Example code on how to control a Roboteq SDC2130 with an Arduino
Product Page for the Roboteq SDC2130 (TE-144-030) http://www.superdroidrobots.com/shop/item.aspx/roboteq-sdc2130-2x20a-30v-motor-controller-with-encoder-input/1168/
Datasheet (Has pinout of the IO connector on page 6) http://roboteq.com/index.php/docman/motor-controllers-documents-and-files/documentation/datasheets/sdc21xx-datasheet/63-sdc21xx-datasheet/file
User Manual (Detailed information on communication protocol) http://roboteq.com/index.php/docman/motor-controllers-documents-and-files/documentation/user-manual/7-nextgen-controllers-user-manual/file