Table of Contents
Advertisement
3. Functions
ASGW has the following functions
1. Interface to DCS through Modbus RTU Slave
2. Read and write data for multi-analyzers (GC1000MkII, Analyzer Interface Unit)
3. Mapping of the data between GC1000MkII/Analyzer Interface Unit and ASGW Modbus
4. Alarm information
3.1. Interface for DCS
ASGW has Modbus RTU slave (two serial ports) function as interface to DCS.
Modbus RTU uses two RS232C communication ports. Both ports have the same functions. Two
communication ports can be used at the same time. When two masters request the same address, the last
accepted request is excuted according to update time of ASGW.
3.2. Address mapping
ASGW assembles the data of multiple analyzers, and offers the mapping table to DCS.
Maximum units of GC1000MkII : 31 sets
Function
Coil
Input relay
Holding
register
Input register
When the address of GC1000MkII/ASIU is coil or holding register, writing on the specific address is
available
Refer to the Modbus interface table in section 3.4
3.3. Alarm information
Alarm conditions of communication with analyzers are mapped as input relay.
In operation:
It shows that ASGW accesses to analyzers specified on the mapping file.
Communication failure:
It shows that a time-out error occurs on communication with analyzers. Network line or analyzer failure
may cause the error.
Write failure:
It shows that a write error occurs on analyzer. The failure is reset when the next writing is normal.
3.4. Modbus interface table
ASGW has the function of Modbus RTU Slave.
Modbus interface table
IM 11B06E01-01
Available
address
mapping
01001-09000
11001-19000
41001-49000
31001-39000
for
Available points
8000
8000
8000
8000
3. Functions
GC1000 address area
Coil, Input relay
Input relay
Input
register,
Holding register
Input register
3-1
Advertisement
Table of Contents
