CANopen Programmer's Manual - Maccon.de

1: Introduction CANopen Programmer’s Manual
How to Map (or Remap) a PDO
Process Overview
Two objects in the device’s object dictionary define a PDO:
A PDO’s communication object defines the PDO’s CAN message ID and its communication
type (synchronous or asynchronous) and triggering type (event-drive or cyclic).
A PDOs mapping object maps every data byte in the PDO message to an object in the
device’s object dictionary.
Mapping a PDO is the process of configuring the PDO’s communication and mapping objects.
To Map a Receive PDO
The general procedure for mapping a receive PDO follows. (The procedure for mapping a transmit
PDO is similar).
Stage Step Sub-steps/Comments
1 Disable the PDO. In the PDO’s mapping object (Receive PDO Mapping Parameters, index
0x1601), set the sub-index 0 (NUMBER OF MAPPED OBJECTS) to zero.
This disables the PDO.
2 Set the communication
parameters.
If necessary, set the PDO’s CAN message ID (PDO COB-ID) using subindex
1 of the PDO’s RECEIVE PDO Communication Parameters (index
0x1401).
Choose the PDO’s transmission type (PDO TYPE) in sub-index 2 of
object 0x1401. A value in the range
[0-240] = synchronous; [254-255] = asynchronous.
3 Map the data. Using the PDO’s mapping parameters (sub-indexes 1-4 of Receive PDO
Mapping Parameters, index 0x1601), you can map up to 4 objects (whose
contents must total to no more than 8 bytes), as follows:
4. Set the number of mapped
objects and enable the PDO.
In bits 0-7 of the mapping value, enter the size (in bits) of the object to be
mapped, as specified in the object dictionary.
In bits 8-15, enter the sub-index of the object to be mapped. Clear bits 8-
15 if the object is a simple variable.
In bits 16-31, enter the index of the object to be mapped.
In the PDO’s Receive PDO Mapping Parameters (index 0x1601), set subindex
0 (NUMBER OF MAPPED OBJECTS) to the actual number of
objects mapped. This properly configures the PDO. Also, the presence of
a non-zero value in the NUMBER OF MAPPED OBJECTS object enables
the PDO.
28 Copley Controls