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MINT – IO
REF NO: m25A/om/101
Issue No: 11
Slave ID Registers (42001 & 42006):
The slave ID value is Modbus device address of IO module which is
configured by changing DIP switch. It is read only parameters.
Baud Rate Registers (42002 & 42007):
The baud rate of com1 or com2 can be set to 9600 by writing a 1, set to
19200 by writing a 2, set to 38400 by writing a 3, set to 57600 by writing a 4 or
set to 115200 by writing a 5 to the 42002 or 42007 register.
Parity Register (42003 & 42008):
The parity of com1 or com2 can be set to none by writing a 0, set to even by
writing a 1 or set to odd by writing a 2 to the parity 42003 or 42008 register.
Stop Bits Register (42004 & 42009):
The number of stop bits of
com1 or com2
can be set to 1 by writing a 1 or set to
2 by writing a 2 to the stop bits Register 42004 or 42009.
Data Length Register (42005 & 42010):
The data length register of com1 and com2 is 8. These parameters are read
only.
For ex: If you want set baud rate of communication port one, enter the
required value in the register 42002. Set all the parameters once and then
switch off the power supply to the IO Module. Now switch on the Dip switch 8
on the module to make above settings effective, then, user defined
communication settings will be effective instead of default communication
settings from factory. After power on, the IO Module will have new
Communication settings. Please note that at this point of time, IO module may
not communicate with PC because you may have different settings at
RS232/RS485 converter and also COM port settings in the PC.
2.5.5 Modbus Register Types
There are 4 types of variables which can be accessed from the module. Each
module has one or more of these data variables.
Type Start Address Variable Access
00001 Digital Outputs Read & Write
10001 Digital Inputs Read Only
30001 Input registers (Analog) Read Only
40001 Output registers (Analog) Read & Write(Holding type)
Note:
The Modbus message length must be limited to 100 consecutive read
or write registers. If more registers are required then a new poll group must be
added for the next xxx registers.
