Hitachi CHROMASTER 5160 Instruction Manual page 665

3.3 GLP-Related Functions
3.3.1 Keylock Setting
This function serves to lock the keys on the keyboard, and thus
prevent erroneous activation of keys on the control panel.
GLP (LOGBOOK=1, KEY LOCK=2)
2
KEY LOCK (YES=1, NO=0)
1
LOCK OFF
Clicking the ESC
3 - 15
GLP
2 ENT
1 ENT
Monitor screen
key releases the keylock.
3.3.1