Manual

WEB SERVER CPU MODULE USER’S MANUAL FC9Y-B1278 9-7
9: MODBUS TCP COMMUNICATION
Modbus TCP Server
When the Web server CPU module is configured as the Modbus TCP server, Modbus TCP client devices can access and
communicate with the Web server CPU module.
When the Web server CPU module receives a valid request from a Modbus TCP client device, the data is read or written
according to the request received. The communication data received from Modbus TCP clients are processed at the END
processing.
Modbus TCP Server Specifications
*1: When timeout occurs, the MicroSmart discards the received data and waits for the first frame of the next valid communication.
*2: The value when all server connections are configured as Modbus TCP server is indicated.
Address Map
*1: Addresses generally used for Modbus communication. For details about the calculation method of Modbus addresses for
MicroSmart devices, see chapter 12 of FC5A user’s manual basic volume.
Parameter Modbus TCP Server
Slave Number Ignored
Response Time 1.5 ms
Receive Timeout *1 500 ms
Number of Clients that can Access Simultaneously *2 8 maximum
Port Number 502 (can be changed between 0 and 65535)
Supported Function Code
01 Read Coil Status
02 Read Input Status
03 Read Holding Registers
04 Read Input Registers
05 Force Single Coil
06 Preset Single Register
15 Force Multiple oils
16 Preset Multiple Registers
Modbus Device
Name
Modbus Address
Map (Decimal)
*1
Communication
Frame Address
MicroSmart Device
Applicable
Function Code
Coil
(000000 and above)
000001 - 000504 0000 - 01F7 Q0 - Q627
1, 5, 15
000701 - 000956 02BC - 03BB R0 - R255
001001 - 003048 03E8 - 07F7 M0 - M2557
009001 - 009256 2328 - 2427 M8000 - M8317
Input Relay
(100000 and above)
100001 - 100504 0000 - 01F7 I0 - I627
2101001 - 101256 03E8 - 04E7 T0 - T255 (timer contact)
101501 - 101756 05DC - 06DB C0 - C255 (counter contact)
Input Register
(300000 and above)
300001 - 300256 0000 - 00FF T0 - T255 (timer current value)
4
300501 - 300756 01F4 - 02F3 C0 - C255 (counter current value)
Holding Register
(400000 and above)
400001 - 408000 0000 - 1F3F D0 - D7999
3, 6, 16
408001 - 408500 1F40 - 2133 D8000 - D8499
409001 - 409256 2328 - 2427 T0 - T255 (timer preset value)
3
409501 - 409756 251C - 261B C0 - C255 (counter preset value)
410001 - 450000 2710 -C34F D10000 - D49999 3, 6, 16