HEIDENHAIN MANUALPLUS 620 User Manual page 148

V Feed rate reduction
0: No reduction
1: At the end of the hole
2: At the beginning of the hole
3: At the beginning and end of the hole
AB Spot drilling / through drilling length (distance for feed rate
reduction)
RB Return plane (default: return to the starting position or to
the safety clearance)
Further forms: see page 46
148 smart.Turn Units for the Y Axis