Siemens SINUMERIK 840D sl Programming Manual page 535

The following are available as external memory:
● Local drive
● Network drive
● USB drive
Note
Only the USB interfaces on the operator panel front or the TCU can be used as an interface
for processing an external program on a USB drive.
Default setting of the external program path
The path for the external program directory can be preset with the setting data:
SD42700 $SC_EXT_PROG_PATH
Together with the program path and identifier specified with the EXTCALL call, this forms the
entire path for the subprogram to be called.
Note
If the program path is specified only via the EXTCALL call, then SD42700 must be empty.
Note
Parameters
When an external program is called, no parameters can be transferred to it.
Syntax
EXTCALL("<Path/><Program name>")
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NOTICE
Tool/workpiece damage when using a USB flash drive
It is recommended that a USB flash drive is not used to execute an external subprogram.
A communication interruption to the USB flash drive while executing the subprogram as a
result of contact problems, drop out, interruption through a knock or accidental unplugging
stops the machining immediately. The tool and/or workpiece could be damaged.
Work preparation
3.2 Subprogram technique
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