Texas Instruments 4000M - Manual (Page 36)

Using the Keyboard
Ctrl-Alt-Del Terminates all programs, reloads MS-DOS and executes the
AUTOEXEC file; also called "warm start" or "warm boot"
Ctrl-Alt-
↓↓
Decreases cpu speed from high to low
Ctrl-Alt-
↑↑
Increases cpu speed from low to high
Ctrl-Alt-D decreases the speaker volume
Ctrl-Alt-U increases the speaker volume.
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