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IDENT-I • IVI-KHA6-4HRX, IVI-KHD2-4HRX
Operating control interface units using the 3964R protocol
8.1.5 Data exchange via 3964R with RK512 involving SEND messages
The commands are transmitted in the form of data contained in a SEND message.
Responses to the command received are transmitted to the control system via a
SEND-message. The possible responses to a command are as follows:
• Fixed code command: Codes, error messages
• Read/write commands: Data, error messages, negative acknowledgment of a write
command
• Operating mode commands: Positive or negative command acknowledgment
The message parameters in the response message are obtained from the initializing
SEND message. This gives the user the opportunity to place the required data in the
appropriate address space. The following parameters are required from the initializing
SEND message:
Parameter
Number of target data block
Start address in target data block
CPU number
Coordination marker
The only restriction is in relation to the data type. The data can be transmitted in a
single data block only. Accordingly, send and receive data are organized in words. If
the selected data format has a data length consisting of an odd number of bytes, a
byte, value 00h, is added. The same applies to the transmission of a command from
the control system to the control interface unit.
Example:
Communication errors or errors relating to the message structure are transmitted in
the 4th character of the response message.
Value
0Ch
10h
14h
34h
36h
Bild 8.7:
Error numbers for message errors
8.1.6 Data exchange without the RK512 Interpreter
The command and data structure are the same as when using the protocol with the
RK512. The RK512-specific message header and message exchange sequence are
not used.
Subject to reasonable modifications due to technical advances.
40
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 7 79 90 91 • Internet http://www.pepperl-fuchs.com
"Double-sided" read command
Data transmitted to the control interface unit: 02 00
Significance
The data type specified is not valid
Bytes 1 and 2 of the message were not 00h
The data block specified is not permissible
The quantity of data sent was incorrect
Incorrect message sequence
Permissiblerange
3 ... FFh
0 ... FFh
any
FFFFh
Copyright Pepperl+Fuchs, Printed in Germany
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