Siemens SINUMERIK 808D - Page 215

Description: $AC_PARAM[] is stored in SRAM.
28256 MM_NUM_AC_MARKER C02 2.3, 6.1
- Dimension of $AC_MARKER DWORD PowerOn
-
- - 8, 8, 8, 8, 8, 8, 8, 8... 0 20000 1/1 M
Description: Number of channel-specific markers $AC_MARKER for motion-synchronous actions.
DRAM or SRAM is required depending on MD28257 $MC_MM_BUFFERED_AC_MARKER.
28257 MM_BUFFERED_AC_MARKER C02 2.3, 6.1
- $AC_MARKER[] is stored in SRAM. DWORD PowerOn
-
- - 0, 0, 0, 0, 0, 0, 0, 0... 0 1 1/1 M
Description: $AC_MARKER[] is stored in SRAM.
28258 MM_NUM_AC_TIMER C02 2.3, 2.4, 6.1
- Number of time variables $AC_TIMER (DRAM) DWORD PowerOn
-
- - 0, 0, 0, 0, 0, 0, 0, 0... 0 10000 1/1 M
Description: Number of channel-specific time variables $AC_TIMER for motion-synchronous actions
(DRAM)
28260 NUM_AC_FIFO C01 2.3, 2.4, 6.1
- Number of FIFO variable for synchronized actions DWORD PowerOn
-
- - 0, 0, 0, 0, 0, 0, 0, 0... 0 10 1/1 M
Description: Number of FIFO variables $AC_FIFO1 - $AC_FIFO10 for motion-synchronous actions.
FIFO variables are used for product tracking. A piece of information (e.g. the product
length) for each part on a conveyor belt can be temporarily stored in each FIFO
variable.
FIFO variables are stored in R variables.
MD28262 $MC_START_AC_FIFO defines the number of the R variable as from which the FIFO
variables
can be
stored. All R variables with lower numbers can be used freely in the
part program.
R variables above the FIFO range cannot be written from the part program.
The number of R variables must set via MD28050 $MC_MM_NUM_R_PARAM so that all FIFI
variables can be accommodated from the start of the R variables:
MD28050 $MC_MM_NUM_R_PARAM = MD28262 $MC_START_AC_FIFO + MD28260 $MC_NUM_AC_FIFO *
(MD28264 $MC_LEN_AC_FIFO + 6)
The FIFO variables bear the names $AC_FIFO1 to $AC_FIFOn.
They are stored as arrays.
The indices 0 - 5 have special meanings:
n= 0:
A new value is stored in the FIFO when writing with index 0.
The oldest element is read and removed from the FIFO when writing with index 0.
n=1: Access to the first element read in
n=2: Access to the last element 1 read in
n=3: Sum of all FIFO elements
n=4: Number of elements available in the FIFO
n=5: Current write index relative to FIFO start
Machine data
3.3 Channel-specific machine data
Parameter Manual
List Manual, 01/2017 215