supporting Sequence of Events

Publication 1732E-UM002A-EN-P - March 2010
68 Using the Module
Timestamp Accuracy = +/- 40 µs.
(1)
Maximum input frequency (for each input) = 250 Hz 50% duty cycle. The
module can provide unique timestamps for input transitions on separate
inputs as long as they occur 25 µs apart. An input that changes state less than
25 µs after another input may receive the timestamp of the first input.
Chapter Summary and
What’s Next
In this chapter, you learned how to use the module. The next chapter describes
interpreting the Status Indicators.
Module Input Pin OFF->ON to Timestamp (Hardware + Firmware) Delay (µs)
Ambient Temp ºC -20 25 60
Voltage
10V DC 23 24 25
24V DC 18 19 19
30V DC 18 19 19
Module Input Pin ON->OFF to Timestamp (Hardware + Firmware) Delay (µs)
Ambient Temp ºC -20 25 60
Voltage
10V DC 59 75 84
24V DC 70 84 93
30V DC 71 85 94
(1)
The timestamp accuracy of +/- 40 µs does not included errors introduced by the module’s clock being tuned
using CIP Sync. This error can be less than one microsecond on a properly configured network.
EXAMPLE
For example, if you are turning ON a
1732E-IB16M12SOEDR module’s input at 24V DC in
25 ºC conditions, the signal propagation delay is 19 µs. If
you want to calculate the actual time the signal reaches the
module’s input pin, subtract 19 µs from the timestamp.
If you are turning OFF an input at 30V DC in 60 ºC
conditions, the signal propagation delay is 94 µs. If you
want to calculate the actual time the signal reaches the
module’s input pin, subtract 94 µs from the timestamp.
The timestamps acquired are accurate to +/- 40 µs as noted
earlier.
The Timestamp data being produced on EtherNet is also
delayed by the input filter setting and the RPI setting.