Function Codes; Function Code List; 03 Hex: Reading Of Multiple Registers - Omron K6CM User Manual

9-2

Function Codes

This section describes function codes that can be used with Modbus TCP.
9-2-1

Function Code List

The function codes that can be used are as follows.
Function code
03 hex
06 hex
10 hex
9-2-2

03 hex: Reading of Multiple Registers

This function can read the contents of multiple registers starting from the specified address.
Frame Configurations
The frame configurations of Modbus TCP are as follows.
 Request
(1)
00 00
2
(1): Transaction ID
(2): Protocol ID
(3): Number of bytes trans-
ferred
(4): Unit ID
(5): Function code
(6): Start address
(7): Number of words to read
K6CM Motor Condition Monitoring Device User's Manual (N219)
9 Monitoring and Setting Using the Modbus TCP Devices
Name
Reading of multiple
registers
Operation command Used to instruct Software reset and Max./min. reset.
Writing of multiple
registers
(2) (3)
00 00 00 06
2 2
Specify any value. For example, 0000 hex is used in this explanation.
Specify 0000 hex.
Specify the total number of bytes of (4) and the successor. In the above case,
it is from (4) to (7), so it is 0006 hex.
Specify FF hex.
Specify 03 hex (Reading of multiple registers).
Specify the address to start reading.
Refer to 9-3 Register Address Lists on page 9-8.
Specify the number of words of the register to be read. The maximum value is
26 (001A hex).
Usages
Used to read the monitor information, setting information, pro-
duction information, IP address, etc.
Used to set the IP address, K6CM initial setting, etc.
(4) (5) (6)
FF 03
1 1 2
(7)
←Hex
←
Number of bytes
2
9 - 3
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