Moog ACV with CANopen bus interface
2 Access over CANopen
CANopen communication protocols
B99224-DV018-D-211, Rev. A, October 2018
27
2.8.3.5 TxPDO mapping (COB-ID: 0x180, 0x280, 0x380, 0x480)
With the transmit process data object (TxPDO) mapping the most object dictionary entries can be mapped to
a TxPDO. A CANopen telegram can carry 8 bytes data in one package. The smallest data types used in the
digital servo valve are 8 bit integers. Therefore eight object dictionary entries with 8 bit data length or four ob-
ject dictionary entries with 16 bits or two object dictionary entries with 32 bit can be mapped within one Tx-
PDO. An arbitrary combination of different data types is possible, if the sum of the mapped TxPDO data is
less or equal 8 bytes.
The default PDO mapping for a hydraulic CANopen device is defined in the device specific profile CiA 408.
Example:
The following values should be mapped to the fourth TxPDO (default mapping):
• Device state machine (DSM) Status Word <StatusWord> (0x6041) (sub-index 0x00)
Chapter "5.2 Device state machine (DSM)", page 46
• Spool position actual value <SplActualValue> (0x6301) (sub-index 0x01)
Chapter "7.3 Spool position controller", page 153
• Pressure actual value <PrsActualValue> (0x6381) (sub-index 0x01)
Chapter "7.5.11 Actual value filter", page 174
Figure 8: Transmit process data object (TxPDO) mapping
With the parameter <TPdo4_NumberOfMappedApplicParaInPdo> of the mapping object 0x1A00 the number
of mapped values is defined. The second sub-index contains the reference to the <StatusWord> (0x6041)
(sub-index 0x00) with a combination of index, sub-index and length of the parameter to be used. The refer-
ences to the values <SplActualValue> (0x6301) (sub-index 0x01) and <PrsActualValue> (0x6381) (sub-index
0x01) are done in the same manner.
0x63010110
15
<StatusWord> (0x6041)
0x63810110
<TPdo4_ApplicPara1> (0x1A03)
0x60410001
Digital servo valve
Object Dictionary (OD) /
Parameter
0x60410010
0x...
0x...
0x...
6546
<SplActualValue> (0x6301)
8563
<PrsActualValue> (0x6381)
<TPdo4_ApplicPara2> (0x1A03)
<TPdo4_ApplicPara3> (0x1A03)
TxPDO Header
Status word
Spool position
actual value
Pressure
actual value
Unused
Byte 1
Byte 2
Byte 4
Byte 3
Byte 5
Byte 6
Byte 7
Byte 8
CANopen telegram
0x63010110
0x...
0x...
0x...
0x63801110
0x...
0x...
0x...
3
<TPdo4_NumberOfMappedApplicParaInPdo> (0x1A03)
15
6546
8563
Unused
