1
it back to the TCP clients after receiving Modbus TCP/IP clients instructions. This method
can greatly reduce the waiting time for the client to access to the station and improves the
refresh rate.
3.1.3. Data storage area
Data storage is divided into five parts.
Part 1. "Coil" (DO) storage area, 8192 points in total.
Part 2. "Discrete magnitude input" (DI) storage area,8192 points in total.
Part 3. "Input register" (AI)storage area, 2048 points in total.
Part 4. "Hold register"(AO) storage area, 2048 points in total.
Part 5. "System diagnostic" (DO) storage area, it stores the station equipment working
status, 263 points in total. And it could access to the “system diagnostic” area and obtain
the slave information. This could be used for setting the disconnection alarm.
The distribution of the data storage area and the scope of the address coding are shown in
below.
Table 3.1 Data store address table
Item
Storage type
Description
Storage
capability
Address range
1
Area 0
Coil
8192 Bit
0x0000~0x1FFF
2
Area 1
Discrete
magnitude input
8192 Bit
0x0000~0x1FFF
3
Area 3
Input register
2048 Word
0x0000~0x07FF
4
Area 4
Hold register
2048 Word
0x0000~0x07FF
5
Area 3
System
diagnostic
263 Word
0x2000~0x2106
