Compatible Host Devices; Communication Connections - Allen-Bradley 1779-KFMR User Manual

Chapter 2
Introducing the 1779 KFM Interface

Compatible Host Devices

Communication Connections

2 4
Figure 2.3
A Computer Communicating with Other Nodes through a 1779 KFM Interface
Host Device
Synchronous
RS 422/449
Compatible
Computer
The 1779-KFM interface is compatible only with host devices that have
the following attributes:
The host device must provide HDLC link-layer protocol.
The host device must communicate through a port compatible with both
the RS-422 and RS-449 standards.
The host device must provide synchronization signals as the data
terminal equipment (DTE) device on the link. The 1779-KFM is the
data circuit-terminating equipment (DCE) device.
To communicate with the 1779-KFM interface in a Native-mode
message set, the host device must be a programmable device, such as a
computer.
The 1779-KFM interface communicates through connectors on its front
surface (Figure 2.4).
The RS-449 CHANNEL connector provides cable connection to the host
computer.
The DATA HWY II jack provides dropline cable connection to a tap on a
Data Highway II link. A redundant 1779-KFMR interface has a second
DATA HWY II jack for a redundant set of cabling for the link.
Your Data Highway II cable redundant interface module
(Cat. Nos. 1779-KFLR, -KFMR, -KP2R, -KP3R) has a connector on the
front panel labeled DHII AUX ACCESS. This connector is for future use.
Do not connect any cable to this connector.
1779 KFM Interface
Power Supply
Board
Host Media
Board Access
Board
Other Nodes
of the
Data Highway II
Communication
Link