Realtime variables

Variables with the prefix V.RT* are realtime variables. They permit access to the realtime context of the controller. They are synchronised and can both be read and written from the usual context and from the realtime cycle. In this case

• V.RTG.* are channel-specific variables and
• V.RTA.* are axis-specific variables.

A read or write access to a realtime variable causes flushing of the NC channel. For example, flushing the NC channel can result in the error ID 20651 if tool radius compensation (G41/G42) is active.