Acknowledge timestamp latching timestamp data – Rockwell Automation 1732E-OB8M8SR EtherNet/IP Dual Port 8-Point SOE Input and Scheduled Output Modules UM User Manual

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Rockwell Automation Publication 1732E-UM003B-EN-E - March 2014

Chapter 10 Use the Sequence of Events Input and Scheduled Output Modules

Acknowledge Timestamp Latching Timestamp Data

In most cases, Timestamp Latching is enabled. This means that once the module
timestamps an input transition, the module will not timestamp another
transition in the same direction on the same input until you acknowledge the data
from the first timestamped transition; when you acknowledge data, you clear it
from the module

.

To clear data from the module, you must acknowledge them via the module
output tags. You can clear data in the following ways:

• Clear latched timestamp data for specific inputs – As data is

acknowledged, it is cleared from the module, and the module will once
again timestamp the first new transition for the input in the cleared
direction(s).

To clear timestamp data for specific inputs, you must complete the
following steps:
a. Write to the EventAck output tag (

O.EventAck). This tag determines

which edge you will clear (acknowledge).

• 0 = clear only the falling edge timestamp (I.Timestamp[x].OnOff )
• 1 = clear only the rising edge timestamp (I.Timestamp[x].OffOn)
• 2 = clear both the falling and rising edge timestamps
b. Change the NewDataAck output tag (

O.NewDataAck.x) to a rising

edge (set the tag =1). This tag determines which inputs will be cleared
(acknowledged). There are 8 bits (x = 0…7) that can be transitioned;
each corresponding to an input. More than one bit can be transitioned
at the same time.

• If the bit = 0, change the bit to 1.
• If the bit = 1, change the bit to 0, wait for at least one RPI, and change

the bit to 1.

The corresponding I.EventOverflow and I.NewData tags are also cleared.

Clear all latched data for the module – This transition erases all

timestamp data from the module, clearing data from all inputs
simultaneously. Once the data is cleared, the module timestamps the first
transition in each direction for each input and sends the data to the
controller (assuming those inputs are configured with Timestamp Capture
enabled in each direction).

To clear all data for the module, transition the O.ResetEvents tag to 1.
– If the bit = 0, change the bit to 1.
– If the bit = 1, change the bit to 0, wait for at least one RPI, and change

the bit to 1.

The following figure shows when to clear data from the module. In this example,
the module sent input data to the controller, and the controller copied the

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