User manual

Chapter 4 Configuration
MAN_905G_1.16 Page 96
Set Slave Mode
SET_SLAVE_MODE: Command Number = 0003h.
In addition to station related user data transfer, which is executed automatically, the master
can send control commands to a single slave, a group of slaves or all slaves simultaneously.
These control commands are transmitted as multicast commands. This permits use of sync
and freeze modes for event controlled synchronisation of the slaves.
The slaves begin sync mode when they receive a sync command from their assigned master.
The outputs of all addressed slaves are then frozen in their current state. During subsequent
user data transmissions, the output data are stored at the slaves, but the output states remain
unchanged. The stored output data are not sent to the outputs until the next sync command is
received. Sync mode is concluded with the unsync command.
Similarly, a freeze control command causes the addressed slaves to assume freeze mode. In
this operating mode, the states of the inputs are frozen until the master sends the next freeze
command. Freeze mode is concluded with the unfreeze command.
Note : Not all slaves supports this feature. Consult the documentation for the actual slave for
further information.
Command and response layout:
Command Response
Message ID
(ID) (ID)
Message Information
4002h 0002h
Command Number
0003h 0003h
Data Size
0000h 0000h
Extended Word 1
Slave
Address
Group Select Slave Address Group Select
Extended Word 2
Control
Command
- Control
Command
-
Extended Word 3
- -
Extended Word 4
- -
Extended Word 5
- -
Extended Word 6
- -
Extended Word 7
- Extended Fault Info
Extended Word 8
- Fault Information
• Slave Address
Range 1-125; 127
If the request applies for only one slave, that Slave Address must be entered in the range
1-125. If a slave group is to be addressed, Slave Address should be 127 (Multicast
address).
• Group Select
Range 01h -FFh (Bit coded)