BUDE_Manual-CANopen_EN.doc
13/55
Baumer Hübner GmbH
23.10.2012/bja
Berlin, Germany
Cyclical (asynchronous)
If you wish the PDOs to be transmitted cyclically, the value FEh must be written into the object 1800h /
1801h Subindex 2. In addition, the cycle time in milliseconds must be entered in the same object Subindex 5.
The entered time is rounded off to 1 ms. If the value is stored for 0 ms, the PDOs are not transmitted. The
function is switched off.
The object 2800h / 2801h offers another possibility: If the value is 0, cyclical transmission runs as described
above. If the value is 1, a cyclical test is performed as to whether a change of the value has occurred. If not,
no transmission takes place. If the value is 4, the PDO is transmitted four times with each cycle if there is a
change.
Overview
In the following table, the different transmission modes for PDOs are summarized:
1800h
2800h
Summarized description
Sub2
Sub5
FEh
3ms
0
Cyclical transmission every 3 ms
FEh
5ms
2
Every 5 ms, the PDO is sent twice if there is a change
FEh
0ms
0
Transmit PDO switched off
FEh
0ms
xxx
Transmit PDO switched off
3
xxx
0
Transmit with every third sync telegram
3
xxx
2Bh
On every third sync telegram, but only 43 times in total (=2Bh).
PDO (Position)
PDO1 telegram structure:
ID
DLC
Byte 1
Byte 2
Byte 3
Byte 4
181h
4
xx
xx
xx
xx
ID
: 180h + node ID
Length
: 4 DataByte
Byte1 - 4
: Current position in increments
PDO2 telegram structure:
ID
DLC
Byte 1
Byte 2
Byte 3
Byte 4
281h
4
xx
xx
xx
xx
ID
: 280h + node ID
Length
: 4 DataByte
Byte1 - 4
: Current position in increments
