Control CANopen devices with USBtin

CANopen is a CAN bus protocol and specifies profiles for automation devices. USBtin can be used to control CANopen devices. Plain CAN messages are transmitted to set outputs through a Beckhoff LC5100 CANopen Coupler.

Hardware setup

An USBtin EB is connected to a Beckhoff LC5100 with KL2134 and KL9010. The jumper for the CAN bus termination (120 ohm) on USBtin is set! Dip-swiches on the LC5100 defines the node-id and the baudrate.

Hardware:

Beckhoff LC5100, KL2134, KL9010 and USBtin EB

Start CANopen node

After power-on the green fieldbus led (upper left led) of LC5100 blinks. This indicates the PRE-OPERATIONAL operating state. If the red CAN bus error led blinks, check the CAN bus wires and bus termination!

Transmit the "Start Remote Node" command (ID 0x000, DLC 2, Data: 0x01, 0x00):

t00020100

The commands were tested with USBtinViewer - Open-Source GUI for USBtin:

CANopen start nodes command

After sending the "Start Remote Node" command, the green fieldbus led on LC5100 stops blinking (permanent on) which indicates "OPERATIONAL (RUN)" mode. Now the LC5100 is ready to accept input/output commands.

Check current state of CANopen node

To check the state of the LC5100 a requst telegram with ID 0x700+nodeID can be sent. In this example the nodeID = 1:

r7010

The device responses with the current state. Bit 7 contains a toggle bit, bits 6...0 contains the node state (0x05 = operational state, 0x04 = prepared or stopped, 0x7F = pre-operational state).

CANopen request state

Set digital outputs

The CAN message identifier for setting digital outputs through LC5100 is 0x200+nodeID with the digital states as data payload. Example with nodeID = 1:
Set Bit0:

t201101

Set Bit0 and Bit1:

t201103

Links

Technical Documentation for CANopen Coupler BK5120, BK5110, LC5100

Running CANopen devices from a Pyton script (using USBtin)