title Swap color mono display page ,132 ; this routine swaps between the b&w display and the color display ; on the IBM personal computer. 80 character width is always selected data segment at 40h org 10h eqflg dw ? ;equipment flag org 49h curvid db ? ;current state data ends code segment assume cs:code,ds:data swap proc far push ds ;save dos's data segment xor ax,ax ;zero AX for return push ax mov ax,data ;establish addressing mov ds,ax cmp curvid,7 ; if it is 7, the monochrome display jnz color ; is in use, and we swith to color. mono: mov ax,eqflg ;switch to color and al,0cfh or al,20h ;I don't know what these bits do!!! mov eqflg,ax jmp exit color: or eqflg,30h ;switch to mono exit: mov ax,3 int 10H ret swap endp code ends end