Siemens SIMATIC CP 340 User Manual

Communication using function blocks
6.8 Technical data of the function blocks
PtP coupling and configuration of CP 340
Manual, 04/2011, A5E00369892-03
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6.8 Technical data of the function blocks
Introduction
Listed below is the technical specifications relating to memory requirements, runtimes,
minimum number of CPU cycles, and system functions used.
Memory requirements
The table below lists the memory requirements of the CP 340 function blocks/functions.
Table 6- 8 Memory requirements of the function blocks/functions (in bytes)
Block Name Version Load memory Work memory Local data
FB 2 P_RCV 2.0 2264 1888 40
FB 3 P_SEND 2.0 1942 1590 40
FB 4 P_PRINT 2.0 2094 1726 44
FB 12 P_RESET 1.0 1454 1170 30
FC 5 V24_STAT 2.0 182 108 2
FC 6 V24_SET 2.0 150 84 2
Minimum number of CPU cycles
The table below describes the minimum number of CPU cycles (FB/FC calls) required to
process a "minimum job" (14 bytes SEND, 13 bytes RECEIVE for the quantity of user data
transported per program cycle). This only applies in centralized operation.
Table 6- 9 Minimum number of CPU cycles
Number of CPU cycles for processing ...
Termination without
error
Termination with error RESET/RESTART
RECEIVE ≥3 ≥ 3 ≥ 4
SEND ≥ 3 ≥ 3 ≥ 4
PRINT ≥ 3 ≥ 3 ≥ 4
V24_STAT 1 - -
V24_SET 2 >> 2 -
Before the CP 340 can process an activated job after the CPU has changed from STOP to
RUN mode, the CP-CPU startup mechanism of the P_SEND or P_PRINT function block
must have been completed. Any requests initiated in the meantime do not get lost. They are
transmitted once the start-up coordination with the CP 340 is finished.
Before the CP 340 can receive a frame in the user program after a change in the CPU mode
from STOP to RUN, the CP-CPU startup mechanism "RCV" must be completed.

Siemens SIMATIC CP 340 Specifications

General

Type	Communications processor
Model	CP 340
Product type designation	CP 340
Supply voltage	24 V DC
Power supply	24 V DC
Operating temperature	0 to 60 °C
Current consumption	150 mA
Temperature Range	0 to 60 °C
Dimensions	40 mm x 120 mm x 120 mm
Weight	0.5 kg

Summary

Product Description

CP 340 Uses and Functionality

Explains the purpose, functionality, and module variants of the CP 340 for data exchange.

Hardware and Software Components for PtP Connection

Lists essential hardware and software components required for establishing point-to-point connections.

Serial Interface Properties

Details technical specifications for RS 232C, 20mA-TTY, and X27 (RS 422/485) interfaces.

Basic Principles of Serial Data Transmission

Transmission Integrity

Covers data integrity aspects for Printer, ASCII, and 3964(R) drivers.

Data Transmission with the 3964(R) Procedure

Details control characters, block checksums, sending, receiving, and error handling for 3964(R).

Data Transfer using the ASCII Driver

Explains ASCII driver use, RS 232C signals, flow control, and end criteria.

Starting up the CP 340

Step Sequence for Commissioning

Outlines the order of operations required for commissioning the CP 340.

Installation and Configuration

Describes integrating, configuring via STEP 7, and assigning parameters to the CP 340.

Mounting the CP 340

Installing and Removing the CP 340

Provides step-by-step instructions for mounting and dismounting the CP 340.

Configuring and Parameterizing the CP 340

Parameterization Options

Lists configuration options for CP 340 variants using STEP 7 or the parameter assignment interface.

Parameterizing Communications Protocols

Explains how to supply CP 340 interface with parameters and configure message texts.

Configuring the CP 340

Explains how to inform the programmable controller about the CP 340's presence and its address.

Managing Parameter Data

Covers saving, downloading, and managing configuration and parameterization data.

Download of Firmware Updates

Provides instructions for updating the CP 340 firmware using HW Config.

Communication using function blocks

Communication via Function Blocks

Explains how communication occurs between CPU, CP 340, and communication partners via function blocks.

Overview of Function Blocks

Lists and describes function blocks (P_RCV, P_SEND, P_PRINT, V24_STAT, V24_SET) for CP 340 communication.

Using Function Blocks for Connecting to Communications Processor

Details using P_SEND and P_RCV for sending and receiving data between S7 and partners.

Using Function Blocks for Outputting Message Texts to Printer

Explains the P_PRINT FB for sending message texts and variables to a printer.

Using Function Blocks for RS 232C Signals

Covers V24_STAT for reading and V24_SET for controlling RS 232C signals.

Diagnostics with the CP 340

Diagnostics Messages of Function Blocks

Diagnostics by Means of Diagnostic Buffer

Connecting Cables

RS 232C Interface Connecting Cables

20mA TTY Interface Connecting Cables

X27 (RS 422/485) Interface Connecting Cables