Lika IF55 ROT CB, Руководство пользователя

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IF55 ROT CANopen®
6.7 SDO objects
SDO messages are used to set and read values from the Object dictionary of the
Slave device. These parameters are described in the “Object dictionary” section
(see on page 46).
4 bytes at the most are used for CAN data, other 4 bytes are used for Command,
Index and Sub-index fields. SDO messages are always followed by confirmation.
Thus when the Master sends an SDO message to the Slave, then the Slave
always sends a reply (and a warning, should an error occur).
Structure of SDO message:
IDENTIFIER from 4 to 8 CAN data bytes
COB-ID(hex) 0 1 2 3 4 5 6 7
F.C. Node-ID Com Index Sub Data
1byte LSB MSB 1byte LSB … … MSB
Com
command
Index
parameter index
Sub
parameter sub-index
Data
parameter value
6.7.1 Command
The command byte contains the type of telegram transmitted to the CAN
network.
Three types of telegram are available:

Set: it is used to send the configuration parameters to a device;

Req: it is used by the Master to read data from a Slave device;

Warnings: they are used by the Slave to send error messages to the Master
(e.g. following a wrong SDO message:
Object does not exist in the object
dictionary , …).
Command COB COB type Data length
22h Set M

S request not spec.
23h Set M  S request 4 bytes
2Bh Set M  S request 2 bytes
2Fh Set M  S request 1 byte
60h Set S  M confirmation 0 byte
40h Req M  S request 0 byte
42h Req S  M reply not spec.
43h Req S  M reply 4 bytes
4Bh Req S  M reply 2 bytes
4Fh Req S

M reply 1 byte
41h Req S  M reply segmented SDO
80h Warning S

M reply 4 bytes
MAN IF55 ROT CB E 1.2.odt 6 - CANopen® interface (DS 406) 45 of 88