126 Communication protocol
Read Service (SDO Upload)
Initiate SDO Upload Protocol
This protocol is used to implement the Initiate SDO Upload service.
Client
Request
0
Confirm
scs = 2
ccs
Client command specifier; ccs = 2: Initiates the upload request.
scs
Server command specifier; scs = 2: Initiates the upload
response.
n
Number of data bytes (in d) which do not contain data. Bytes
[8-n, 7] do not contain segment data. Valid only if e = 1 and s =
1 (otherwise n = 0).
e
Transfer type; e = 0: Normal transfer. e = 1: Expedited transfer.
s
Size indicator; s = 0: No data set size indication.
s = 1: Data set size indication.
m
Multiplexor; represents the index/subindex of the data to be
transferred by the SDO.
d
Data; e = 0, s = 0: Reserved for further use.
e = 0, s = 1: Contains the number of bytes to be uploaded.
Byte 4 contains the LSB and byte 7 contains the MSB.
e = 1, s = 1: Contains the data of length 4-n to be uploaded.
Encoding depends on the type of the data referenced by index
and subindex.
e = 1, s = 0: Contains unspecified number of bytes to be
uploaded.
x
Not used. Value is always 0.
Reserved Reserved for further use. Value is always 0.
Initiate SDO Upload Protocol
0
1
7...5
4...0
ccs = 2
x
7...5
4
3...2
1
x
n
e
4
Reserved
m
1
4
0
m
s
Server
8
Indication
8
Response
d