RS232 Shield


RS232 Shield is a standard communication port for industry equipment.This module is base on MAX232,which is a dual driver/receiver that includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels from a single 5-V supply. The shield integrates DB9 connectors (female) that provide connection to various devices with RS232 interface. Also the RS232 headers will facilitate your connections and commissioning. It provides the welding areas to make full use of extra space on it, which is highly convenient for prototyping.


  • Meets or Exceeds TIA/EIA-232-F and ITU
  • Operates Up To 120 kbit/s
  • Low Supply Current
  • LED Indicator
  • DB9 Connectors(female)
  • Welding Areas

Interface Function


First,we can test it by computer.

Hardware Installation

  1. Seeeduino v3.0,Mini usb Cable,RS232 Shield,RS232 to USB Cable.
  2. Make the connections as below. The jumper hats can be used to select the software serial port from the digital pins. You can set them to D7(232_TX) and D6(232_RX), and modify the code to “SoftwareSerial mySerial(7, 6); // 232_TX, 232_RX

Software Part

  • 1) Open Arduino IDE, and paste the code below.
#include <SoftwareSerial.h>
SoftwareSerial mySerial(7, 6); //232_TX,232_RX
void setup()
    // Open serial communications and wait for port to open:
    while (!Serial) {
        ; // wait for serial port to connect. Needed for Leonardo only
    Serial.println("Goodnight moon!");
    // set the data rate for the SoftwareSerial port
    mySerial.println("Hello, world?");
void loop() // run over and over
    if (mySerial.available())
    if (Serial.available())
  • 2) Upload the code. Note that you should select the correct board type and COM port.
  • 3) Open the Serial Monitor.

You can see :


Help us make it better

Thank you for choosing Seeed. A couple of months ago we initiated a project to improve our documentation system. What you are looking at now is the first edition of the new documentation system. Comparing to the old one, here is the progresses that we made:

  • Replaced the old documentation system with a new one that was developed from Mkdocs, a more widely used and cooler tool to develop documentation system.
  • Integrated the documentation system with our official website, now you can go to Bazaar and other section like Forum and Community more conveniently.
  • Reviewed and rewrote documents for hundreds of products for the system’s first edition, and will continue migrate documents from old wiki to the new one.

An easy-to-use instruction is as important as the product itself. We are expecting this new system will improve your experience when using Seeed’s products. However since this is the first edition, there are still many things need to improve, if you have any suggestions or findings, you are most welcome to submit the amended version as our contributor or give us suggestions in the survey below, Please don’t forget to leave your email address so that we can reply.

Happy hacking