Rockwell Automation 1794-L34 FlexLogix Controller System User Manual - Manual (Page 32)

Publication 1794-UM001G-EN-P - January 2007
32 Communicate over Networks
DF1 slave mode using a controller as a slave station in a master/slave serial
communication network.
When there are multiple slave stations on the network, link slave
stations using modems or line drivers to the master. When you have a
single slave station on the network, you do not need a modem to
connect the slave station to the master. You can configure the control
parameters for no handshaking. You can connect 2 to 255 nodes to a
single link. In DF1 slave mode, a controller uses DF1 half-duplex
protocol.
One node is designated as the master and it controls who has access
to the link. All the other nodes are slave stations and must wait for
permission from the master before transmitting.
User mode
(channel 0 only) communicating with ASCII devices.
This requires your program to use ASCII instructions to read and write
data from and to an ASCII device.
DH-485 communicating with other DH-485 devices multi-master, token
passing network allowing programming and peer-to-peer messaging.
Use this mode: For: