Siemens SINUMERIK 840D sl Function Manual page 921

If continuous path control (G64) is programmed, a non-modal stop is generated internally in
the control.
Examples:
COUPDEF (S2, S1, 1.0, 1.0, "FINE, "DV")
:
COUPON (S2, S1, 150)
:
COUPOF (S2, S1, 0)
:
COUPDEL (S2, S1)
1. COUPOFS(FS, LS)
2. COUPOFS(FS, LS, POS
14.2.3 Axial system variables for synchronous spindle
Determining current coupling status
The current coupling status of the following spindle can be read in the NC part program with
the following axial system variable:
$AA_COUP_ACT[<axial expression>]
For explanation of <axial expression> refer to "Synchronous mode (Page 899) ".
Example:
$AA_COUP_ACT[S2]
The value read has the following significance for the following spindle:
Byte = 0:
Bit 2 = 1:
Bit 2 = 0:
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Deactivating a coupling with stop of following spindle. Block change performed as quickly
as possible with immediate block change)
After the programmed deactivation position that refers to the machine coordinate system
has been crossed, the block change is not enabled until the deactivation positions
POSFS have been crossed.
Value range 0 ... 359.999°.
No coupling active
Synchronous spindle coupling active
Synchronized spindle coupling is not active
Programming of synchronous spindle couplings
)
FS
Synchronous Spindles (S3)
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