This is the code.............

dosseg
.model small
.stack 200h
.data
.code

start:
mov ax, 0a000h
mov es, ax

mov ax, 100
mov bx, 100
mov cx, 200

sub cx, ax
mov di, ax
mov dx, bx
shl bx, 8h
shl dx, 6h
add dx, bx
add di, dx

mov al, 1
rep stosb
end start

The assembler is masm32, the file name is simple.asm, and here is my problem............

Assembling: simple.asm
simple.asm(19) : error A2070: invalid instruction operands
simple.asm(20) : error A2070: invalid instruction operands


Please help, it's easy right? Thanks.