BONFIGLIOLI Vectron Agile, Communications Manual

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Modbus Agile 02/2011 34
Protocol
Exception Code
The following exception codes can occur:
2 ILLEGAL DATA ADDRESS − Parameter unknown
3 ILLEGAL DATA VALUE − No. of bytes in the data field too small or too large
4 SLAVE DEVICE FAILURE − Error on writing the parameter
Exception Codes are described in detail in Chapter 7.3.9 "Exception Codes".
Example of a Modbus ASCII telegram: see chapter 9.2.2.4.
Example of a Modbus RTU telegram: see chapter 9.1.2.4.
7.3.7 Function Code 8, Diagnostics
This function code is used to access the Modbus diagnostic counters that are supported by the inver-
ter. Each counter can be obtained by a sub-function code bound to the counter number. All of the
counters can be cleared using the hexadecimal sub-function code 0x0A.
The following sub-function codes are supported:
Sub
Function Name Description
0x0A Clear all counters Sets all counters to zero
0x0B Return Bus Message Count No. of valid messages received
(with all addresses)
0x0C Return Bus Communication Error Count No. of messages with CRC or
Parity/Framing/Overrun error
0x0D Return Bus Exception Error Count No. of Exception Responses sent
0x0E Return Slave Message Count No. of messages received
(with slave address)
0x0F Return Slave No Response Count No. of Broadcast messages received
0x10 Return Slave NAK Count not used, return value is always 0
0x11 Return Slave Busy Count not used, return value is always 0
0x12 Return Bus Character Overrun Count No. of messages with Overrun error
Request (Sub-function 0x0A, Clear all Counters):
Start Frame (RTU oder ASCII mode)
Address
Function Code
1 Byte 0x08
Sub-function 2 Bytes 0x000A
Data 2 Bytes 0x0000
CRC or LRC & Endframe
Response:
Start Frame (RTU oder ASCII mode)
Address
Function Code
1 Byte 0x08
Sub-function 2 Bytes 0x000A
Data 2 Bytes 0x0000
CRC or LRC & Endframe