RS232 Bricklet 2.0


  • Sends and receives serial data
  • Provides RS-232 and UART-TTL interface
  • Configurable baudrate, parity, stop bits, word length and flow control


The RS232 Bricklet 2.0 can be used to extend the features of Bricks by the capability to send and receive serial data with RS-232 and 3.3V TTL signal level to communicate with other serial devices.

This Bricklet ist not galvanically isolated to the Tinkerforge system. This means that there is a direct electrical connection between the terminals of the Bricklet and the rest of the system. Dependent of the application this can lead to undesired connections, ground loops or short circuits. These problems can be prevented by using the Bricklet together with a Isolator Bricklet.

Technical Specifications

Property Value
Current Consumption 47mW (9.4mA at 5V, idle)
Baudrate 100 - 2000000baud
Parity none / odd / even
Stop bits 1 / 2
Word length 5 / 6 / 7 / 8
Flow control Software / Hardware / none
Dimensions (W x D x H) 45 x 35 x 17mm (1.77 x 1.38 x 0.67")
Weight 20g



The RS232 Bricklet 2.0 provides three different ways to connect to other serial devices: classic D-Sub 9 (male) connector, 5-way terminal block or 5-way pin header. But only one of these connectors can be used at the same time.

RS232 Bricklet 2.0 pinout

D-Sub 9 Connector

The D-Sub 9 (male) connector uses the RS-232 signal level. To use this connector the RX1 and RX2 pins on the pin header have to be connected by a jumper.

The connector uses the following part of standard RS-232 pinout:

Pin Function  
2 Received data RX
3 Transmitted data TX
5 Ground GND
7 Request to send RTS
8 Clear to send CTS

Terminal Block

The 5-way terminal block provides the same five RS-232 signals (RX, TX, RTS, CTS and GND) as the D-Sub 9 connector with the same RS-232 signal level. To use this connector the RX1 and RX2 pins on the pin header have to be connected by a jumper.

Pin Header

The 5-way pin header provides the received data (RX1) and transmitted data (TX) signals with 3.3V TTL signal level as well as 3.3V and GND. It does not provide RTS and CTS. To use this connector the jumper connecting the RX1 and RX2 pins has to be removed. The jumper can be stored sideways on the RX2 pin.

Test your RS232 Bricklet 2.0

To test a RS232 Bricklet 2.0 you need to have Brick Daemon and Brick Viewer installed. Brick Daemon acts as a proxy between the USB interface of the Bricks and the API bindings. Brick Viewer connects to Brick Daemon. It helps to figure out basic information about the connected Bricks and Bricklets and allows to test them.

Connect the RS232 Bricklet 2.0 to a Brick with a Bricklet Cable. Connect the RX1 and TX pins with a jumper to make the Bricklet read back its own output.

If you connect the Brick to the PC over USB, you should see a new tab named "RS232 Bricklet 2.0" in the Brick Viewer after a moment. Select this tab. If everything went as expected you can now type some text into the input editbox and hit enter. The same text should then show up in the textarea above.

RS232 Bricklet 2.0 in Brick Viewer

After this test you can go on with writing your own application. See the Programming Interface section for the API of the RS232 Bricklet 2.0 and examples in different programming languages.


A laser-cut case for the RS232 Bricklet 2.0 is available.

Case for RS232 Bricklet 2.0

The assembly is easiest if you follow the following steps:

  • Screw spacers to the Bricklet,
  • screw bottom plate to bottom spacers,
  • build up side plates,
  • plug side plates into bottom plate and
  • screw top plate to top spacers.

Below you can see an exploded assembly drawing of the RS232 Bricklet 2.0 case:

Exploded assembly drawing for RS232 Bricklet 2.0

Hint: There is a protective film on both sides of the plates, you have to remove it before assembly.

Programming Interface

See Programming Interface for a detailed description.

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