ABB 8241, Руководство по эксплуатации

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12
01 83 02 CO F1
Slave Address
01 Illegal Function The message function received is not an allowable action for the 8240.
02 Illegal Data Address The address reference in the data field is not an allowable address for the 8240.
03 Illegal Data Value The value referenced in the data field is not allowable in the addressed slave location.
07 Negative Acknowledgement The function just requested cannot be performed.
08 Memory Parity Error Parity check indicates an error in one or more of the characters received.
The exception response codes sent by the slave are shown in Table 9.1. When a slave detects one of these errors, it sends a
response message to the master consisting of slave address, function code, error code and error check fields.
The response is an exception response sighting ‘illegal data address’. To indicate that the response is a notification of an error,
the most significant bit of the function code is set to 1.
Exception
Response
Code
Exception Response Name Exception Response Definition
01 03 00 FA 00 06 E5 F9
Function Error Check Field (CRC-16)
Slave
Address
Register Start
Offset High
Register Start
Offset Low
Number of
Registers High
Number of
Registers Low
Error Check Field (CRC-16) Function Exception Code
Table 9.1 Exception Response Data
9 EXCEPTION RESPONSES
9.1 Examples
A read register request to read holding register address 251 of slave 01 (undefined address for slave, beyond address limit) is
shown below.