Rockwell Automation 1336T ControlNet Frn1.02 Rev 1.5 - Manual (Page 119)

4–77 Using Unscheduled Messaging
Publication 1336 FORCE–5.18 ––March, 1999
Index indicates the index into the 500 word buffer where the last data
point was written.
Timestamp is updated when the last (500 th ) data point is written.
The time stamp has the following format:
This field: Indicates:
Ticks
The number of ticks. One tick equals two
milliseconds. Valid values are 0 through 499.
Seconds
The number of seconds. Valid values are 0 through
59.
Minute
The number of minutes past the hour. Valid values
are 0 through 59.
Hour The hour. Valid values are 0 through 23.
If you request less than 32 trend samples, then run-time data is
padded with zeros. If you request data samples past the end of the
buffer, then run-time data is padded with zeros.
Important: The data samples that you are reading are not being
read from the trend file. Instead, the data samples are
read from the running trend buffer. This buffer is
continually changing at the rate specified by the
sampling rate for that particular trend. You should use
this function when you want to monitor the current
trend sampling.
Example
In this example, Trend 1 is sampling the Velocity Feedback as it is
hovering around 1750 rpm. The data is displayed in internal drive
units.
1 0
N7:10
2 3 4 5 6 7 8 9
N7:90
PLC MSG
Write File
PLC MSG
Read File
Data Format
4128
4128 4093
3
35
4100
4100 4092 4093 4092 4091 4094 4093
N7:100 4092 4091 4092 4091 4091 4092 4093 4094 4094 4093
N7:110 4093 4094 4092 4091 4092
Run File Data
(continued)