Carlo Gavazzi Controls S.p.A.
–
32100
–
Belluno
INFO: www.carlogavazzi-automation.com Phone +39.
0437 355811
User Manual
Modbus Master / SNMP Agent
Document code: SIU-SNM-01_ENG
Revision 1.0
2020-12-03
Page 14 / 25
SET ACCESS
By pressing the “
Set Access
” button from the main window the window “Set Access” appears.
This window is divided in two parts, the "Modbus Read" (Fig. 4a) and the "Modbus Write " (Fig. 4b).
The first part "Modbus Read" is used to read the data from the Modbus slaves, and make them available
to read from the SNMP manager.
The second part "Modbus Write " is used to write the data that arrives from the SNMP manager into the
slaves Modbus.
M
ODBUS
R
EAD
The means of the fields are:
In the field “
Slave ID
” the address of the Modbus device to read is defined;
In the field “
Type
” the data type of the register to read is defined. It is possible to choose between
the following:
o
Coil Status;
o
Input Status;
o
Holding Register;
o
Input Register.
In the field “
Address
” the starting address of the register to be read is defined (in decimal);
In the field “
NPoint
” the number of consecutive registers to be read is defined (number of words);
In the field “
Poll Time
” the delay time to make the request is defined;
In the field “
Max Error
” the number of consecutive errors that the converter waits before
suspending the request until the next reboot is defined. If is set to
‘0’ this function is disabled;
In the field “
Position
” the address of the SNMP array where placing the information is defined.
Each position corresponds to a byte;
In the field “
Start Bit
” the starting bit of the first byte of the field “Position” is defined. Valid only for
the “Coil Status” and “Input Status”;
If the field “
Swap
” is checked, the data from the Modbus registers are swapped;
If the field “
Swap Word
” is checked, the words of the data read are swapped between them;
In the field “
Mnemonic
” the description for the request is defined.
