RS-485 gateway
Contents
1 Preliminary note � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
2 Safety instructions � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
3 Documentation� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
4 Functions and features � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
4�1 Receiving data via the RS-485 gateway � � � � � � � � � � � � � � � � � � � � � � � � � � 4
4�2 Sending data via the RS-485 gateway � � � � � � � � � � � � � � � � � � � � � � � � � � � � 4
5 Manufacturer-specific device behaviour � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 5
5�1 Status model (Root Device Profile) � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 5
5�2 Status transition table� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 5
6 Acyclic CTT2 services� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 6
6�1 Standard services� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 6
6�1�1 Standard ID object � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 6
6�1�2 Standard diagnostic object� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 7
6�2 Exchange device parameters� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 8
6�3 Exchange serial data � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 9
6�4 Data structures � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 10
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RS-485 gateway
1 Preliminary note
This document applies to the device AC1155�
This document is intended for specialists� These specialists are people who are
qualified by their appropriate training and their experience to see risks and to
avoid possible hazards that may be caused during operation or maintenance of
the device� The document contains information about the correct handling of the
device�
Read this document before use to familiarise yourself with operating conditions,
installation and operation� Keep this document during the entire duration of use of
the device�
Adhere to the safety instructions�
2 Safety instructions
UK
These instructions contain texts and figures concerning the correct handling of the
device and must be read before installation or use�
Observe the operating instructions� Non-observance of the instructions, operation
which is not in accordance with use as prescribed below, wrong installation or
incorrect handling can seriously affect the safety of operators and machinery�
3 Documentation
This documentation relates to the hardware and firmware status at the time of
editing this manual�
4 Functions and features
The devices have been designed for use in applications described in this manual
and the data sheet�
Adhere to the data indicated in the data sheets and in the manual� If the handling
specifications and safety instructions for configuration, installation and operation
indicated in the documentation are adhered to, the devices normally do not lead to
any danger for persons and objects�
The AS-i / RS-485 gateway is a slave for the AS-Interface fieldbus system� It
corresponds to the V3�0 specification and can be operated in the extended
addressing mode�
● AS-i profile S-B�A�5, the CTT2 communication protocol is implemented�
The AS-i / RS485 gateway is used to connect devices with an RS485 interface
(text displays, code readers, measurement devices����) to AS-Interface�
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RS-485 gateway
Parameter data is stored permanently in the slave memory� Since the
process of storing takes several 100 ms, the CTT2 communication will stop
and resume after a reset of the device only�
4.1 Receiving data via the RS-485 gateway
The slave cyclically transmits the number of bytes that have been received and
that are available for reception via AS-Interface� The receive buffer in the slave has
a size of 64 bytes�
The master should then send "18, 3, xx" (acyclic read service request to index 3
with a usable length of xx bytes) to collect the information�
If more than 32 bytes are in the buffer, the command may be issued several times
with a maximum length of 32 bytes until the buffer is empty� If there are fewer
bytes in the buffer than required, the response contains all available bytes� If an
acyclic read service request to index 3 is issued while the buffer is empty, the
response is an error "illegal length"�
If single bit transmission errors occur, AS-Interface will repeat faulty telegrams and
recover lost information� If byte transmission errors occur, the data may be lost�
4.2 Sending data via the RS-485 gateway
The master sends "19, 3, xx, ��� data���" (acyclic write service request to index 3
with a usable length of xx bytes) to transmit the output information�
If more than 32 bytes are to be transmitted, this write service may be repeated
several times with a maximum length of 32 bytes� Since the RS-485 interface is
faster than AS-Interface, there is no danger of buffer overrun�
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