ElmoMC Multi-Axis Motion Controller-Maestro - Manual (Page 238)

Modbus Slave (Server) Modbus Master (Client)
2.2 Send data to the server
//initialize data array
for i=0:coilsNum-1
staticArr[i]=i%4
end for
if(client.isOpen())
//write data array
retval =client. writeMultipleCoils(
1, &staticArr, coilsNum )
//check results
if( !retval )
TRACE(“Error %!!!”,retval)
end if
if( !client.writeSingleCoil( coilsNum-1, 1 )
TRACE(“Error!!!”)
end if
end if
3. Stop server
server.shutdownServer()
3. Disconnect from server
client.closeProtocol()
12.7 MODBUS Protocol Errors
Error
code
Error message Possible error reason
0xffff Invalid data size or
Index out of range
The size of the storage buffer is out of range or the index
value is less then 1
0 Operation was
successful
Indicates no error
1 Illegal argument error A parameter passed to the function is invalid or out of range
2
Illegal state error
Called in a wrong state; returned by all functions if the
protocol has not yet been opened successfully
3
Evaluation expired
This version of the library is a function limited evaluation
version and has now expired
4
No data table
configured Slave has been started without adding a data table. A data
table must be added by either calling addDataTable or
passing it as a constructor argument.
5
Slave address 0 illegal
for serial protocols A slave address or unit ID of 0 is used as broadcast address
for ASCII and RTU protocol and is, therefore, illegal
64
I/O error class Errors of this class signal a problem in conjunction with the
I/O system
65 I/O error The underlying I/O system reported an error
66 Port or socket open
error The TCP/IP socket or the serial port could not be opened. In
the case of a serial port, it indicates that the serial port does
not exist on the system.
Maestro Software Manual Ethernet/IP Communication
MAN-MASSW (Ver. Q)
12-18