data segment data ends tack segment stack dw 100 dup (? tos label word stack ends e segment start. push ds sub ax, ax push ax PSP mov ax. data moV ds ax ret code ends en d start8 PSP DS→ ES SS→ CS→ data segment …… data ends stack segment stack dw 100 dup (?) tos label word stack ends code segment …… start: push ds sub ax, ax push ax mov ax, data mov ds, ax …… ret …… code ends end start