Save position value
The latch function enables the current position value (0x60n1:01 "Position") to be stored in a separate process data, independent of the cycle time. This function can be triggered via:
- Digital input: via a positive or negative edge at the digital input
Save position value via digital input ("Enable latch on digital input", index 0x70n0:03
- Index 0x80n1:1B "Digital input latch polarity" can be used to specify the level at which the position value is to be stored in a separate process data.
- 0: input disabled
- 10: positive edge
- 11: negative edge
- Index 0x70n0:03 "Enable latch on digital input" = TRUE
- At the first parameterized edge at the digital input the current position value is stored in index 0x60n1:02 "Latch value".
- For confirmation the "Latch extern valid" bit in index 0x60n0:0A is set to TRUE.
- A renewed activation for saving the position value can only take place when index 0x70n0:03 has been set to FALSE.
- Index 0x80n0:06 "Enable continuous digital input" can be used to specify whether it is necessary to reactivate the command
- FALSE:
The following pulses at the digital input have no influence on the latch value in index 0x60n1:02 "Latch value" if the bit in index 0x70n0:03 is set.
A new position value can only be written to index 0x60n1:02 "Latch value" when index 0x60n1:0A "Latch extern valid" is FALSE. - TRUE:
The position value 0x60n1:01 "Position" is written to index 0x60n1:02 "Latch value" for each parameterized edge at the digital input.
Renewed activation of the index 0x70n0:03 is not necessary. The index 0x60n0:0A "Latch extern valid" is set to TRUE on a registered edge for a PLC cycle. - The status of the digital input can be recorded via index 0x60n0:08 "Digital input"