Hey panic mode and SkyFire,
thanks for your help and detailed description regarding my described problem.
The sending and receiving using the I/Os of the KRC4 is working now.
Meanwhile I also got in contact with the customer service of KUKA, and he suggested to use the robot sensor interface instead of using the I/Os of the KRC4 in order to send new position data to the robot from the plc based on calculations from external sensor data and for retrieving the new position of the robot.
Does some of you have experience on this topic, and could give me an advise? I am already reading through the manual of the robot sensor interface 4.0, since this is the version I have installed on the robot, and to get an idea of its functionality.
BTW. I hope it is fine to ask here in this thread, because at the beginning the original problem of DP18 was very similar to mine, otherwise I can start a new thread, in case I am violating some guidelines.
Many thanks and best regards