Copyright © 2021 ICP DAS Co., Ltd. All Rights Reserved.
∗
E-mail: [email protected] - 39 -
Items
Description
Type
Operation Mode
Modbus Master: this mode is used to connect Modbus RTU slave
devices. MDCL is acting as a master to send requests to slaves
Modbus Slave: this mode is used to connect Modbus RTU master;
it allows the master to read/write data from/to the MDCL.
Required
Baud Rate
Defines the transmission speed between the MDCL and the RTU
devices. The BaudRate can be set to 1200/ 2400/ 4800/ 9600/
19200/ 34800/ 57600/ 115200 (bps) depending on the RTU device(s)
being used.
Required
Data Bits
Defines the number of data bits in each character. It is fixed to 8 and
the RTU devices need be set to 8-bit data, too.
Required
Parity
Defines the Parity bit. The parity bit can be set to None Parity, Even
Parity or Odd Parity.
Required
Stop Bits
Defines the Stop bits. It can be set to 1 Stop Bit or 2 Stop Bits.
Required
Delay Between
Polls(ms)
Defines the Poll Delay between each scan for Modbus RTU
communication.
Default value: 1000 ms.
Available range: 20 to 6000 (ms).
Required
Timeout(ms)
Defines the period of time that the MDCL module will wait for a
response from a RTU slave device. A timeout is occurred if the MDCL
module does not receive the response within the specified time
period, and then the MDCL will resend the same command
continuously until the number of timeout errors equals to the value
set in parameter
Retry Times
.
Default value: 100 ms.
Available range: 50 to 6000 ms.
Required
Retry Times
Defines the number of consecutive timeout errors are allowed for a
command. If the count of timeout errors equals to the value set in
Retry Times
, the device will be determined to be disconnected.
During the disconnection period, the MDCL will try to establish
communication with the device every 10 seconds instead of
executing this command in polling process, until it receives a correct
response from the device.
Default value: 2.
Available range: 1 to 20.
Required
