7
Deployment PtP communication
7.1 Fast introduction
The CPU has a RS485 interface X3, which is fix set to PtP communication (
p
oint
t
o
p
oint).
n
PtP functionality
–
Using the PtP functionality the RS485 interface is allowed to connect via serial
point-to-point connection to different source res. target systems.
The protocols res. procedures ASCII, STX/ETX, 3964R, USS and Modbus are supported.
The parametrization of the serial interface happens during runtime using the FC/SFC 216
(SER_CFG). For this you have to store the parameters in a DB for all protocols except
ASCII.
The FCs/SFCs are controlling the communication. Send takes place via FC/SFC 217
(SER_SND) and receive via FC/SFC 218 (SER_RCV). The repeated call of the FC/SFC
217 SER_SND delivers a return value for 3964R, USS and Modbus via RetVal that con-
tains, among other things, recent information about the acknowledgement of the partner
station. The protocols USS and Modbus allow to evaluate the receipt telegram by calling
the FC/SFC 218 SER_RCV after SER_SND. The FCs/SFCs are included in the consign-
ment of the CPU.
The following FCs/SFCs are used for the serial communication:
FC/SFC
Description
FC/SFC 216
SER_CFG
RS485 parameterize
FC/SFC 217
SER_SND
RS485 send
FC/SFC 218
SER_RCV
RS485 receive
More information about the usage of these blocks may be found in the
manual "SPEED7 Operation List" from VIPA.
General
Protocols
Parametrization
Communication
Overview FCs/SFCs for
serial communication
VIPA System 300S
+
Deployment PtP communication
Fast introduction
HB140 | CPU-SC | 313-5BF23 | en | 19-01
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