Screen Processing

Screen Processing

The monitor

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08/21/09

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A typical video screen has 80 columns numbered 0 to 79 and 25 rows numbered from 0 to 24 The columns and rows provide a grid of addressable locations at any one of which the cursor can be set Example cursor locations:

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Clearing the screen in assembly language 08/21/09

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Interrupt 10h function 06h handles the process of clearing the screen and scrolling MOV AH, 06H MOV BH, 07H MOV CX, 0000H MOV DX, 184FH INT 10H

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Setting the cursor position 08/21/09

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Interrupt 10h is the BIOS operation for screen handling and function 02h tells the operation to set the cursor MOV AH, 02H MOV BH, 00H MOV DH, 0AH MOV DL, 08H INT 10H

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Displaying the character ‘x’ at the center of the screen 08/21/09

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Displaying a string at the center of the screen 08/21/09

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Displaying ASCII character set 08/21/09

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Color chart 08/21/09

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For colored monitors, the background can display one out of eight colors and text can display one out of 16 colors

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08/21/09

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Text and background color 

Example how to set the text and background colors and how to make them blink

Displaying character ‘x’ with attribute 08/21/09

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Displaying a string with attributes 08/21/09

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