Siemens SINUMERIK 840D sl Operating Manual page 285

Proceed as follows
HMI sl Turning
Operating Manual, 01/2008, 6FC5398-7AP10-0BA0
1. Select the "Machine" operating area.
2. Press the "AUTO" or "MDA" key.
...
3. Press the "TEACH IN" key.
4. Press the "Teach prog." softkey.
5. Click the program block to be deleted.
6. Press the ">>" and "Delete block" softkeys.
The program block on which the cursor is positioned is deleted.
...
Teaching in a program
6.6 Deleting a block
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