Labview modbus code how to#
Labview modbus code code#

Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. Otherwise, it describes the error status that this VI or function produces. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information.

Labview modbus code code#

The exception code mapping is as follows: 0 No error 1 Illegal function 2 Illegal data address 3 Illegal data value 4 Failure in associated device 5 Acknowledge 6 Busy, rejected message 7 NAK-Negative acknowledge For more information about these error codes, refer to your device's documentation. Coils represents the data read from the slave. The class matches that of the VISA resource name input.

Labview modbus code how to#

The source string includes the name of the VI that produced the error, what inputs are in error, and how to eliminate the error. If status is TRUE, code is a negative error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.

If an error occurs while this VI or function runs, the VI or function runs normally and sets its own error status in error out. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. Timeout specifies the maximum time period, in milliseconds, that the VI waits for the slave's response before throwing an error. For example, if Starting Address is 0 and Quantity is 4, the VI reads coils from the slave at address 0, 1, 2, and 3. Per MODBUS convention, the register address of the slave device is calculated by subtracting 1 from the register name that you specify in the master device configuration software. Organizations that help homeless families Refer to your device's documentation to find the coil address mapping. This address is sometimes referred to as offset.

Starting Address is the first address location of the coil to read.

This control also specifies the session and class. VISA resource name specifies the resource to be opened. Slave Address This is the address of the slave you are communicating with. Mode RTU Data is represented in binary format. This is the address of the slave you are communicating with. The master uses this VI to read the slaves' coils. Pb_user_ / Octo/ Labview modbus master library / comments