7 — CANopen COMMUNICATIONS
pg. 39
Curtis Model 3150R – Oct. 2022
Transmit Messages
Block SDOs are used to transmit messages. A message is displayed after the transfer is ended. The
following example describes how to transmit the message for the example in the Format Messages
section. The example uses 50h as the message center node ID:
Node ID
Data Bytes (hexadecimal)
Description
0
1
2
3
4
5
6
7
0x650
2F
21
70
00
01
00
00
00
Client enables the message center.
0x650
C2
20
70
00
52
00
00
00
Client initiates block download.
0x5D0
A0
20
70
00
7F
00
00
00
Server acknowledges download request.
0x650
01
49
6E
66
6F
72
6D
61
Client transfers segment 1.
0x650
02
74
69
6F
6E
3A
2F
58
Client transfers segment 2.
0x650
03
32
30
59
36
30
46
31
Client transfers segment 3.
0x650
04
43
34
2F
53
70
65
65
Client transfers segment 4.
0x650
05
64
3A
2F
58
31
32
30
Client transfers segment 5.
0x650
06
46
30
43
31
2F
31
32
Client transfers segment 6.
0x650
07
6B
6D
2F
2F
68
2F
58
Client transfers segment 7.
0x650
08
32
30
59
31
32
30
46
Client transfers segment 8.
0x650
09
31
2F
46
61
75
6C
74
Client transfers segment 9.
0x650
0A
3A
2F
58
31
32
30
43
Client transfers segment 10.
0x650
0B
32
2F
32
2C
33
2F
46
Client transfers segment 11.
0x650
8C
30
2F
5B
31
5D
00
00
Client transfers the final segment.
0x5D0
A2
0C
7F
00
00
00
00
00
Server acknowledges the final segment.
0x650
C9
00
00
00
00
00
00
00
Client requests to disconnect.
0x5D0
A1
00
00
00
00
00
00
00
Server confirms the disconnection and the
device displays the message.
Clear Messages
Clearing a message removes the message and restores the message center’s default formatting. To
clear a message, set the 8 bit object with an index and sub-index of
0x7023:00
to 1h.