CODEWITHSUNDEEP
parametersreturnproceduremasm
user3041058
user3041058

Reputation: 1548

Procedures with parameters in MASM?

How can a write a procedure in MASM that accepts one or more parameters and return one or more values ?

I am trying the following code,

DATA SEGMENT

DATA ENDS
;;===================================
MYPROCS SEGMENT

CONV_ROUT   PROC VAL:BYTE

RET VAL
CONV_ROUT ENDP

MYPROCS ENDS
;;===================================
CODE SEGMENT
ASSUME CS:CODE,DS:DATA
START:  MOV AX,DATA
MOV DS,AX

CALL FAR PTR CONV_ROUT AL

MOV AH,4CH
INT 21H

CODE ENDS
END START

Currently, the above code gives the following error

q3.asm(7): error A2119: language type must be specified
q3.asm(9): error A2006: undefined symbol : VAL
q3.asm(19): error A2206: missing operator in expression

Upvotes: 0

Views: 2921

Answers (1)

rkhb
rkhb

Reputation: 14409

You must decide which "calling convention" you take. The following example uses "stdcall". The arguments are passed on the stack and the return value is in AX. The stack will be cleared by the procedure ("callee").

.MODEL SMALL, STDCALL

DATA SEGMENT

DATA ENDS
;;===================================
MYPROCS SEGMENT
ASSUME CS:MYPROCS

CONV_ROUT   PROC FAR VAL:WORD
MOV AX, VAL
RET
CONV_ROUT ENDP

MYPROCS ENDS
;;===================================
CODE SEGMENT
ASSUME CS:CODE,DS:DATA
START:  MOV AX,DATA
MOV DS,AX

PUSH AX
CALL FAR PTR CONV_ROUT

MOV AX,4C00H
INT 21H

CODE ENDS
END START

I would advise you not to use far calls and far procedures, if you don't really need it.

Upvotes: 1

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