Siemens SINUMERIK 840D sl Operating Manual page 569

Simulation
In the simulation window, actual values are displayed for a maximum of 4 channels
simultaneously as well as the actual block.
You can toggle between displaying the traversing paths and the channel zero point using the
"Channel+" and "Channel-" softkeys.
Axes, which are located in several channels, are displayed grayed-out if the setpoint comes
from a different channel.
Channel status
When required, channel messages are displayed in the status display.
Turning
Operating Manual, 02/2012, 6FC5398-8CP40-3BA0
Machine manufacturer
Please refer to the machine manufacturer's specifications.
10.5 Multi-channel functionality for large operator panels
Multi-channel support
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