Lock And Unlock - Omron NY532-5400 Reference Manual

2 Instruction Descriptions

Lock and Unlock

Lock: Starts an exclusive lock between tasks. Execution of any other task with a lock region
with the same lock number is disabled.
Unlock: Stops an exclusive lock between tasks.
Instruction
Lock Lock Tasks
Unlock Unlock Tasks
Variables
Name Meaning
Index Lock
number
Out Return
value
Bit strings
Index
Out OK
Function
The Lock and Unlock instructions create lock regions. If a lock region in one task is being executed, the
lock regions with the same lock number in other tasks are not executed. Specify the lock number with
Index.
The following figure shows a programming example.
Both task T1 and task T2 contain a lock region with Index set to 1. If the Lock instruction in T2 is exe-
cuted first, the lock region in T1 is not executed until the Unlock instruction is executed in T2.
2-1380
Name FB/FUN
FUN
FUN
I/O Description
Input Lock number
Output Always TRUE
OK
Graphic expression
(@)Lock
EN ENO
Index Out
(@)Unlock
EN ENO
Index Out
Valid range
Depends on data type.
TRUE only
Integers
NY-series Instructions Reference Manual (W560)
ST expression
Lock(Index);
Unlock(Index);
Unit Default
--- 0
--- ---
Times, durations,
dates, and text strings