Memory Organization - Siemens SINUMERIK 840D sl Function Manual

M3: Coupled axes
5.2 Curve tables
Selection of memory type
While defining a curve table, it can be defined whether the curve table is created in the static
or dynamic NC memory.
Note
Table definitions in the static NC memory are available even after control system run-up.
Curve tables of the dynamic NC memory must be redefined after every control system run-
up.
5.2.3

Memory organization

Memory configuration
The storage place available for the curve table in the static and dynamic NC memory is
defined during memory configuration ( → refer to Commissioning / Memory Configuration).
Memory optimization
In a curve table with linear segments, the linear segments can be stored efficiently in the
memory only if the two following machine data are > 0:
MD18403 $MC_MM_NUM_CURVE_SEG_LIN (number of linear curve segments in the static
NC memory)
MD18409 $MC_MM_NUM_CURVE_SEG_LIN_DRAM (number of linear curve segments in
the dynamic NC memory)
If no memory areas are created with this machine data, then the linear segments are stored
as polynomial segments.
Alarm in case of insufficient memory
If memory has been configured for tables with linear and polynomial segments via machine
data and memory for linear segments runs out when generating a linear table, the the
memory for polynomial segments is used for the linear segments (if available). In this case,
memory is "wasted", as a polynomial segment requires an unnecessary amount of memory to
store a linear segment. This circumstance is conveyed through an alarm, which also
discloses the number of unnecessarily used polynomial segments. The alram only displays
awarning and does not result in the interruption of the program or the generation of the curve
table.
If a curve table consists of linear segments and polynomials of a high degree, a memory area
for linear segments and a memory area for polynomial segments is required for the storage of
the curve table. An alarm is output if insufficient memory is available in the relevant areas.
The alarm parameters can be used to detect the resources that are insufficient.
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Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Special Functions