Siemens SINUMERIK 840D sl Function Manual page 601

Note
Subprograms with jump commands
For external subprograms that contain jump commands (GOTOF, GOTOB, CASE, FOR, LOOP,
WHILE, REPEAT, IF, ELSE, ENDIF etc.) the jump destinations must lie within the post loading
memory.
The size of the post loading memory is set via:
MD18360 MM_EXT_PROG_BUFFER_SIZE
ShopMill/ShopTurn programs
The contour descriptions added at the file end mean the ShopMill and ShopTurn programs
must be stored completely in the read-only memory.
Parameterization
The path for the external subprogram directory can be preset using setting data:
SD42700 $SC_EXT_PROG_PATH (program path for the EXTCALL external subprogram
call)
The entire path of the program to be called along with the subprogram path or name specified
during programming is derived therefrom.
Programming
An external subprogram is called by means of parts program command EXTCALL.
Syntax:
Parameter:
<path>:
<program name>:
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
K1: Mode group, channel, program operation, reset response
EXTCALL("<path/><program name>")
Absolute or relative path data (optional)
Type: STRING
The program name is specified without prefix "_N_".
The file extension ("MPF", "SPF") can be attached to program names
using the "_" or "." character (optional).
Type: STRING
9.14 Program control
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