88 • CANopen
Network
Communication
WAGO-I/O-SYSTEM
750
CANopen
4.3.1.2.1.3 Upload SDO Protocol
This protocol is used to read data out of the bus coupler.
4.3.1.2.1.3.1
Initiate SDO Upload
The data transmission from the bus coupler to the master is initiated with this
protocol. When transmitting data of max. 4 bytes, these are also transmitted
within the protocol.
Client
Client
Initiate SDO Upload
Initiate SDO Upload
reserved
Data
ccs = 2
scs = 2
x
x
n
e
m
m
s
request
confirm
indication
response
0
0
.0
.0
.7
.7
.6
.6
.5
.5
.4
.4
.3
.2
.3
.2
.1
.1
1
1
4
4
8
8
Server
Server
Fig. 4-6: Initiate SDO Upload
g012410x
ccs:
Client command specifier
2: initiate upload request
scs:
Server command specifier
2: initiate upload response
n:
is only valid if e = 1 and s =
1, otherwise 0.
If n is valid, it displays the number of bytes in d
which do not contain any data. The bytes [8-n, 7]
do not contain segment data.
e:
transfer type
0: normal transfer, number of bytes to be written
>= 5 bytes
1: expedited transfer, number of bytes to be
written < 5 bytes
s:
size indicator
0: the number of bytes to be transmitted is not
displayed
1: the number of bytes to be transmitted is dis-
played (depending on the number of bytes)
m:
multiplexor
Index and sub-index of the object directory:
Index, Low Byte : Byte #1
Index, High Byte: Byte #2
Sub-Index: Byte #3
