A control port must first be configured for output in the data logger program before it can be toggled on or off. Consequently, if a selected port doesn’t appear to change, the program may not have the port configured for output. (Refer to the operator’s manual for the data logger for more information.)
The retired CR500 and CR510 have two control ports; however, only one of the ports, control port 1, can be configured for output. Therefore, control port 2 cannot be toggled on or off. It is included on the display so that its status can be monitored.