Synchronized Action Parameters - Siemens SINUMERIK 840Di sl Function Manual

2.3.3

Synchronized action parameters

Meaning
The variables $AC_PARAM[n] are used for calculations and also as intermediate memory
and can be read and written in synchronized actions.
Definition
Data type: REAL
n: Number of parameters 0 - n
The number of available AC parameter variables for each channel is determined via the
Machine data
MD28254 $MC_MM_NUM_AC_PARAM
fixed.
These parameters exist once in each channel under the same name. $AC_PARAM
parameters are stored in the dynamic memory.
In MD28255 $MC_NUM_AC_PARAM, the maximum value that can be specified is 20000.
One element requires 4 bytes. You must ensure that sufficient memory of the correct type is
available. The memory location for $AC_PARAM[n] can be selected with the machine data
MD28255 $MC_MM_BUFFERED_AC_PARAM with
0: in the dynamic memory (active file system, default)
1: in the static memory (passive file system)
can be selected.
Synchronized action parameters stored in the static memory can be included in the
data backup. See 2.3.7 The parameters are set to 0 on Power On, NC Reset, and End of
Program, . identical start conditions for every part program run.
In addition, for SW 6.3 and higher
In software version 6.3 and later, it is possible to select the memory location for
$AC_PARAM[n] between DRAM and SRAM using the machine data:
MD28255 $MC_MM_BUFFERED_AC_PARAM ($AC_PARAM[] is saved in SRAM)
0: dynamic memory DRAM, (default)
1: static memory SRAM
2000 can be specified as the highest value in the machine data MD28255.
One element requires 8 bytes. You must ensure that sufficient memory of the correct type is
available.
Synchronization parameters saved in SRAM can be included in the data backup. See
Chapter "System variables saved in SRAM (SW 6.3 and later)"
Synchronized actions
Function Manual, 11/2006, 6FC5397-5BP10-2BA0
2.3 Special real-time variables for synchronized actions
Detailed description
31