How to coommunicate the OTB1E0DM9LP to the vijeio citect directly ?
Inside vijeo citect you may use Modnet protocols. Refer help for modnet driver and various variants like modnet20, modnet30 which clarifies about address offset depending on the devices being used.
OTB supports modbus TCPIP similarly like any device. Configure citect with IP of OTB and all other configuration as you do for PLC etc. Inside OTB you can read only some of registers which are mapped to i/o . Using any undefined in scada may give error and communication may break. For your reference i have attached an FAQ to do configuration on VJC side and inside ports form you may use IP of OTB. Its an FAQ with redundancy , as your scada is standalone do one IOserver1 configuration only. Or use computer express wizard to do fast configuration. To begin with check with modbus tester and see you are getting I/O values. Later do further configuration in citect.