Delta DVP-15MC Series, Operation Manual

Page: 911 / 972

Appendix A. Modbus Communication
A-7
A_
return reg_crc; // the value that sent back to the CRC register finally
}
A.3 Modbus Function Codes Supported

The function codes which are supported by DVP-15MC series motion controller are listed in the
following table when COM2 port is possessed by the motion control module.
Function
code
Explanation Available register
16#01
Read output bit register values; the data of 256 bits at
most can be read at a time
%QX
16#02
Read bit register values; the data of 256 bits at most
can be read at a time
%IX,%QX
16#03
Read one single or multiple word register value; the
data of 100 words at most can be read at a time.
%MW,%QW,%IW
16#05 Write one single bit register value. %QX
16#06 Write one single word register value. %MW,%QW
16#0F
Write multiple bit register value; the data of 256 bits at
most can be written at a time.
%QX
16#10
Write multiple word register value; the data of 100
words at most can be written at a time.
%MW,%QW
A.4 Modbus Exception Response Code Supported

Exception response codes supported by DVP-15MC series motion controller are listed in the
following table.
Exception
response
code
Explanation
16#01
Illegal command codes: the command codes in the command message
which PLC receives are invalid.
16#02
Illegal register address: the address in the command message received is
invalid.
16#03
Illegal register value: the data in the command message received by PLC
are invalid.
16#07

Check sum fault

Check if the check sum is correct.

Illegal command message

Too short command message

The length of the command message exceeds the valid range.