The SGDA04VS is a speed and torque control drive.
The RS232 is for drive setup and commissioning only. The SGDA is controlled via pins 1 & 2 (torque) or pins 3 and 4 (speed) with a +-10v analog reference signal. This signal is usually supplied from a motion controller of some sort. Galil, PMAC, Fanuc, Allen Bradley, etc...
Here is a nice page that shows the wiring of the SGDA servo drive. http://www.mech.northwestern.edu/cou...ervomotors.htm
Also, that looks like a Seidel SM series servo motor. You will have a difficult time running it with the SGDA if it is. The SM series motors have resolvers for feedback reference to the drive and the SGDA is designed for quadrature encoder feedback. The Yaskawa drives were designed to run primarily with the Yaskawa servo motors. The motors must be matched by both wattage and voltage. The V in your SGDA-04VS signifies a 200 volt drive your motor also needs to be a 200 volt motor. The SGDA uses the SGM series of motors. A SGM-04V312 or a SMG-04A312 are appropriate motors for your drive.
If you want to run that Seidel motor, consider sourcing a Kollmorgen ServoStar 400 or 600 in the right wattage. That motor looks like a 500 watt drive to me, just going by the size of the motor as compared to the Yaskawa drive.
See if you can get the servo motor's information by trying a magnifying glass or something. I know it's hard to read, but unless you can get it's make/model, it's going to be trial and error (mostly error) to find something that will run it.