Issue
Can 2 comm ports be enabled when using the RTU Xdriver?
Product Line
Andover Continuum
Environment
- Continuum
- 9680
- 99xx
- 9640
- 4040
- Xdriver
- Modbus RTU
Cause
At times it is necessary to have multiple ports enabled for Xdrivers
Resolution
The ability to enable 2 comm ports using Xdrivers can be done, but is not recommended by the Xdriver developers or supported by PSS.
The RTU Xdriver is poll on demand. This type of driver can request a lot of data and starve the CPU on the controller which then makes the polling irregular. If 2 ports are being used then there are typically more devices being added and therefore more points increasing the requests and demand on the controller's CPU.
Use one program to control the polling on both ports. Two programs attempting to control the polling asynchronously will cause communication issues.
