Latch Function (Job 10) - Siemens simatic et 200s Operating Instructions Manual

1PosUniversal/Digital
7.6 Functions of the 1PosU
7.6.15

Latch Function (JOB 10)

Definition
The latch function allows you to store the actual value at an edge at the DI2 digital input. You
can use this function, for example, to detect edges or measure lengths.
Supply the control interface with the desired edge, and activate JOB 10.
If the 1PosU detects the preset edge at the DI2 digital input, it stores the associated actual
value, displays it as a feedback value and sets the feedback bit LATCH_DONE = 1.
You can then activate the latch function again.
Latch Function and Reference Point Run or Reference Signal
If the 1PosU synchronizes at the same edge, it stores the actual value before it assigns the
reference point coordinates.
Effect on the MODEs
MODEs are not affected by JOB 10.
Control Signals: Latch Function
Address
Byte 4
Byte 5
Feedback Signals: Latch Function
Address
Byte 4
Bytes 5 to 7
354
Assignment
Bits 4.7 to 4.4 :
Bit 7 6
1 0
Bit 0: JOB_REQ
Bit 1: Latch at negative edge at DI2
Bit 0: Latch at positive edge at DI2
Assignment
Bit 2: LATCH_DONE
Bit 1: JOB_ERR
Bit 0: JOB_ACK
Feedback value: Actual value at the edge at DI2
for incremental encoder (linear axis: 0 to 16 777 215; rotary axis: 0 to end of rotary
axis-1), at SSI encoder (0 to encoder range - 1)
5 4
JOB 10 = Latch function
1 0
Operating Instructions, 05/2007, A5E00124871-04
ET 200S Positioning