5 basic features implemented by canopen, 6 response to busoff communication faults, 7 system requirements – BECKHOFF AX2000 CANopen communication profile User Manual
Page 9: 8 transmission rate and procedure, Basic features, Communication faults, Data transfer functions, Positioning functions, Setup functions, System requirements

1.5
Basic features implemented by CANopen
When working with the position controller that is integrated in AX2000/2500 digital servo amplifiers,
the following functions are available:
Setup and general functions:
—
homing, set reference point
—
jogging, with a variable speed
—
provision of a digital setpoint for speed and torque control
Positioning functions:
—
execution of a motion task from the motion block memory of the servo amplifier
—
execution of a direct motion task
—
absolute trajectory
Data transfer functions:
—
transmit a motion task to the motion block memory of the servo amplifier
A motion task consists of the following elements:
» position setpoint (absolute task) or path setpoint (relative task)
» speed setpoint
» acceleration time, braking time, rate-of-change/jolt limiting (in preparation)
» type of motion task (absolute/relative)
» number of a following task (with or without pause)
—
read a motion task from the motion block memory of the servo amplifier
—
read actual values
—
read the error register
—
read the status register
—
read/write control parameters
1.6
Response to BUSOFF communication faults
The communication fault BUSOFF is directly monitored and signaled by Level 2 (CAN controller).
This message may have various causes.
A few examples:
—
telegrams are transmitted, although there is no other CAN node connected
—
CAN nodes have different transmission rates
—
the bus cable is faulty
—
faulty cable termination causes reflections on the cable.
A BUSOFF is only signaled by the AX2000/2500 if another CAN node is connected and at least one
Object was successfully transmitted to start off with. The BUSOFF condition is signaled by the error
message F23. If the output stage is enabled for the execution of a motion task at the moment when
this fault occurs, then the drive is braked to a stop, using the emergency stop ramp, and the output
stage is disabled.
1.7
System requirements
—
servo amplifier AX2000/2500
—
master station with a CAN-bus interface (e.g. PC with CAN interface)
1.8
Transmission rate and procedure
—
bus connection and bus medium: CAN-standard ISO 11898 (CAN high-speed)
—
transmission rate: max. 1Mbit/s
possible settings for the servo amplifier:
10, 20, 50, 100, 125, 250, 333, 500 (default), 666, 800, 1000 kbit/s
CANopen for AX2000/2500
9
BECKHOFF
07/2007
General