Parameter Assignment - Siemens SINUMERIK 840D sl Function Manual

Parallel data access
A parallel read access through compile cycles and part programs/synchronous actions on
data of the same I/O range is possible, as long as the corresponding I/O range has been
configured for this. One must ensure that the read accesses have access to the different
mappings of the PROFIBUS-I/O data. The data consistency within these mappings is
ensured. However, the data equality between these mappings cannot be ensured during an
IPO cycle.
A parallel writing access through compile cycles and part programs/synchronous actions on
data of the same I/O range is not possible. While configuring the NCK it must be determined,
whether a specific I/O range of the PROFIBUS-I/O is allocated to the system variables or to
the compile cycles.
Activation
The function is activated during the NCK-ramp up.
1.3.2

Parameter assignment

The configuration of the I/O range is done via the machine data. The parameters once set
can no longer be changed during the normal operation of the NCK.
16 I/O ranges in the read direction and 16 I/O ranges in the write direction are provided. NCK
restricts the maximum size of the I/O ranges to 128 bytes each.
Once an I/O range is activated its availability is checked each time an IPO cycle starts. For
this, the lifespan of a useful-data slot within an I/O range is evaluated. If the lifespan is not
set at the start of an IPO cycle, an alarm (9050 or 9052) is issued. This alarm does not stop
the processing of the part program, but instead is only displayed and remains as such till the
affected I/O range gets a valid lifespan again.
Logical start address
To make specific I/O ranges available again, their logical start addresses must be conveyed
to the NCK. To do this, the following machine data must be configured:
MD10500 $MN_ DPIO_LOGIC_ADDRESS_IN[n]
MD10510 $MN_ DPIO_LOGIC_ADDRESS_OUT[n]
Length of an I/O range
In order that the NCK can check, whether an I/O range has been configured completely, the
expected length (bytes) of the corresponding I/O range must be entered. To do this, the
following machine data must be configured:
MD10501 $MN_ DPIO_RANGE_LENGTH_IN[n]
MD10501 $MN_ DPIO_RANGE_LENGTH_OUT[n]
If the length "0" is entered, only the useful-data slot found under the corresponding logical
start address is configured as I/O range. In such a case, the length of the I/O range is then
compared with the length of the useful-data slot found.
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
A4: Digital and analog NCK I/Os
1.3 NCK I/O via PROFIBUS - only 840D sl
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