Can Communication - IFM Electronic Ecomot100 CANcom III Handbuch

CAN communication

The CAN communication is based on the communication profile CiA-DS 301.
Since there is at present no device profile for CAN modems a communication
protocol based on process data objects (PDOs) was used.
This also offers the possibility to access the radio modem from a controller which
is configured as a CANopen master.
• In the online mode (direct modem connection) freely definable CAN objects
can be transmitted between 2 CANcom units. The CAN data is transmitted in
a transparent way, the transmission rate is limited to 9600 baud maximum by
the GSM network.
• In the CANopen network the radio modem CANcom operates as a slave.
It uses 2 asynchronous PDOs.
PDO 1 serves as a status or command channel for the remote transmission of
data.
Type: CANcom-Status-PDO;
Type: Master-Command-PDO; direction: master → CANcom
PDO2 is used for the actual transmission of the user data blocks and longer sta-
tus/control information (e.g. phone number, network operator, etc.).
Type: CANcom-Data-PDO;
Type: Master-Data-PDO;
• CANcom responds to every correctly received reception PDO (Rec PDO) with a
transmission PDO (Trans PDO).
• The COB IDs of the PDOs can be configured.
• Larger data volumes (data length > 7 bytes) are transmitted in blocks (see "seg-
mented data transmission", page 64).
• The CAN identifier of the synch object can be configured. After a change the
ID is automatically stored non volatilely.
• The radio modem CANcom supports "node guarding".
The CAN identifier of the guard object can be configured and is stored non
volatilely.
• The radio modem CANcom generates an emergency object.
The COB-ID of the EMCY object can be configured.
• CANcom stores the last error occurred.
The error code of the respective emergency object is stored.
For the factory default setting see the "parameter list", page 50
direction: CANcom → master
direction: CANcom → master
direction: master → CANcom
CAN CR310
COM X
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