Toshiba Tecra A2-S239 Maintenance Manual - Page 128

3 Tests and Diagnostics 3.8 Display Test 3.8 Display Test To execute the Display Test, select 4 from the DIAGNOSTIC TEST MENU, press Enter and follow the directions on the screen. The Display test contains subtests that test the display in various modes. Move the highlight bar to the subtest you want to execute and press Enter. Subtest 01 VRAM Read/Write for VGA This subtest writes the constant data (AAh and 55h) and the address data to the video RAM. The data is read and compared to the original data. Subtest 02 Gradation for VGA This subtest displays four colors: red, green, blue and white from left to right across the screen from black to maximum brightness. The display below appears on the screen when this subtest is executed. Subtest 03 To exit this subtest and return to the DISPLAY TEST menu, press Enter. Gradation for LCD This subtest displays bands of gradations for mixed colors, then for red, green, and blue. Next, it displays eight solid colors full screen: red, semi-red, green, semi-green, blue, semi-blue, white, and semi-white. The display of each color switches automatically every three seconds. 3-20 Satellite A50/TECRA A2 Maintenance Manual (960-478)