Siemens SINUMERIK 840D sl Function Manual page 855

2.4.5 Frame chain frames
2.4.5.1 Overview
There are up to four frame variants:
• Settable frames (G500,G54 to G599)
• Basic frames
• Programmable frame
• System frames
2.4.5.2 Settable frames $P_UIFR[n]
The number of NCU global settable frames is set through the following machine data:
MD18601 $MN_MM_NUM_GLOBAL_USER_FRAMES (number of global, pre-defined user
frames (SRAM))
The number can be between 0 and 100. If the MD has a value greater than zero, there are
only NCU global settable frames, otherwise the following machine data specifies the number
of channel-specific settable frames:
MD28080 $MC_MM_NUM_USER_FRAMES (number of settable frames (SRAM))
System variable $P_UIFR[n] can be used to read and write the frame field elements. The
frame is not activated simultaneously when writing a field element, but rather activation only
takes place on execution of a G500,G54, to G599 instruction. For NCU global frames, the
changed frame only becomes active in those channels of the NCU, which execute a
G500,G54 to G599 instruction. The variable is used primarily for storing write operations
from HMI or PLC. These frame variables are saved by the data backup.
Current settable frame $P_IFRAME
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 NCU 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 an NCU, $P_UIFR[n] and $P_IFRAME must be written
simultaneously. The other channels must then activate the corresponding frame, e.g., with
G54.
Programming of settable frames
Settable frames can be read and written via the part program and via the OPI by operator
actions and by the PLC. However, only data management frames can be written by the OPI.
The index of the active settable frame can be ascertained via the $P_UIFRNUM system
variable.
Basic logic functions: Axes, coordinate systems, frames (K2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed description
2.4 Frames
71