, these small and neat boards are ideal, with their wide range of connections and changeable voltage options.
Some chips need 3.3v and can be damaged by 5v so just swap the jumper over to choose the right voltage setting.
When you connect to a PC the board will appear as a virtual COM port in the device manager.
To test that the board is working, simply join the RX and TX pins together and open the Arduino serial monitor (or other serial monitor on your computer). As you type and send text, it should be relayed straight back and appear in the monitor window.
The board is supplied with 6 right angled header pins which can plug into a breadboard, fit into stripboard or a pcb or can be connected with the female end of a Dupont lead.
DTR | RX | TX | Vcc | CTS | Gnd
Down each side are solder pads for more header pins.
Power enable | Sleep | 3.3v | 5v | Rxl | Txl | Gnd
DCD | RSD | Gnd | Rxd | Vcc | RTS | DTR | Txd
The board gets its power from the USB connection. It has pins to supply 3.3v or 5v to whatever it is being used to program.
The standard connection method is to connect RX to TX on the other board and TX to RX.
The ground connection needs to be common as well.
The receiving chip/board needs to be in programming mode if a new program/sketch is being uploaded. For this it will need a Reset and for some boards may need other connections too.
For example, the ESP8266 needs to be reset with GPIO connected to ground and there are various methods of wiring this (see our other info pages and videos).
For a home made Arduino style circuit (eg on a breadboard, these are the connections:
DTR to reset (Pin 1) via a 0.1 uF capacitor
RXD to TXD (Pin 3)
TXD to RXD (Pin 2)
VCC to regulated supply voltage
GND to GND (eg Pin 8)
CTS to GND