Vacon NX OPTC2 User Manual

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6
6.1.2 Exception responses
Error response is given when the Slave receives a message without communication errors, but can-
not handle it. Examples of such messages are an incorrect register address, data value or unsup-
ported message. No answer is given if a CRC or parity error occurs or the message is a broadcast
message.
Code
Function
Description
01
ILLEGAL FUNCTION
The message function requested is not recognized by
the slave.
02
ILLEGAL DATA AD-
DRESS
The received data address is not an allowable ad-
dress for the slave
03
ILLEGAL DATA VALUE The received data value is not an allowable value for
the slave.
06
SLAVE DEVICE BUSY The message was received without error but the
slave was engaged in processing a long duration
program command.
Table 8. Exception response codes
Example of an exception response
In an exception response, the Slave sets the most-significant bit (MSB) of the function code to 1. The
Slave returns an exception code in the data field.
Command Master – Slave:
ADDRESS
01 hex Slave address 1 hex (= 1)
FUNCTION
04 hex Function 4 hex (= 4)
DATA
Starting ddress HI
17 hex
Starting address 1770 hex (= 6000)
Starting address LO
70 hex
No. of registers HI
00 hex Invalid number of registers 0005 hex (= 5)
No. of registers LO
05 hex
ERROR
CHECK
CRC HI
34 hex
CRC field 3466 hex (= 13414)
CRC LO
66 hex
Message frame:
01
04
17
70
00
05
34
66

Vacon NX OPTC2 Specifications

General

Brand	Vacon
Model	NX OPTC2
Category	Industrial Electrical
Language	English