Changing parameters concerning the transmission configuration will only take effect after restarting the module or reload settings–register (40001).
Firmware Version and Module Type (30001)
The register contains type and firmware version of module.
Low byte contains information about the type of module in accordance with the table below:
High byte contains the module firmware version multiplied by 10.
In the 30001 register the number is 2049010 = 0x500A16. It means that it is a module iSMA-B-W0202 (0x50) with firmware in version 1.0 (0x0A16 = 1010).
Counter of Received Messages (30004)
The 32-bit register with the number of valid Modbus messages received by the module from the last power up. The value is reset after a power cycle or after changing transmission parameters (baud rate, stop bits, parity, etc.).
Counter of Error Messages (30006)
The 32-bit register with the number of error Modbus messages received by the module from last power up. The value is reset after a power cycle or after changing transmission parameters (baud rate, stop bits, parity, etc.).
Counter of Sent Messages (30008)
The 32-bit register with the number of Modbus messages sent by the module from last power up. The value is reset after a power cycle or after changing transmission parameters (baud rate, stop bits, parity, etc.).
Up Time (30012)
The 32-bits register contains module working time in seconds from last power up or module reset.
Device Actions (40001)
Setting the 40001 register according to the table below enables 1 of 3 available actions: reset module, reload settings, and set to default.
Type of Action
Reset of device
Reload settings (RS485, Radio)
Set device to default
Modbus Protocol Type (40134)
The register contains parameters, which define the Modbus protocol type (RTU or ASCII).
Modbus Address (40135)
The register contains information about the Modbus address of the module. The default address is 1.
Baud Rate (40136)
The register contains information about the baud rate.
Particular register value determines the baud rate in accordance with the table below.
Stop Bits (40137)
The value of the register determines the number of stop bits in accordance with the following table:
No. of Stop Bits
Data Bits (40138)
The value of the register determines the number of data bits transmitted in a single byte according to the following table:
No. of Data Bits
Parity Bit (40139)
Each byte of data being transferred may be additionally protected with a parity bit added before stop bit (bits).
The method of calculating parity bit is determined according to the following table:
Type of Parity Bit
Odd (number of all ones in a byte is odd)
Even (number of all ones in a byte is even)
Response Delay Time (40140)
The register contains the value determining the number of milliseconds to wait before the unit answers the question. This time is used to extend the interval between question and answer. The default value of 0 means no delay (the answer is sent once during the 3,5 character required by the protocol Modbus RTU).
Watchdog Time (40141)
The register specifies the time in seconds to watchdog reset. If the module does not receive any valid message within this time, digital outputs are set to default state, which is determined by the value in the 40142 register.
This feature is useful if, for some reason, there is an interruption in data transmission and for security reasons the output must be set to an appropriate state in case of danger to the safety of persons or property.
Setting 0 s disables the watchdog. The default value is 15 seconds.
Watchdog for Radio
If the radio does not receive the correct data packet for 180 seconds, the radio module is restarted. The time of 180 seconds is a constant value.