Siemens SIMATIC Distributed I/O System DP/ASi Link, Руководство пользователя

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C-6
Distributed I/O System DP/ASi Link
EWA 4NEB 710 6055-02b
C.2 Parameterization Data for ASi Slaves
You have to define four bytes for every ASi slave when you assign parame-
ters. These four bytes contain all the data required for an ASi slave and data
exchange with it. You will find the structure of these four bytes for every ASi
slave in Table C-6.
Table C-6 Parameterization data for an ASi slave
Byte A Byte B Byte C
1
Byte D
2
Bits 7 to 4 Bits 3 to 0 Bits 7 to 4 Bits 3 to 0 Bits 7 to 0 Bits 7 to 0
Configura-
tion status Parameters
of ASi
slave ID code of
ASi slave I/O code
of ASi
slave Codification of input
area Codification of output
area
1
If you do not assign any inputs, you must assign FF
H
to byte C.
2
FIf you do not assign any outputs, you must assign FF
H
to byte D.
With the configuration status, you specify whether the ASi slave is contained
in the ASi. The following two values are possible:
8
H
for configured ASi slaves (bits 7 to 4)
0
H
for unconfigured ASi slaves (bits 7 to 4)
Refer to the data sheet of the ASi slaves for the range of values of the param-
eters of the ASi slaves and their significance. The default parameter setting is
0 and applies to all ASi slaves.
The ID code specifies the manufacturer of the ASi slave modules. The stan-
dard ID code is 0 and can be used by all manufacturers. If the ASi slave ex-
pects a different ID code, you can take it from the data sheet for the ASi
slave.
The I/O code characterizes the ASi slave with reference to its inputs and out-
puts. You will find the I/O code in the data sheet for the ASi slave. If you
know the input and output assignment, you can read the I/O code from
Table B-1 in Appendix B.
After performing optimization of the address assignment (refer to Appen-
dix C.3), you can take both the byte number and the number for every ASi
slave from the address space template.
The position of the first input or output bit in the address space template (re-
fer to Fig. C-1) characterizes every ASi slave. The specifications are impor-
tant for the address assignment.
Structure
Byte A – bits 7 to 4
Configuration
status
Byte A – bits 3 to 0
Parameters of
ASi slave
Byte B – bits 7 to 4
ID code
Byte B – bits 3 to 0
I/O code
Bytes C and D –
input and output
areas
Parameterization Message