Yealink SIP-T4X Administration Manual page 72

The following table lists the soft keys available for IP phones in different states:
Call State
CallFailed
CallIn
Connecting
Connecting
SemiAttendTrans
Dialing
RingBack
RingBack
SemiAttendTransBack
Talking Talk
Configuring Basic Features
Default Soft Key
NewCall
Empty
Empty
Empty
Answer
Forward
Silence
Reject
Empty
Empty
Empty
Cancel
Transfer
Empty
Empty
Cancel
Send
IME
Delete
Cancel
Empty
Empty
Empty
Cancel
Transfer
Empty
Empty
Cancel
Transfer
HOLD
Optional Soft Key
Empty
Switch
Cancel
Empty
Switch
Empty
Switch
Empty
Switch
Empty
History
Switch
Line
Favorite
GPickup
DPickup
Empty
Switch
CC
Empty
Switch
CC
Empty
MUTE
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