After releasing the 2.5kV Isolated DMX Shield for sale (which might not be that attractive to hobbyist because of the price) I have released a simple MAX485 based DMX RDM shield as well. You can buy the DMX Shield for Arduino on Ebay or visit my store on Ebay.
On the shield you can use the jumpers to select whether you would like to connect your Receive and Transmit to the RX and TX pins or to connect them to Digital pin 3 and 4. You can select default Slave mode (DMX Slave only) or control read and writes via Digital pin 2 (In case of DMX Master or DMX Slave with RDM support).
And ther fourth jumper allows you to enable or disable the shield, this is handy in case you use the USART to control the shield and want to update your software... now you only have to disable the shield by placing a single jumper and you are free to go.
This shield works together with the Conceptinetics DMX Library for Arduino, Tinker-it DMX Master and other DMX libraries written for Arduino or AVR.
The shield comes pre-assembled in a box with NEUTRIK XLR Sockets (1x male, 1x female), in comparison with other shields I have seen that use cheap sockets from other brands.
To keep the shield at an affordable price I have populated them with 3 pin XLR sockets, 5 pin versions are only made on request.
Ebay store as well, see the picture on the left. This one is standard available in both 3 pin and 5 pin version. **This version is USART only.
If you have any questions about this shield let me know... I am happy to help you.