West Control Solutions Pro-EC44 - Manual (Page 119)

Pro-EC44 2-Loop Graphical Profile Controller & Recorder
Pro-EC44 Product Manual - 59540-1 October 2013 Page 112
Function 08 - Loopback Diagnostic Test
QUERY: Function 08 - Loopback Diagnostic Test
Func
Code
Diagnostic
Code
Value
08 00 00 HI LO
RESPONSE: Function 08 - Loopback Diagnostic Test
Func
Code
Sub-function Value
08 00 00 HI LO
Note: The Response normally returns the same data as the loopback query.
Other diagnostic codes are not supported.
Function 16 - Write Multiple Registers (0x10 Hex)
Writes consecutive word (two-byte) values starting at the specified address.
QUERY: Function 16 - Write Multiple Registers (0x10 Hex)
Func
Code
1
st
Write
Address
Number of
Words
Byte
Count
1st Word etc Last Word
10 HI LO HI LO xx HI LO → HI LO
RESPONSE: Function 16 - Write Multiple Registers (0x10 Hex)
Func
Code
1st Word
Address
Number of
Words
10 HI LO HI LO
Note: The maximum number of data bytes that can be written in one message is
253 bytes.
Function 23 Hex - Read / Write Multiple Registers (0x17 hex)
Reads and writes the requested number of consecutive words (two-bytes) starting at the
specified addresses.
QUERY: Function 23 Hex - Read / Write Multiple Registers (0x17 hex)
Func
Code
1
st
Read
Address
Number of
Words
1
st
Write
Address
Number of
Write Words
Byte
Count
Values to Write
1st Word etc Last Word
17 HI LO HI LO HI LO HI LO xx HI LO → HI LO
RESPONSE: Function 23 Hex - Read / Write Multiple Registers (0x17 hex)
Func
Code
Byte
Count
Read Data
1st Word etc Last Word
17 xx HI LO → HI LO
Note: The maximum number of data bytes that can be read and written in one
message is 253 bytes.
Exception Responses
If a QUERY is sent without a communication error, but the instrument cannot interpret it, an
Exception RESPONSE is returned. The exception response consists of a modified version of
the original function code and an exception code that explains what was wrong with the
message. Possible exception responses and their reasons are: