8086汇编输出指定阶数的乘法口诀表（带提示信息，范围：1~181，其中1~9阶表左对齐输出）

Posted 2021-12-07 u25th_engineer

图 1 程序运行示意（9阶乘法口诀表）

图 2 程序运行示意（8阶乘法口诀表）

图 3 程序运行示意（7阶乘法口诀表）

图 4 程序运行示意（5阶乘法口诀表）

图 5 程序运行示意（1阶乘法口诀表）

图 6 程序运行示意（10阶乘法口诀表）

  可以看到，1~9阶的乘法口诀表是左对齐输出的（博主在代码中做了限制），超出10阶就无法对齐再输出。

stack   segment stack
        db 512 dup(?)
stack   ends
    
data    segment
		msg		db "Enter the rank of the multiplication table you want to be shown:", 0ah, 0dh, '$'
        string1 db "Press any key to continue!", 0ah, 0dh, '$'
		string2 db "*", '$'
		string3 db "=", '$'
		string4 db " ", '$'
data    ends
		
code 	segment
        assume ds: data, cs: code, ss: stack
main:
		mov ax, stack
        mov ss, ax
		mov ax, data
        mov ds, ax
		
		lea dx, msg
		mov ah, 09h
		int 21h
		call	far ptr readsiw
		push	ax
		call	far ptr display_table

		jmp done
		
;
;		Input: 		ax register, the rank of the multiplication table to be shown
;		Output:		None
;		Function:	To display the multiplication table with specific rank assigned by user
;
display_table	proc	far
		push	bp
		mov	bp,sp
		push	si
		push	di
	
		mov	si,1
		jmp	short out_loop
in_loop:	
		mov	di,1
		jmp	short new_line
display_equation:	
		mov	ax,di
		push ax
		call	far ptr dispsiw
		
		lea dx, string2		; *
		mov ah, 09h
		int 21h
		
		pop ax
		
		push ax
		mov ax, si
		call	far ptr dispsiw
		pop ax
		
		imul	si
		push ax
		lea dx, string3		; =
		mov ah, 09h
		int 21h
		
		pop ax
		call	far ptr dispsiw
		cmp ax, 10
		jl two_spaces
		
		push ax
		
		lea dx, string4
		mov ah, 09h
		int 21h
		
		pop ax
		
		jmp continue_in_loop
		
two_spaces:
		push ax
		
		lea dx, string4
		mov ah, 09h
		int 21h

		lea dx, string4
		mov ah, 09h
		int 21h
		
		pop ax
		
		jmp continue_in_loop
continue_in_loop:
		inc	di
new_line:
		cmp	di,si
		jle	short display_equation
		
		call	far ptr lineFeed
		inc	si
out_loop:
		cmp	si,word ptr [bp+6]
		jle	short in_loop
	
		pop	di
		pop	si
		mov	sp,bp
		pop	bp
		ret	
display_table	endp

readsiw proc	far
		push bx
		push cx
		push dx
		xor bx, bx   
		xor cx, cx   
		mov ah, 1
		int 21h
		cmp al, '+'
		jz rsiw1
		cmp al, '-'
		jnz rsiw2
		mov cx, -1
rsiw1: 
		mov ah,  1
		int 21h
rsiw2:    
		cmp al, '0'
		jb rsiw3
		cmp al, '9'
		ja rsiw3
		sub al, 30h
		xor ah, ah
		shl bx, 1
		mov dx, bx
		shl bx, 1
		shl bx, 1
		add bx, dx
		add bx, ax
		jmp rsiw1
rsiw3:
		cmp cx, 0
		jz rsiw4
		neg bx
rsiw4:
		mov ax, bx
		pop dx
		pop cx
		pop bx
		ret
readsiw endp

dispsiw proc	far
		push ax
		push bx
		push dx
		test ax, ax 
		jnz dsiw1
		mov dl, '0' 
		mov ah, 2
		int 21h
		jmp dsiw5
dsiw1:
		jns dsiw2  
		mov bx, ax
		mov dl, '-'
		mov ah, 2
		int 21h
		mov ax, bx
		neg ax 
dsiw2:  
		mov bx, 10
		push bx 
dsiw3:
		cmp ax, 0
		jz dsiw4
		xor dx, dx 
		div bx  
		add dl, 30h  
		push dx     
		jmp dsiw3
dsiw4:
		pop dx
		cmp dl, 10
		je dsiw5
		mov ah, 2
		int 21h
		jmp dsiw4
dsiw5:
		pop dx
		pop bx
		pop ax
		ret
dispsiw endp

lineFeed proc	far
		push ax
		push dx
		mov dl, 0dh
		mov ah, 2
		int 21h
		mov dl, 0ah
		mov ah, 2
		int 21h
		pop dx
		pop ax
		ret
lineFeed endp

done:		
		lea dx, string1
		mov ah, 09h
		int 21h
		
		mov ah, 07h
		int 21h
		
		
		mov ah, 4ch
		int 21h
code	ends
		end main