Siemens SIMATIC S7-200 - Application; Design; Operation

S7-200 Specifications
A-86
S7-200 Programmable Controller System Manual
A5E00066097-02
Overview
The CP 243-2 is the AS-Interface master for the S7-200 CPU 22x series. The new
communications processor has the following functions:
• Up to 31 AS-Interface slaves can be connected.
• Supports all AS-Interface master functions.
• Status displays of operating statuses and display of readiness of connecting
slaves by means of LEDs in the front plate.
• Error displays (including AS-Interface voltage error, configuration error) by
means of LEDs in the front plate.
• Compact casing in the design of the innovative SIMATIC S7-200 generation.
Application
The CP 243-2 is the AS-Interface master connection designed exclusively for the
S7-200 CPU 22x. Connection to the AS-Interface significantly increases the
number of available digital inputs and outputs for S7-200 (maximum 124 DI/124
DO on AS-Interface per CP). Up to two CP 243-2 can be operated on the S7-200
at the same time.
Design
The CP 243-2 is connected to the S7-200 in the same way as an expansion
module. It has:
• Two terminal connections for direct connection of the AS-Interface cable.
• LEDS in the front plate to display the status and readiness of all connected and
activated slaves.
• Two buttons to display the status information of the slaves, to switch operating
mode and to adopt the existing configuration as the SET configuration.
Operation
In the process image of the S7-200, the CP 243-2 occupies a digital input byte
(status byte), a digital output byte (control byte), and 8 analog input and 8 analog
output words. Therefore the CP 243-2 takes up two logical module positions. The
status and the control byte can be used to set the mode of the CP 243-2 via a user
program. Depending on its mode, the CP 243-2 stores either the I/O data of the
AS-Interface slave or diagnostics values, or enables master calls (e.g. changing a
slave address) in the analog address area of the S7-200.
All the connected AS-Interface slaves can be configured at the touch of a button.
Further configuration of the CP is not necessary.