Communications Methods; I/O Communications - YASKAWA SGD7S Product Manual

13.2

Communications Methods

The DeviceNet Module supports two types of communications: I/O communications and
explicit message communications.
13.2.1

I/O Communications

This section describes the command messages that are sent from the master device to the
SERVOPACK and the response messages that are returned by the SERVOPACK. These are
required for I/O communications.
Command Format
The following table gives the data format of the command messages sent to the SERVOPACK
from the master device. Command messages consist of 8 bytes. Bytes 0 to 3 have the same
format for all commands. Byte 0 contains command bits. Bytes 4 to 7 store data that depends
on the command assembly code in byte 2.
Bytes Bit 7
0 Enable
1
2
3
4
5
6
7
 Start Trajectory
Use the Start Trajectory bit to start a move operation. A move operation starts when this bit
changes from 0 to 1 for any of the following command assembly codes.
Command
Assembly Code
0x01
0x11
0x12
0x1E
0x1F
*
The value of PnB55 is the end position.
The SERVOPACK detects when this bit is set to 1. The operation will continue even if it is
cleared to 0 during axis travel.
To stop the move operation before it is completed, set the Smooth Stop bit or the Hard Stop bit
to 1.
 Start Block
Use the Start Block bit to start the execution of command blocks stored in the SERVOPACK.
You can change this bit from 0 to 1 to execute the commands in the command blocks that
have been registered in advance. If this bit is cleared from 1 to 0 during execution of the com-
mand blocks, execution of the command blocks will be stopped.
Refer to the following section for details on the command blocks.
13.4.2 Command Blocks on page 13-23
Bit 6 Bit 5
Valid Hard Smooth
Data Stop
Axis Instance
Axis Instance
Data Low Middle Byte
Data High Middle Byte
Command Data
Target position
Continuous motor speed
Origin return type
Alarm clear
(Switch to positioning)*
Bit 4 Bit 3 Bit 2
Direction Absolute/
Stop (V mode) Incremental
Block Number
Command Assembly Code
Response Assembly Code
Data Low Byte
Data High Byte
Operation
Positioning
Continuous operation
Origin return
Alarm clear
Switch to positioning

13.2 Communications Methods

13.2.1 I/O Communications

Bit 1 Bit 0
Start Start
Block Trajectory
13
13-5