Tcp/Udp Message Service Specifications; Tcp/Ip And Udp/Ip Message Format - Omron NX-series User Manual

9 TCP/UDP Message Service Function
9-3
TCP/UDP Message Service Specifica-
tions
The Communication Control Unit supports a TCP/UDP message service based on the following speci-
fications.
Maximum number of clients that can
connect at one time
Maximum message size
Maximum data size of NX output
Maximum data size of NX input
Port number
*1. 2 bytes are used for the attribute field in the explicit message UDP/IP command and TCP/IP command.
9-3-1

TCP/IP and UDP/IP Message Format

Command Format
The following format is used to send commands (TCP/IP messages or UDP/IP messages) from a de-
vice on Ethernet. The least-significant byte for multi-byte parameters is in the lower address.
The command format is shown below.
The examples of values in the table are the parameter values in little-endian format when the Vendor
ID (instance attribute ID 01 hex) in the Identity object (class ID 01 hex) is read.
+0 Message sequence number
+2 Reserved 1
+4 Data size
+6 Reserved 2
+7 Service code
+8 Class ID
+10 Instance ID
+12 Attribute ID
+14 Data
9 - 4
Item
64 (TCP: 32, UDP: 32)
Request: 492 bytes
Response: 496 bytes
490 bytes
496 bytes
Default: 64,000 decimal
The port number can be changed by Network Configurator (restart
required). Acceptable port number ranges are shown below in dec-
imal format.
•
•
•
NX-series Communication Control Unit Built-in Function User's Manual (Z396)
Name
*1
*1
1,024 to 2,221
2,223 to 44,817
44,819 to 65,535
2 bytes
2 bytes
2 bytes
1 byte
1 byte
2 bytes
2 bytes
2 bytes
490 bytes max.