BC7300
37
BC7300 Error Answers
EXCEPTION RESPONSE
When the user sends the slave either a request or information that the Bus
Coupler does not understand, the BC7300 responds with an error report.
This answer contains the function and the error code. 0x80 is added to the
value returned by the function.
Code Name
Meaning
1
ILLEGAL FUNCTION
Function not implemented
2
ILLEGAL
DATA
ADDRESS
Invalid address or length
3
ILLEGAL DATA VALUE
Invalid parameter
•
Diagnostic functions
•
Incorrect number of read/write
accesses to the register
4
SLAVE DEVICE ERROR Watchdog or K-Bus error
Example
The following example contains an invalid "Start address".
Query
BYTE Contents
Example
1
Slave address
0B
2
Function
01
3
Start address high
0D
4
Start address low
FF
5
Data high
FF
6
Data low
01
7
LRC
The slave's answer contains the function plus 0x80, together with error
code "02", i.e. an invalid address.
Response
BYTE Contents
Example
1
Slave address
0B
2
Function
81
3
Error code
02
4
LRC
