Sun Microsystems SPARCstation 4, Service Manual

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3-2 SPARCstation 4/Xterminal 1 Service Manual • January 1995
Four different LEDs on the keyboards are used to indicate the progress and results of
the POST. These LEDs are on the Caps Lock, Compose, Scroll Lock, and Num Lock
keys, as shown in
FIGURE 3-1
,
FIGURE 3-2
, and
FIGURE 3-3
. To indicate the beginning of
the POSTs, the four LEDs briefly light all at once. The monitor screen remains blank,
and the Caps Lock LED blinks for the duration of the POST.
FIGURE 3-1
Arrangement of Sun Type-5 Keyboard Diagnostic LEDs
FIGURE 3-2
Sun Type-4 Keyboard
Scroll Lock
LED Num Lock
LED
Caps Lock LED
(UNIX keyboard) Caps Lock LED
(U.S. keyboard) Compose
LED
Caps Lock
LED Compose
LED Scroll Lock
LED Num Lock
LED