Atari 1200 XL, Руководство по обслуживанию на месте

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KEYBOARD (use Self Test instead of SALT 2.05)
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PORT TEST
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SWITCHES
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TONE TEST (Use Self Test instead of SALT 2.05)
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VERIFY ROM (Use Self Test instead of SALT 2.05)
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ADJUST
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TIA
Disregard the other functions:
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BOOT B
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EXAMINE
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LIGHT PEN
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PRODUCTION TEST
RESET is used to take you from a test back to the SALT Header.
The tests applicable to the 1200XL are discussed on the following pages.
COLOR BAR TEST
This test verifies and allows for adjustment to the color circuitry. Enter the command letter C
and press RETURN to activate this test. Figure 3-3 is a black and white representation of what
your television display screen should look like.
Reference gray bar >Same color rabov
Figure 3-3. Color Bar Test Screen
A 15-color rainbow scale is displayed above the reference bar with a single color bar below. The
color, bars directly above and below the reference bar should be the same color (golden rod). If
not, proper adjustment of VR1 makes the color bars above and below the reference bar
identical, thus adjusting the color frequency of the console to the proper setting. See Figure 4-1
for VR1 loćation. Minor glitches on the edges of the color bars are acceptable. Leave this test on
for at least 60 seconds in order to catch any intermittent problems, such as a bar momentarily
changing colors or blanking out. .
1200XL Home Computer
Field Service Manual
3-5