Unipulse F600AT Operation Manual page 44

■ B4 terminal function selection
Selection of the KEY_LOCK terminal function from the CODE2
terminal function by the B4 Function Selection setting makes the
following effective.
KEY_LOCK: When the terminal is short-circuited,
all key operations are disabled.
When KEY_LOCK terminal function is selected, measurement code that can
be specified from the outside can be specified by CODE0 terminal,CODE1
terminal.
It is limited to CODE number 0 to 3.
9.SYSTEM
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