MOVIDRIVE
®
DFC11A CAN Bus
19
Parameter Setting via
CAN Bus
4
Fig. 15 shows the structure of the parameter message. It generally consists of a management byte,
an index word, a reserved byte and four data bytes.
MD0230AE
Fig. 15: Structure of the parameter message
4.1.1.1 Management of the Parameter Message
The entire parameter adjustment sequence is co-ordinated using byte 0: Management. This byte
provides important service parameters such as Service Identifier, data length, execution and status
of the executed service. Fig. 16 shows that bits 0 to 3 contain the Service Identifier, in other words
they define which service is to be executed. Bits 4 and 5 specify the data length in bytes for the
WRITE service, which in the case of SEW drive inverters should generally be set at 4 bytes.
Handshake bit 6 = 0:Asynchronous response to the Synchronization message
Handshake bit 6 = 1:Synchronous response to the Synchronization message in the first millisecond.
Status bit 7 indicates whether the service was executed properly or whether it produced a fault. .
01027AEN
Fig. 16: Structure of the management byte
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
Byte 7
Management
Management
Reserved
Reserved
Index High
Parameter index
Index Low
Data MSB
Data
Data
Data LSB
4-byte data
7
6
5
4
3
2
1
0
Bit:
MSB
LSB
Byte 0: Management
Service identification:
0000 = No service
0001 = Read parameter
0010 = Write parameter
0011 = Write parameter volatile
0100 = Read Minimum
0101 = Read Maximum
0110 = Read Default
0111 = Read Scale
1000 = Read Attribute
Data length:
00 = 1 byte
01 = 2 bytes
10 = 3 bytes
11 = 4 bytes
Handshake mode bit
0 = asynchronous, send Response immediately
1 = synchronous, send Response upon receipt of
SYNC message
Status bit
0 = Performance of service o.k.
1 = Performance of service faulty