Variable blocks, Trusted, Communication interface t8151b – Rockwell Automation T8xxx Trusted Communications Interface User Manual
Page 64

Trusted
TM
Communication Interface T8151B
Issue 21 Apr 10
PD-T8151B
64
DAY_HOUR_MIN
Start of block + 2
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
DAY
HOUR
MIN
Bit-Field
Description
DAY
The day-of-the-month value for the timestamp (1…31).
HOUR
The hour value for the time-stamp (0…23).
MIN
The minute value for the time-stamp (0…59).
Table 29 Time-stamp DAY_HOUR_MIN
The SEC_MSEC field is valid only for Time-stamp blocks. It contains the second and millisecond
values for the time-stamp.
SEC_MSEC
Start of block + 3
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
SEC
MSEC
Bit-Field
Description
SEC
The second value for the time-stamp (0…59).
MSEC
The milli-second value for the time-stamp (0…999).
Table 30 Time-stamp SEC_MSEC field
7.2. Variable Blocks
Variable blocks contain information about a variable that has changed state. Each Variable block
spans 4 Modbus registers, and is defined as follows:
Offset
Description
Start of block + 0
HEADER
Start of block + 1
ADDRESS
Start of block + 2
VALUE
Start of block + 3
NOT_USED (always 0)
Table 31 Variable Data
The HEADER field is common to both Time-stamp and Variable data blocks. The TYPE bit-field will
always contain the value 2 for Variable blocks. The bit-fields of the HEADER register are defined as
follows: