JVL MAC050 User Manual page 261

5.7 Expansion Module MAC00-FD4
5.7.19 Examples - Typical needed actions in a DeviceNet system.
A number of typical actions is often needed in a system with DeviceNet interface to per-
form the desired operation in the system.
This chapter have some important guidelines on how to handle these typical actions and
issues.
Addressing registers in the motor using explicit messaging and I/O-messages.
Although the basic positioning handling is done using the standard Position controller
specified from the ODVA organisation it is sometimes necessary to access the registers
directly. This section covers the various ways of doing this on top of a more thorough
explanation on the different data formats. For a general motor register overview please
consult
Register addressing in the motor:
To access the registers in the motor there are 2 ways of doing this. Either use explicit
messages or the I/O message approach.
Explicit register access:
To access the registers in the motor explicit (not cyclic), use the object 0x64 with the
instance number as a reference to the register number and the attribute as the
amount of bytes that needs to be handled.
Example: The velocity of the motor needs to be set. In order to do this the velocity
register (register 5 named "V_SOLL") must be used.
To setup the explicit message, setup the following parameters as follows:
Object 0x64
Instance: 5 (register 5, V_SOLL register)
Attribute 1: Data (for write operation)
Attribute 2: Bytes (write operation)
I/O-message access (cyclic transmission):
To gain access to the motor registers directly using the I/O-message approach simply use
the command message type 0x1F. Please see
tails concerning the 0x1F message frame.
JOG function.
Often it is necessary to run the motor a certain distance in positive or negative direction
in order to find a certain reference point or similar.
The MAC motor can be controlled in several different modes. Typically used modes are
"Position" -mode for positioning purpose or "Velocity" -mode which control the motor
movement without taking any notice of the actual position.
If a JOG function is needed it is strongly recommended to use the velocity mode since
the position mode or related modes involves a number of registers and is more complex
compared to the velocity mode.
In velocity mode, none of the position related registers are of particular interest but the
actual position counter is still updated continuously.
JVL A/S - User Manual - Integrated Servo Motors MAC050 - 4500
MacTalk communication, page 402.
IO-messages., page 250 in order to see de-
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