Siemens SINUMERIK 840D sl Programming Manual page 651

$P_CHBFRMASK and $P_NCBFRMASK Complete basic frame
The user can select which basic frames are to be included in the calculation of the "Complete"
basic frame via the system variables $P_CHBFRMASK and $P_NCBFRMASK. The variables
can only be programmed in the program and read via the OPI. The value of the variable is
interpreted as a bit mask and specifies which basic frame field element of $P_ACTFRAME is
to be included in the calculation.
$P_CHBFRMASK can be used to specify which channel-specific basic frames and
$P_NCBFRMASK can be used to specify which global basic frames are to be included in the
calculation.
The complete basic frame and the complete frame are recalculated with the programming of
the variables. After a reset and in the basic setting, the values of $P_CHBFRMASK and
$P_NCBFRMASK are as follows:
$P_CHBFRMASK = $MC_CHBFRAME_RESET_MASK
$P_NCBFRMASK = $MC_CHBFRAME_RESET_MASK
Example:
$P_NCBFRMASK = 'H81' ;$P_NCBFRAME[0] : $P_NCBFRAME[7]
$P_CHBFRMASK = 'H11' ;$P_CHBFRAME[0] : $P_CHBFRAME[4]
$P_IFRAME Current settable frame
The predefined frame variable $P_IFRAME can be used to read and write the current settable
frame, which is valid in the channel, in the part program. The written settable frame is
immediately included in the calculation.
In the case of global settable frames, the modified frame acts only in the channel in which the
frame was programmed. If the frame is to be modified for all channels of a control, $P_UIFR[n]
and $P_IFRAME must be written simultaneously. The other channels must then activate the
corresponding frame, e.g. with G54.
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
Work preparation
3.8 Coordinate transformations (frames)
651