JUMO AQUIS touch P, Interface Description

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5 Noncyclical data exchange
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Declaration of a data structure in the "Single-ID" format
In the IO controller, you need to declare 1 data structure (user-defined "STRUCT variable") as both the
target and the source memory for data exchange packets for incoming and outgoing data exchange
packets. Data exchange packets in the "Single-ID" format have a fixed length of 255 bytes and must be
created with the following structure:
Structure variable for data exchange packets in the "Single-ID" format
Data type Name Explanation
BYTE ID-PLC Sequential numbering for assigning the data exchange packets
from queries and responses
The "ID-PLC" value can be used by the IO controller for sequen-
tially numbering the outgoing data exchange packets. JUMO IO
devices enter the same number in the ID-PLC in the data ex-
change packet of the ensuing response, so that response and
query at the IO controller can be assigned, or so that an error in
the sequence of query and response can be intercepted by suit-
able control structures in the IO controller.
BYTE Outgoing:
DIR
Incoming:
ERROR
With the data structure for outgoing data exchange pack-
ets:
"DIR" is thedata direction for transferring noncyclical data.
The data direction must be specified by the PLC programmer in
the data exchange packet of the query from the IO controller,
and then controls the processing of data in the JUMO IO device.
Encoding:
Value= 1: Writing (from the IO controller to the IO device)
Value= 2: Reading (from the IO device to the IO controller)
With the data structure for incoming data exchange pack-
ets:
The JUMO IO device enters the value "1" into "ERROR", if an
invalid ID was indicated in the query data (outgoing data ex-
change packets). In the IO controller, "ERROR" can be evaluat-
ed via a corresponding control structure.
WORD ID1 5-element ID of the data point from the noncyclical data table
(see chapter 5.2 "Data tables of noncyclical data", page 25)
WORD ID2
WORD ID3
WORD ID4
WORD ID5
ARRAY[243 bytes]
(e.g. REAL, INT, BYTE, or also
an array for strings) VALUE Data point of the noncyclical data with a length of up to243 bytes
to be queried or overwritten;
Value of the data point to be read/written; this variable can be
declared as any data type with a length of 243 bytes (e.g string
arrays).