Problem :
What makes the FAR CALL to external procedure is set always to jump to CS:IP=0000:0000 ? which when traced by the debugger "CodeView" doesn't contain the actual procedure.
I make four public procedures in four different files , the first three calls work properly but the fourth call is assembled to be : CALL 0000:0000 .
Commenting the first three calls result in the same effect.
Code :
Inside Pro.asm [Which contains the main procedure ]
The first few lines contains the extrn declarations
EXTRN WelScr:FAR
EXTRN RdImgs:FAR
EXTRN DispImgs:FAR
EXTRN MouseAct:FAR
Then inside the main I perform the following calls :
Main_prog PROC FAR
CALL WelScr
CALL RETURN ; another procedure declared inside Pro.asm
CALL ClrScr
CALL RdImgs
;getch() for debug purpose
MOV AH,00
INT 16H
CALL DispImgs
CALL MouseAct ;**Here is the problem**
;Return to DOS
MOV AH,4CH
INT 21H
Main_prog endp
Inside Mouseact.asm first I declared the procedure name to be PUBLIC then two macros are declared after that the external procedure declaration is done
PUBLIC MouseAct
DISPIM1 MACRO SR,SC,dArr
MOV SI,SC;Start Column Pixel
MOV DX,SR;Start Rwo Pixel
LEA DI,dArr+2 ;image data strats from here
CALL DispFile1
DISPIM1 ENDM
ChkClk MACRO i
LOCAL E
CMP DX,75*i
JB RT
CMP DX,75*i+70
JA E
INC ClickNum
CMP ClickNum,2
JE RT ; A lable inside the Mouseact Procedure
MOV ItemNum,i
JMP LOP
E:
ChkClk ENDM
The procedure itself :
Code_segment_name segment
MouseAct PROC FAR
.
.
;the procedure contents are here
.
.
RETF
MouseAct ENDP
Another procedure needed by the MouseAct procedure :
DispFile1 PROC
.
.
;the procedure contents are here
.
.
RET
DispFile1 ENDP
Code_segment_name ends
end
Attached also the MouseAct.lst [The listing file] which is different from other external procedures listings and also doesn't contain the DispFile1 procedure name.
Microsoft (R) Macro Assembler Version 5.10 12/20/15 05:18:0
Symbols-1
Macros:
N a m e Lines
CHKCLK . . . . . . . . . . . . . 0
DISPIM1 . . . . . . . . . . . . 12
Symbols:
N a m e Type Value Attr
MOUSEACT . . . . . . . . . . . . F PROC 0000 Global Length = 0000
@CPU . . . . . . . . . . . . . . TEXT 0101h
@FILENAME . . . . . . . . . . . TEXT mouseact
@VERSION . . . . . . . . . . . . TEXT 510
0 Source Lines
0 Total Lines
13 Symbols
47570 + 451498 Bytes symbol space free
0 Warning Errors
0 Severe Errors
After Some digging ; I discovered that ending the macro dfinition part by macro_name endm i.e. in the above example : DISPIM1 ENDM for DISP1M1 macro and ChkClk ENDM for ChkClk macro makes the assembler stop assembling the rest of the file which leads to the procedure global length=0 making the macro end is ENDM only everything now is OK.