Table of Contents
Advertisement
Communications Capabilities
12.5
Communications Link Using the 3964/3964R Communications Protocol
(for CPU 944 with Two Serial Ports Only*)
A communications link enables data interchange between two
CPUs) or between a programmable controller and a remote node (with 3965/3964R line proce-
dure). A communications link is possible over interface SI 2 only.
The CPU's application program initiates data interchange, which is then controlled by the 3964
(3964R) line procedure. In contrast to the 3964, the 3964R line procedure generates a block check
character (BCC) at the end of each frame, and transmits this character together with the frame.
The BCC is the vertical parity of all identically-weighted bits in a frame.
The following configurations are feasible (Figure 12-15):
CPU
944
SI 2
Direct line as shown in Figure 12-6 or
two BT 777 transceivers (SINEC L1)
CPU
944
See Figure 12-16
CPU
944
CPU
944
See Figure 12-17
Figure 12-15. Communications Link between a CPU 944 with Two Serial Ports and a Remote Node
*
With operating system submodule 816-1BB21
12-38
SI 1
CPU
941-
944
Other node
programmable controllers (two
CPU
944
CP
E.g. with special driver S5 R006,
524
"Programmable Computer Link
(525)
with 3964/3964R Protocol without
response message frame"
(Order No.: 6ES5 897-2AB11-03)
CP
523
S5-115U Manual
EWA 4NEB 811 6130-02b
Advertisement
Table of Contents
