qa.hlp (Table of Contents; Topic list)
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WriteTTY
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;* WriteTTY - Displays ASCIIZ string at cursor position, in either text
;* or graphics mode.
;*
;* Shows:   BIOS Interrupt - 10h, Function 0Eh (Write Character in TTY mode)
;*          Instruction - loop
;*
;* Uses:    vconfig - Video configuration structure, declared in the
;*          DEMO.INC include file. The structure must first be
;*          initialized by calling the GetVidConfig procedure.
;*
;* Params:  str - Pointer to ASCIIZ string
;*          icolor - Color index (for graphics mode only)
;*
;* Return:  None
 
WriteTTY PROC \
        USES ds si, \
        str:PTR BYTE, icolor:WORD
 
        mov     bx, icolor              ; BL = color index
        mov     bh, vconfig.dpage       ; BH = current display page
        LoadPtr ds, si, str
        mov     cx, -1                  ; Set loop counter to maximum
        mov     ah, 14                  ; Function 14
loop1:  lodsb                           ; Get character from string
        or      al, al                  ; NULL string terminator?
        jz      exit                    ; Yes?  Exit
        int     10h                     ; No?  Display, advance cursor
        loop    loop1                   ; Loop to get next character
exit:   ret
 
WriteTTY ENDP
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