
3 Protocol description
15-04-2016 18 7000.05052
3.3.2
Segmented transfer
3.3.2.1
SDO Block Upload
The segmented SDO block upload protocol is based on CiA301.
Fig. 6: Sequential diagram for the SDO block upload
1) This is repeated until less than 58 bytes remain to be transmitted
Tab. 7: Request SDO Initiate Block Upload (Master to Slave)
Byte
Contents
Description
1
7
User data length 7 bytes
2
Node number
Node number
3
0x08
Command SDO Block Read Init
4
Index LB
Index of the object entry LB
5
Index HB
Index of the object entry HB
6
Sub-index
Sub-index of the object entry
7
CRC
Check sum
Master
Slave
SeqNr = 0
[dataLen > 110]
Request_SDOBlockReadInit(Index, Subindex)
Acknowledge_SDOBlockReadUpload(AckSeq)
Response_SDOBlockReadUpload(SeqNr, Data)
Request_SDOBlockReadUpload()
Response_SDOBlockReadInit(Index, Subindex, Data)
Acknowledge_SDOBlockReadEnd(AckSeq)
Response_SDOBlockReadEnd(Seqnr, Data)
t
s
optional
SeqNr ++
(1)