Usage Example for Arduino-USB to TTL Conversion

Hardware Preparation

• DFR0216 DFRduino UNO R3 x 1
• FIT0056 USB Cable A-B for Arduino x 1
• FIT0265 Micro USB Cable x 1
• TEL0070 Multi USB / RS232 / RS485 / TTL Converter x 1
• Arduino Jumper Cables x 1

Software Preparation

• Download Arduino IDE: Click to download Arduino IDE
• Driver Installation:
  • V1.0 uses FT232R USB to TTL chip, please click here to download Driver.
  • V2.0 uses CH340 USB to TTL chip, please click here to download Driver
    Note: CH340 driver is free to install for most of Windows OS, if you find there is no COM Port in Device Manager, please download the driver and install it.

Wiring Diagram

According to the following connection diagram，connect it.
Plugin the A to B USB to UNO.

Sample Code

void setup()
{
  Serial.begin(115200);
}
void loop()
{
  if(Serial.available()){
  Serial.write(Serial.read());
  }
}

Result

We need a serial monitor for monitoring data. There're lots of good tools like putty,CoolTerm and so on.In this case, we choose CoolTerm to do this.

Please set the baud rate to 115200 bps and com port.Back to the main interface, click Connection--Send String, the following dialog will open.

You can send the string in this dialog. The string received can be showed in the other port(UNO port).

Thus far，you achieve the function USB to TTL.
However, you can test reversed converter based on this function, being B to A converter. You only need to change the UNO code. You will see the change that coolterm will receive data from UNO.

Refer to the test code：

void setup()
{
  Serial.begin(115200);
}
void loop()
{
  Serial.print("Hello,DFRobot！");
  Serial.println();
  delay(500);
}

Other Reference Connection

1.TTL to 232 converter

2.USB to 485 converter