3 programming the first part, Selecting the correct operating mode, The most important tnc keys – HEIDENHAIN TNC 640 (34059x-05) ISO programming User Manual
Page 51: Programming the first part, Programming the first part 1.3

Programming the first part
1.3
1
TNC 640 | User's ManualDIN/ISO Programming | 1/2015
51
1.3
Programming the first part
Selecting the correct operating mode
You can write programs only in Programming mode:
Press the Programming operating mode key: The
TNC switches to
Programming mode
Further information on this topic
Operating modes: see "Programming", page 74
The most important TNC keys
Key
Functions for conversational guidance
Confirm entry and activate the next dialog
prompt
NO
ENT
Ignore the dialog question
End the dialog immediately
Abort dialog, discard entries
Soft keys on the screen with which you select
functions appropriate to the active operating
state
Further information on this topic
Writing and editing programs: see "Editing a program",
page 106
Overview of keys: see "Controls of the TNC", page 2