Siemens SINUMERIK 840D sl Turning Operating Manual page 177

Note
Block-by-block execution
The <SINGLE BLOCK> key is also active in the overstore mode. If several blocks are entered
in the overstore buffer, then these are executed block-by-block after each NC start
Deleting blocks
Turning
Operating Manual, 06/2019, A5E44903486B AB
Press the "Delete blocks" softkey to delete program blocks you have
entered.
Machining the workpiece
6.9 Overstore
177