Toshiba Satellite Pro U400 Series, Maintenance Manual

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Test Program for Field.
Satellite U400 and Satellite Pro U400 Tests and Diagnostics Manual
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3.12 High Resolution Display Test
To execute the High Resolution Display Test select 09 from the Diagnostic Test Menu, press
Enter and follow the directions on the screen. The High Resolution Display Test contains six
subtests that test the computer's high resolution video display. Move the highlight bar to the
subtest you want to execute and press
Enter .
Subtest 01 VRAM W/R/C Test
This subtest writes address and data patterns to Video RAM, then reads the
values from the Video RAM and compares them to the original test patterns.
During the execution of this test 13 different color screens display: black,
green, green, blue, blue, red, red, red, black, white, pink, cyan, and black.
Test Process:
1. Sets the video display to 1024*768 mode
2.
Bank change test
Writes 1 byte data in order 0, 1, through Fh, and compares the result,
at every bank, to the original data patterns.
3.
Bit shift data test
Writes 01h data into addresses A000:0000h through A000:FFFFh for
each bank, reads the new data and, then compares the results with the
original data. Data is then shifted 1 bit to the left, and all bits (01h,
02h, 04h, 08h, through 80h) are tested again.
4. Fixed data test
Writes test data (in order FFh, AAh, 55h, 00h) into addresses
A000:0000h through A000:FFFFh for each bank by, reads the new
data and, then compares the results with the original data. Data is then
shifted 1 bit to the left, and all bits are tested again
NOTE: If NO is selected for Test Loop on the Test Parameter menu, the
screen displays the colors listed above and then the High Resolution
Display Test menu displays.
If YES is selected for Test Loop on the Test Parameter menu, the screen
displays the colors listed above. Press Ctrl + break to return to the High
Resolution Display Test menu.