AT&T 6300 Programmer's Manual page 313

Examples
KEY
Statement
(Function Keys)
50 KEY ON
Displays the Soft Keys on the bottom line.
60 KEY OFF
Erases Soft Key display.
70 KEY 1, MENU +CHRS(13)
Assigns the string "MENU" CR to Soft Key 1.
Such assignments might be used for rapid
data entry.
80 KEY 2,
Disables Soft Key 2 as a soft key.
The following routine initializes the first 5
Soft Keys:
1 KEY OFF 'Turn aff key display during
init.
10 DATA KEY1,KEY2,KEY3,KEY4,KEY5
20 FOR 1=1 TO 5:READ SOFTKEYSS(I)
30 KEY I,SOFTKEYSS(I)
40 NEXT 1
50 KEY ON 'naw display new saftkeys.
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