N10:20 – Rockwell Automation 1747-DTAM-E,D17476.1 Data Table Access Module (DTAM) User Manual
Page 79
Message Capability
8-19
Publication 1747-6.1
The following example is the data monitor display for the 12-word
message instruction in Rung 0:
Below is the data monitor display for the message control block,
followed by an explanation of the data file.
7-word message control block: N7:0 through N7:6
N7:0 = 0
message status
N7:1 = 2
DTAM node address
N7:2 = 12
message length
N7:3 = 100
offset (overwrite capability)
N7:4 through N7:6 = unused
Below is the data monitor display for the message local source file,
followed by an explanation of the data file.
For ease of viewing, N10:0 through N10:7 are displayed in the ASCII radix. The rest of the file is
displayed in Decimal.
12-word local source file: N10:0 through N10:11
N10:0 through N10:7
8-word message text
N10:8 through N10:11
data entry destination address
In this example the data entry destination address is N10:20. Memory
locations N10:8 through N10:11 are assigned as follows:
Read/Write:
Target Device:
Control Block:
Local Source File Address:
Target Node:
Target Offset:
Message Length in elements:
WRITE
485 CIF
N7:0
N10:0
2
100
12
ignore if timed out:
to be retried:
awaiting execution:
error:
message done:
message transmitting:
TO
NR
EW
ER
DN
ST
0
0
0
0
0
0
0
Address
0
1
2
3
4
5
6
7
8
9
N7:0
0
2
12
100
0
0
0
0
0
0
Address
0
1
2
3
4
5
6
7
8
9
N10:0
E n
t e
r
N e
w
V a
l u
e?
7
10
N10:10
20
0
0
0
0
0
0
0
0
0
N10:20
File Type
File Number
Element
N10:8=7
N10:9=10
N10:10=20