x86 Assembly help, one last time!

clsCorwin

Tried to tack this onto an old thread, but she got no love.

I'm running into some issues with a macro in my program.

lab8.asm

INCLUDE input
INCLUDE input2

.MODEL  SMALL

.STACK  100h

.DATA
	basePrompt	db	'Please enter a number for the base: $'
	expPrompt	db	'Please enter a number to raise the base to: $'
	base		db	?
	exp		db	?
	binBase		db	?
	binExp		db	?
	baseSize	db	?
	expSize		db	?
	answerSize	db	?
	answer		dw	1
	divider		db	10
	ASCIIanswer	dw	?
	cheat		db	'$'

.CODE
	EXTRN GETNUMBER:far, PUTNUMBER:far, POWER:far

MAIN PROC
	mov	ax, @data
	mov	ds, ax
	
	lea	dx, basePrompt
	mov	ah, 09h
	int	21h			;display prompt	
	INPUT	base			;get base number
	
	lea	dx, expPrompt
	mov	ah, 09h
	int	21h			;display prompt
	INPUT2	exp			;get exponent
	
	call	GETNUMBER		;convert numbers to binary
	
	mov	ax, 0
	mov	al, binBase
	call	GETSIZE			;get number of digits in base
	;mov	baseSize, bl		;set base size
		
	mov	ax, 0
	mov	al, binExp
	call	GETSIZE			;get number of digits in exp
	;mov	expSize, bx		;set exp size	
	
	call	POWER			;raise base to exp power
	
	mov	ax, answer
	call	GETSIZE			;get number of digits in answer
	mov	bx, 0
	mov	answerSize, bl		;set answer size
	
	call	PUTNUMBER		;convert answer to ascii for printing
	call	PRINT			;print answer
	
	mov	ax, 4c00h
	int	21h			;terminate program
	
MAIN ENDP

GETSIZE PROC
	cmp	ax, 10000		;compare num to 10000
	jb	NOT5			;if smaller, jump to NOT5
	mov	bx, 5			;else size = 5

	NOT5:
	cmp	ax, 1000		;compare num to 1000
	jb	NOT4			;if smaller, jump to NOT4
	mov	bx, 4			;else size = 4

	NOT4:
	cmp	ax, 100			;compare num to 100
	jb	NOT3			;if smaller, jump to NOT3
	mov	bx, 3			;else size = 3

	NOT3:
	cmp	ax, 10			;compare num to 10
	jb	CONTINUE1		;if smaller, size = 1
	mov	bx, 2			;else size = 2
	
	CONTINUE1:
	mov	bx, 1			;size = 1
	
	ret
GETSIZE ENDP

PRINT PROC
	mov	ax, ASCIIanswer
	mov	ah, 09h
	int	21h			;print answer

PRINT ENDP

END MAIN

input

INPUT MACRO addr
	lea	bx, addr		;load addr into bx
	mov	cx, 2			;set counter to 2
	mov	si, 0			;set pointer to 0
	
INLOOP:
	mov	ah, 01h
	int	21h			;get char from keyboard
	mov	bx + si, al		;put char into bx
	inc	si
	loop	INLOOP
	
ENDM

This is the output I get upon trying to assemble lab8.asm:

Turbo Assembler Version 4.1 Copyright (c) 1988, 1996 Borland International

Assembling file: lab8.asm
**Error** lab8.asm(61) INPUT(8) Too many registers in expression
**Error** lab8.asm(66) INPUT2(8) Too many registers in expression
Error messages: 2
Warning messages: None
Passes: 1
Remaining memory: 413k


Tool completed with exit code 1

Mind you, this is 16 bit assembly for x86. Why is it complaining about the macro?

Bama

I looks like you're trying to put the sum of two registers in another register with a mov instruction. Shouldn't you be using an add? I can't think of an instance where an expression is a valid instruction parameter.

Smasher

I have no experience with x86 assembly, but I'll give this a stab. Take with a grain of salt.

It looks like it's complaining about one of these two lines, depending how it counts line numbers in macros:

int 21h
mov bx + si, al

The int seems to look fine, so my hunch is that you're not allowed to add bx and si together like that. I don't know if that's actually true, but I notice you don't do it anywhere else in the code there. Try summing them in an extra register first (if you have a free one) and using that in the mov statement instead.

clsCorwin

Yep, I'm a jackass.

Fristle

mov        bx + si, al                ;put char into bx

Yea that looks invalid.

If you need to put AL into the address [BX plus an offset of SI] then you will have to store that address in another register first, then do a mov of AL to that address.

Edit: beat to the punch!

ecco the dolphin

mov [bx + si], al

Is what you want.

Ha, sorry about the other thread - absolutely forgot about it last night.

EDIT: Woah, lots of answers all of a sudden. Anyway, no need to have another register - you can directly add si to bx in this context.