在8086上通过TASM将ASCII符号写入视频存储器

Question

I need to write a program for writing ASCII symbols to the video memory.

.model tiny
.stack
.data
.code
main: 

mov ax, 0b800h
mov ds, ax

mov aL, 'x'
mov es, bx
mov es:[1], aL

mov ah, 4ch
int 21h

end main

This code is inert as of yet; it compiles, runs and then exits without printing anything. I think i'm missing a line.

Answer 1

To be able to write to the video memory, set ES to 0b800h Specify the place (Offset), on the screen where you want to write. Set DI to (row*(max. rows (80))+col)*2 (ROW and COL are null-based). For example to write to the third char in the 10th line use "mov di, (2*80+9)*2" Specify the colors in AH. Set AH to (backgroundcolor*16+foregroundcolor) for example to write light gray (7) letters on a black (0) background use "mov ah, 7" Use the STOSW instruction instead of "mov es:[adress]", al. This way you can dynamically write to different places on the screen.