Function: Sequence Counter - Siemens SIMATIC ET 200SP Manual

3.9

Function: Sequence counter

The TM Pulse 2x24V has a sequence counter for each channel that counts completed output
sequences. Successfully completed and unsuccessfully completed output sequences are
counted.
You can monitor the completion of an output sequence with the sequence counter
SEQ_CNT variable in the feedback interface (Page 115).
The counter has a width of 4 bits. After a count overflow, the counter jumps back to 0.
Function of the sequence counter
The sequence counter has the following function in the individual operating modes:
● Pulse output and pulse train
– Function DI configuration is set to "Input": the counter is set to 1 after completion of
– Function DI configuration is set to "HW enable": the counter is incremented after every
● On/Off-delay
– The counter is incremented, with each edge (positive and negative) at the DQ output
● PWM, frequency output, and DC motor
– The counter does not have any function.
When the software enable (SW_ENABLE = 0) occurs, the counter is reset to 0.
Application options
The sequence counter can be used for:
● Detecting (counting) very short pulse sequences
● Counting of output sequences controlled with the hardware enable
Technology module TM Pulse 2x24V (6ES7138‑6DB00‑0BB1)
Manual, 09/2015, A5E35061186-AA
the output sequence (range 0 to 1).
completed output sequence (range 0 to 15).
(range 0 to 15).
Modes and Functions
3.9 Function: Sequence counter
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