5 Noncyclical data exchange
24
CAUTION!
The data exchange packets have a predefined format.
If the data structures are not filled with fill bytes to the correct length, errors can occur during the data
exchange.
Be sure to respect the data structure defined above (data types, sequence of the variables and total
length, including fill bytes) when declaring the data structures for data exchange packets.
BYTE DIR_1
a
Query/re-
sponse data
for data
point 1
Data for transferring up to 4 data points of
noncyclical data; the following variables are
declared for each data point:
DIR: Data direction for transferring the respec-
tive data point;
The data direction of each data point must be
specified by the PLC programmer in the data
exchange packet of the query from the IO con-
troller. The "DIR" variables control the process-
ing of the single data points in the JUMO IO
device accordingly.
Coding:
Value = 1: Write (from IO controller to IO de-
vice)
Value = 2: Read (from IO device to IO control-
ler)
ERROR:
Data structure for incoming data exchange
packets:
In case of "ERROR", the JUMO IO device en-
ters an integer value as error indicator. In the
IO controller, "ERROR" can be evaluated via a
corresponding control structure.
List of error values:
chapter 7 "Error messages", Page 57
ID1 to ID5: 5-element ID of the respective data
point from the noncyclical data table
chapter 5.2 "Data tables of noncyclical da-
ta", Page 36
VALUE: Value to be read/written of the respec-
tive data point; this variable must always be de-
clared as a basic data type with a length of 32
bits. If the query aims at an IO device data type
with 16 or 8 bits, only the corresponding lower-
value bytes are relevant. The higher-value
bytes are to be considered pure fill bits.
BYTE ERROR_1
a
WORD ID1_1
a
WORD ID2_1
a
WORD ID3_1
a
WORD ID4_1
a
WORD ID5_1
a
Any basic data type with a
length of 32 bits
VALUE_1
a
.
.
.
.
.
.
Query/re-
sponse data
for data points
2 and 3 with
identical struc-
ture
BYTE DIR_32
a
Query/re-
sponse data
for data point 4
BYTE ERROR_32
a
WORD ID1_32
a
WORD ID2_32
a
WORD ID3_32
a
WORD ID4_32
a
WORD ID5_32
a
Any basic data type with a
length of 32 bits
VALUE_32
a
a
In the "Multi-ID" format, all variables are declared and also transferred for 4 data points.
Structure variable for data exchange packets in the "Multi-ID" format
Data type Name Explanation
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