ModbusAsyncNetwork

The Modbus network is the main component responsible for servicing the RS485 port (COM2). The ModbusAsyncNetwork component has to be placed under the Drivers folder. The ModbusAsyncNetwork sets parameters such as the communication baud rate and data format, testing, etc., and maintains statistical data.

The ModbusAsyncNetwork component

The ModbusAsyncNetwork component has the following slots:

Status: shows the network status;
Fault Cause: shows the fault cause description;
Enable: switches on/off the Modbus network (true: network enabled, false: network disabled);
BaudRate: allows to set the Modbus RS485 port baud rate (2400, 4800, 9600, 19200, 38400, 57600, 115200 bps);
Stop Bits: displays the number of stop bits (1 bit, 2 bits);
Data Bits: displays the number of data bits (7 bits or 8 bits);
Parity: configures the parity bit (None, Odd, Even, Always1, Always0);
Modbus Type: allows to set the Modbus type (RTU or ASCII);
Steady Time: allows to set the network start-up delay time after the power-up or reset;
Ping Enable: enables devices connection testing function;
Ping Frequency: allows to set the time lapse between the testing message and check device connection;
Down Frequency: allows to set the time lapse between testing message for devices or points, which have gone into the down status (min. value 10s);
Write On Start: writes action in the device’s writable components in the Modbus network after the reset or power-up;
Write On Up: writes action in the device’s writable components in the Modbus network after the connection with Modbus device has been restored;
Write On Enable: writes action in the device’s writable components in the Modbus network after enabling the device;
Fast Rate: allows to set the time between messages in the fast mode poll frequency;
Normal Rate: allows to set the time between messages in the normal mode poll frequency;
Slow Rate: allows the time between messages in the slow mode poll frequency;
Average Poll Time: shows the average time of sending/receipt of one message;
Busy Time: shows the percentage of the Modbus network usage;
Total Polls: shows the total number of messages;
Fast Polls: shows the number of messages sent in the fast mode;
Normal Polls: shows the number of messages sent in the normal mode;
Slow Polls: shows the number of messages sent in the slow mode;
Timeouts: shows the number of lost messages (the difference between messages sent and received);
Errors: shows the number of error messages (for example, with the wrong CRC);
Free points: shows the number of available physical points in the Modbus network.

The ModbusAsyncNetwork component offers the following actions, available in the context menu:

Reset Stats: resets statistics of the Modbus Async network;
Enable: enables the Modbus Async network;
Disable: disables the Modbus Async network.