Jetter JetWeb JX2-PR0FI1, Руководство оператора

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JX2-PROFI1 6 Description of Operations
44 Jetter AG
6 Description of Operations
6.1 Buffer Configuration
Data exchange between the user program and the PROFIBUS master is carried out
via input and output registers. Each of these registers contains a data word of 16 bit.
In order to keep the user program as flexible as possible, the memory area, to which
this registers are to belong, is freely selectable. Two registers have been made
available for this purpose. One register contains the start address of the respective
memory area, the other register contains the number of data registers. This way, the
input data starting from register 1m300, for example, and the output data starting
from register 1m400, can be positioned.
As up to 122 input registers can be used, the memory areas would overlap in a
configuration as the one described above. In order to avoid this, the configuration of
the buffers can now be altered as well. The sketch below is to illustrate the interplay
of the registers:
Fig. 7: Structure of the input and output buffers
The address range of registers 1m300 through 1m999 is freely available to the user.
The data buffers can be freely distributed within this range. Letter m stands for the
module number, which is dependent on the configuration of the controller.
The buffers may only be configured during the initialization phase. Under any other
circumstances, the structure of the buffers cannot be changed. This is to keep the
user from making access to a register which has not been defined.
When the user alters one of the buffer configuration registers, a check-up will be
made to ensure that the changed buffer configuration is correct. Among other
features, overlapping of various ranges and exceeding the permitted maximum
widths will be checked. In case an error has occurred in this process, it will be
displayed both in the error register 1m134 and in the error LED.
10
1m309
.
.
.
1m300
Register 1m102
Width of the Input Data
10 Register 1m103
Width of the Output Data
300 Register 1m112
Address of the Input Data
400
Register 1m113
Address of the Output Data
xxxx
.
.
.
xxxx
1m409
.
.
.
1m400
xxxx
.
.
.
xxxx