Video memory

I want to print the text directly to the video memory. So what I need is es:di where di points to the offset of the video memory where I want to print the character. How's is it organized? Is it some sort of linear address? How would I calculate the address if I know the column and the row number I want to print on?

I do not know if it's exacly what you want but here is one part of a code for video that I found in a old asm project for school that I have made.

Code:

---

PTAMPON PROC
        PUSH    AX
        PUSH    CX
        PUSH    DI
        MOV        SI, 0
        MOV    AX, 0B800h
        MOV    ES, AX
        MOV    AL, BYTE PTR TAMPON[SI]            ; string to show here!!!!       
MOV    AH, 0f3h            ; color here!!!!
        MOV    DI, 1940d          ; x_yposition here!!!!!

Encore:        INC SI
        MOV    WORD PTR[ES]: DI, AX ; copie dans l'‚cran vid‚o
        INC    DI                ; next char
        INC    DI ;Next char
       
        MOV    AL, BYTE PTR TAMPON[SI]
        CMP        AL, '$'                ; end?
        JNE    Encore            ; not = redo


FINTAMPON:

        POP    DI
        POP    CX
        POP    AX
        RET
ENDP

---

look at simple OS's like linux 0.1 and check out the forums at www.mega-tokyo.com/forum/

Thanks...figured out...