Siemens Sinumerik 840D sl Programming Manual page 191

Further information
The different effects of return jump parameters 1 to 3 are explained in the following graphics.
1st return jump parameter 1 = "N200", return jump parameter 2 = 0
After the RET command, program execution is continued with block N200 in the main
program.
2nd return jump parameter 1 = "N200", return jump parameter 2 = 1
After the RET command, program execution is continued with the block (N210) that follows
block N200 in the main program.
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Flexible NC programming
1.25 Subprogram technique
191