ABB Protronic 100, Руководство пользователя

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Operation 15
Description of the acyclic READ service in accordance with DP V1
The acyclic READ service hands over 3 parameters: -
Request telegram:
Table 1
Positive response telegram:
Table 2
Negative response telegram:
Table 3
Parameter
name Value range Data type Description
Slot 0 - 254 Byte Slot for addressing the
variable to read
Index 0 - 254 Byte Index for addressing the
variable to read
Length 1 - 240 Byte Number of bytes to read
Parameter
name Value range Data type Description
Length 1 - 240 Byte Number of read bytes. If the
required length for the data is
inferior to the length in the
request, the smaller value is
entered here. If the required
length for the data is superior
to the length in the request,
the value of the request is
entered here. ---
Data ...... Byte Bytes for required size. The
number of bytes corresponds
exactly to the specified
length. -
Parameter
name Value range Data type Description
Error
ID ...... Byte Provides information about
the sending protocol system
(here PROFIBUS-DP V1). -
The only valid value that may
appear here is 128.-
Error code 1 ...... Byte Error details. ID:-
0xA0 Variable defined by
slot and index is
unknown. -
0xA8 Controller firmware
does not support
PROFIBUS-DP
V1.-
0xB0 Service not yet
usable.-
0xC0 Too many requests
at the same time.
Current request will
not be processed. -
-
Error code 2 ...... Byte Not used