Atari 1200 XL, Руководство по обслуживанию на месте

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Memory
Audio Visual
Keyboard
All Tests
Press the SELECT key to move the selection down a line until you reach the desired test. Press
the START key to begin the test.
CAUTION: Self Test will not go into Attract Mode. Do not leave the TV set on any of the Self
Test screens for any length of time, since screen burning can occur.
MEMORY TEST SCREEN
Purpose: To test ROM, RAM and ANTIC chips.
Format: Two long bars display at the top of the screen. Below them are three rows with sixteen
blocks representing the RAM (each block represents 1 K). The two long bars displayed at the
top of the screen represent the two 8K ROMs in the
system. When either ROM or RAM is being tested,
the corresponding bar segment color is white. If the
ROM or RAM tests good, the bar color changes to
light green. If the ROM or RAM tests defective, the
color changes to red. Once a ROM or RAM has been
tested and found defective the bar remains red and is
not tested again on subsequent test passes.
During the RAM test the LEDs cycle one on and one
off. On exiting the Memory tests the LEDs will be left in the off state.
The Memory Test loops and continues testing until either the HELP or RESET key is pressed.
AUDIO VISUAL TEST SCREEN
Purpose: To test the ANTIC and POKEY chips.
Format: This screen displays a music staff and treble
clef. A sequence of six notes plays and the
corresponding note shows on the staff. The tune plays
sequentially from channel one through channel four.
The channel number changes for each according to
the sound channel in use. Voice #1-4 under the staff
and treble clef indicates the channel in use. There is a
slight pause between each voice.
1200XL Home Computer
Field Service Manual
3-2