Macro Issue

[Mikes360]

Hi Guys,

 

I have created a little macro to pad my graphics with zero bytes and I would like to use it in the following way.

 

Here is the macro:

	MAC ZERO_PAD 
.COUNT SET {1}
	ECHO "### ZERO_PAD ", [.COUNT]d
	REPEAT .COUNT 
		.byte #0
	REPEND
	ENDM

And here is a example of how I would like to use it:

    ZERO_PAD PLAYER_HEIGHT - 5

PlayerStopped
    .byte #%00000000
    .byte #%00000000
    .byte #%00100100
    .byte #%01111110
    .byte #%00101100
    .byte #%00101000
    .byte #%00101000 ;--
    .byte #%00111000
    .byte #%00110000
    .byte #%10110010
    .byte #%01111100
    .byte #%00110000 ;--
    .byte #%00111000
    .byte #%01111000
    .byte #%00111000
    .byte #%00111000
PLAYER_HEIGHT = (* - PlayerStopped)
	echo "PLAYER_HEIGHT = ", [PLAYER_HEIGHT]d

I know the issue is with the fact I am using PLAYER_HEIGHT before it is defined but I though the assembler might be cleaver enough to work this out via multiple passes.

 

Is this something that should work? I know if I use the ZERO_PAD macro after PLAYER_HEIGHT is defined it then works.

 

Thanks,

Mike

 

[Thomas Jentzsch]

Unfortunately DASM is not smart enough here. I suppose to add a check inside the macro and skip if PLAYER_HEIGHT is still uninitialized (= 0).

 

BTW: Instead of the loop you can simply use: ds {1}, 0

[Mikes360]

Thanks if I add a check in to the macro it won't try again the second time around so it never actually inserts the zeros I have decided to do this a bit more manually with a bit of validation to make sure I don't mess up the tables down the line

;============================================================================== 
;                               R A I L - D A T A
;============================================================================== 

RAIL_START = 80
RAIL_HEIGHT = 23

RailTable2 SUBROUTINE
    ZERO_PAD PLAYFIELD_START - RAIL_START - RAIL_HEIGHT  
.start
    .byte #%00000000
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010

    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010

    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010

    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010

    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    ;----- 
    IF (* - .start) != RAIL_HEIGHT
        ECHO "Rail table not the same as its defined height", [(* - .start)]d
        ERR
    ENDIF
    ;-----
    ZERO_PAD RAIL_START

Edited January 4, 2015 by Mikes360

[Thomas Jentzsch]

Weird, because for me it works that way.

[Mikes360]

would you mind posting your version of the macro? Mine is:

	MAC ZERO_PAD 
	IF {1} > 0
	ECHO "### ZERO_PAD ", [{1}]d
		ds {1}, 0
	ENDIF
	ENDM

[Thomas Jentzsch]

Nothing special:

    MAC ZERO_PAD
.COUNT SET {1}
  IF .COUNT > 0
    ECHO "### ZERO_PAD ", [.COUNT]d
     ds .COUNT, 0
  ENDIF
    ENDM

And your macro works for me too. Edited January 4, 2015 by Thomas Jentzsch

[Mikes360]

Actually I just tired it again and its not what I thought its failing to assemble the code altogether

 

When I try the following

Test 
    ZERO_PAD TEST_HEIGHT - 1
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
    .byte #%00000010
TEST_HEIGHT = (* - Test)  

I get this in my output

    116  c20a				   Test
      0  c20a					      ZERO_PAD	TEST_HEIGHT - 1
      1  c20a					      IF	TEST_HEIGHT - 1 > 0
 ### ZERO_PAD  4
      2  c20a					      ECHO	"### ZERO_PAD ", [TEST_HEIGHT - 1]d
      3  c20a		       00 00 00 00	      ds	TEST_HEIGHT - 1, 0
      4  c20e					      ENDIF
    118  c20e		       02		      .byte.b	#%00000010
    119  c20f		       02		      .byte.b	#%00000010
    120  c210		       02		      .byte.b	#%00000010
    121  c211		       02		      .byte.b	#%00000010
    122  c212		       02		      .byte.b	#%00000010
Graphics.asm (123): error: EQU: Value mismatch.
    123  c212		       00 09	   TEST_HEIGHT =	(* - Test)

[Thomas Jentzsch]

Ah, that's the problem. You are assigning different values to TEST_HEIGHT. You can try using SET instead of =, but I am not sure if it will work.

 

Your previous approach works.

Edited January 4, 2015 by Thomas Jentzsch

[Mikes360]

Ok I understand now thanks for your help... Again, one day ill be able to spot this myself.