Siemens SINUMERIK 840D sl Programming Manual page 725

Examples
Example 1: Lock synchronized actions (LOCK)
Program code
N100 ID=1 WHENEVER $A_IN[1]==1 DO M130
...
N200 ID=2 WHENEVER $A_IN[2]==1 DO LOCK(1)
Example 2: Unlock synchronized actions (UNLOCK)
Program code
N100 ID=1 WHENEVER $A_IN[1]==1 DO M130
...
N200 ID=2 WHENEVER $A_IN[2]==1 DO LOCK(1)
...
N250 ID=3 WHENEVER $A_IN[3]==1 DO UNLOCK(1)
Example 3: Interrupt technology cycle (RESET)
Program code
N100 ID=1 WHENEVER $A_IN[1]==1 DO M130
...
N200 ID=2 WHENEVER $A_IN[2]==1 DO RESET(1)
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
Motion synchronous actions
10.5 Technology cycles
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