Activate Default Memory - Siemens SINUMERIK 840Di Function Manual

Dynamic response
Involutes that begin or end on the base circle have an infinite curvature at this point. The
"Velocity limiting profiles" function must be activated in order for the velocity at this point to
be sufficiently limited during active tool radius correction:
MD28530 $MC_MM_PATH_VELO_SEGMENTS > 1
A setting of 5 is recommended. This setting need not be made if only involute sections are
used, which have radii of curvature that change over a relatively small area.
2.2.3

Activate DEFAULT memory

GUD start values
The DEF... / REDEF... NC commands can be used to assign default settings to global user
data (GUD). These default settings must be permanently stored in the system if they are to
be available after certain system states (e.g., RESET).
The memory area for this is taken from the memory area assigned with machine datum:
MD18150 $MM_GUD_VALUES_MEM.
The setting for activation of the saved default values is made with machine datum:
MD11270 $MN_DEFAULT_VALUES_MEM_MASK.
References:
/FB/Description of Functions, Basic Machine/S7: "Memory Configuration"
/PGA/Programming Guide Advanced
2.2.4 Read/write PLC variable
High-speed data channel
For high-speed exchange of information between the PLC and NC, a memory area is
reserved in the communications buffer on these modules (dualport RAM). Variables of any
type (I/O, DB, DW, flags) may be exchanged within this memory area.
The PLC accesses this memory using 'Function Calls' (FC) while the NCK uses '$ variables'.
Various NC/PLC Interface Signals and Functions (A2)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed Description
2.2 Functions
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