The attachment IMG_7401r.jpg is no longer available
I had an idea for a little improvement 😉
____
a
nop
xor ax,ax
push ax
pop ds
mov ax,[40]
mov bx,[42]
push cs
pop ds
mov [251],ax
mov [253],bx
xor ax,ax
push ax
pop ds
mov ax, cs
mov [42],cs
mov ax,200
mov [40],ax
mov ah,0
mov al,10
int 10
mov ah,31
mov dx,100
int 21
a 200
cmp ah, 0f
je 230
cmp ah,0
jne 250
push ds
push cs
pop ds
mov [231],al
pop ds
out 80,al
mov al,10
jmp 250
a 230
mov al,12
mov ah,0
mov bh,0
jmp 250
a 250
jmp aabb:ccdd
retf
n test.com
rcx
500
w
q
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Now the programs switches to the selectes graphics mode (10 in example above) and stays with it in all case. Therefore you can easily test if the problem is related to windows or if you have a general problem. Will only work with grpahics mode programs and only if they use BIOS call to set up the mode.
Tested with SQ3, Xenon II, Populous and Windows and seem to work. Looks of course messed up, think Scali can explain better than me why 😉 You can even see the graphics if you select a 256 VGA color mode in a game. Should start to write a VGA emulator for a EGA card 😉
So to test 640x480 replace the two bold "10" by a "12" and try...only way to exit is a reset.
