Allen-Bradley SLC 500 Quick Start Manual page 35

WORD 15 14 13
0 EN ST DN
1 Reserved (Target Node Not Used)
2 Number of Elements
3 Not Used
4 File Type (based on local source or destination address)
5 Not Used
6 Not Used
7 Reserved (Internal Messaging Bits)
8 Message Timer Preset
9 Message Timer Scaled Zero
10 Message Timer Accumulator
11 Data Length in Bytes
12 AO=1 Reserved (Internal Messaging Bits)
13 Reserved
14 Logical ASCII Address String Length including NULL Termination Character (bytes)
15 First Byte of ASCII Address String
16 Third Byte of ASCII Address String
55 Eighty-First Byte of ASCII Address String
56
First Byte of IP Address String
57 Third Byte of IP Address String
76 Forty-First Byte of IP Address String
77 Reserved
78–92 Reserved for Future Use
The IP Address string format is up to 42 ASCII characters including a terminating NULL character. The first byte in the array is the
left-most character in the string as written. For example: If the IP Address is 423.156.78.012, the first byte is the ASCII character "4". If
the MSG destination is an INTERCHANGE client on a host computer, the destination is specified as "client" and stored as a NULL
terminated string.
Communicating on the Ethernet Network
SLC 5/05 Channel 1 (Ethernet port)
MSG Control Block with Logical ASCII Addressing
valid for PLC-5 typed read or write only
12 11 10 09 08
ER CO EW NR TO
07 06 05 04 03
Error Code
Reserved
Second Byte of ASCII Address String
NULL Byte of Longest ASCII Address String
Second Byte of IP Address String
NULL Byte of Longest IP Address String
Reserved (Ethernet Message Type); must be 0
4–5
02 01 00
WQ
Publication 1747-10.4