ProSoft Technology MVI56-AFC - Manual (Page 286)

Reference MVI56-AFC ♦ ControlLogix Platform
User Manual Liquid and Gas Flow Computer
Page 286 of 316 ProSoft Technology, Inc.
February 25, 2011
14.5 Archive Data Format
There are 3 columns associated with each archive data:
Column Description
Ofs Shows the offset location of the data in each archive. The maximum offset value
will depend on the Record Size value you configured.
If the value has a "+" value (for example 0+) it means that the data occupies 2
words of data.
Reg Shows the Primary Modbus Slave Address of the data. This is a meter-relative
address. For example: a Reg value of 890+ for meter 1 would be equivalent to
Modbus addresses 8890 and 8891.
Description Data Description.
14.5.1 Timestamp Date and Time Format
The date and time format used in the archives is stored in a highly compressed
form in order to represent the date and time using only 2 words of data:
Word Description
0 Date
1 Time
In order to extract the information from the date format use the following
arithmetic:
Date Word
Year = ([Bits 15 thru 9] from Word 0) + 1996
Month = ([Bits 8 thru 5] from Word 0) + 1
Day = ([Bits 4 thru 0] from Word 0) + 1
Time Word
Hour = ([Bits 15 thru 11] from Word 1)
Minute = ([Bits 10 thru 5] from Word 1)
Second = ([Bits 4 thru 0] from Word 1 )* 2
The first 10 words of data (archive header) are common for all archives: