Siemens SINUMERIK 840Di sl Function Manual page 95

MEAC
... DO MEAC[axis]=(mode, No_FIFO, trigger events)
The variables $AC_FIFO (see Chapter "FIFO-variables (circulating memory)".) are provided
for the purpose of storing measured values from cyclic measuring processes. Mode and
trigger event see above
Examples:
Two FIFOs have been set up in machine data for the following examples.
Machine data:
MD28050 $MC_MM_NUM_R_PARAM = 300
MD28258 $MC_MM_NUM_AC_TIMER = 1
MD28260 $MC_NUM_AC_FIFO = 2
MD28262 $MC_START_AC_FIFO = 100
MD28264 $MC_LEN_AC_FIFO = 22
MD28266 $MC_MODE_AC_FIFO = 0
Example 1:
All rising edges of probe 1 must be recorded on a path between X0 and X100. It is assumed
that no more than 22 edges will occur.
Program 1:
DEF INT NUMBER
DEF INT INDEX_R
N0
N1
OC2
N3
N4
N5
N6
N7
N8
Example 2:
All rising and falling edges of probe 1 must be recorded on a path between X0 and X100.
The number of trigger events that may occur is unknown. This means: The measured values
must be fetched and stored in ascending and descending order in R1 as a parallel operation
in a synchronized action. The number of stored measured values is entered in R0.
Synchronized actions
Function Manual, 11/2006, 6FC5397-5BP10-2BA0
G0 X0
MEAC[X]=( 1, 1, 1) POS[X]=100
STOPRE
MEAC[X]=(0)
NUMBER = $AC_FIFO1[4]
NUMBER = NUMBER - 1
FOR INDEX_R= 0 TO NUMBER
R[INDEX_R]= $AC_FIFO1[0]
ENDFOR
2.4 Actions in synchronized actions
; 2 FIFOs
; first FIFO starts from R100
; each FIFO can take up 22 values
; No summation
; Mode = 1, simultaneous
; No-FIFO = 1
Trigger event 1 = rising edge,
;
Probe 1
;
; Stop preprocessing
; Abort continuous measurement
; Number of measured values received in
; of the FIFO variables
; Enter FIFO content in R0 - ...
; After reading the FIFO variable is empty
Detailed description
95