Siemens SIMATIC S7 System Manual page 391

Table 9- 66 Example 3 - If an error has occurred during task execution
Error
JogForward
①
The task is started with a positive edge at the input parameter "JogForward" or "JogBackward".
②
While the task is active, the output parameter "Busy" indicates the value TRUE.
③
An error occurred during task execution. When the error occurs, the output parameter "Busy" changes to FALSE and
"Error" to TRUE.
④
When the input parameter "JogForward" or "JogBackward" is reset to the value FALSE, the output parameter "Error"
changes its value to FALSE.
Note
An error occurrence is indicated in the output parameter "Error" for only one execution cycle,
if all the conditions below are met:
The input parameters "JogForward" and "JogBackward" have the value FALSE (but the axis
is still decelerating) and a new error occurs (software limit switch is approached, for
example).
S7-1200 Programmable controller
System Manual, 11/2011, A5E02486680-05
Error
JogBackward
102BTechnology instructions
9.3 Basic motion control
391