4-4
IM XL100C-E
4.4
Setting the Modbus Master Function
Set the items below to use the Modbus master function.
• Communication Interval
The cycle at which data is read from other devices. Select the read cycle from the
following:
100 ms, 200 ms, 500 ms, 1 s, 2 s, 5 s, or 10 s
• Timeout Value
Timeout occurs if a response is not received from the specified slave device within the
time specified here (timeout value) after a command is sent from the XL100. The
XL100 repeats the operation of sending a command and waiting for a response for
the number of times specified by the retrial value. If no response is received even
after waiting the timeout value for all retrials, the XL100 stops sending commands to
the slave device for a period equal to 10 times the timeout value. Then, the XL100
tries again. For details, see section 4.5, “Data Dropout Handling of the Modbus
Master.”
Select the timeout time from the following:
100 ms, 200 ms, 500 ms, 1 s, 2 s, 5 s, 10 s, or 1 min
• Retrials
This is the number of times to retransmit the command when there is no response
from the specified slave device. If no response is received even after retrying the
number of times specified here, the XL100 stops sending commands to the slave
device for a period equal to 10 times the timeout value. Then, the XL100 tries again.
For details, see section 4.5, “Data Dropout Handling of the Modbus Master.”
Select the number of retrials from the following:
OFF (0), 1, 2, 3, 4, 5, 10, or 20
• Commands
The commands are used to read the data in the register of slave devices into the
communication input data of the XL100 at the read cycle. Consecutive registers of the
same data type in a slave device can be registered as a single command and read
into consecutive communication input data.
• Enabling/Disabling Commands
Turn ON the command registration line to be used. Up to 32 commands can be
registered.
• Read channel (First CH, Last CH)
Set the communication input data (CO01 to CO32) to which the data loaded from
the slave device is to be assigned.
• Address
Specify the address of the slave device from the following:
1 to 247
• Register
Specify the register number of the slave device. Since 32-bit data is assigned to
two registers, specify the smaller register number (see “Type” below).
Input register: 30001 to 39999, 300001 to 365535
Hold register: 40001 to 49999, 400001 to 465535
• Type
Specify the data type assigned to the Modbus register of the slave device.
• INT16
Specify this type when a “16-bit signed integer” is assigned to the Modbus
register.