Global Constants

[Cisano]

My game has 4k+4k and I need global static variables.

If it possible to define them in one bank only?

If yes, how? Thanks.

 

Edited February 14, 2022 by Cisano

[+Karl G]

Unless I am misunderstanding you here, all 128 bytes of your zero page RAM will be accessible from both banks. 

 

Edit: I misread your question. I don't know of a way to force variables to only be visible from one bank. 

 

 

[Cisano]

I have this (a small part) in my code in the Bank 0

FreqFtgrGrp0
	.byte #5
ColorWall
	.byte #$f4
ColorWater
	.byte #$94

Now, in the Bank 1 I have some code uses these variables.

I don't want to re-define in the Bank 1, because I must change the name.

How can I use them in the Bank 1?

[+splendidnut]

Are they variables (will be changed while the game is running) or are they constants (set once, never changed again)?

[Cisano]

They are constants.

Oh, I made a mistake in the title... (now changed)

 

[+splendidnut]

FreqFtgrGrp0 = 5
ColorWall = $f4
ColorWater = $94

;-- an example of usage:

	LDA  #ColorWall
	STA  COLUPF

You just need to treat constants as labels that get assigned values. 

[+Andrew Davie]

Have a master file that includes all the other files.

e.g., "main.asm" includes "zeropage.asm" and "BANK1.asm" etc.

when you assemble, you assemble "main.asm".

The vars and constants get defined, wherever, somewhere in that (or included files)... and when your banks come around, those symbols are already defined. In fact dasm doesn't need stuff to be defined before use; the assembler does multiple passes. 

Does this help?

 

 

edit: I guess I misunderstood the Q! 

Edited February 14, 2022 by Andrew Davie

[Thomas Jentzsch]

1 hour ago, Cisano said:

 

FreqFtgrGrp0
	.byte #5
ColorWall
	.byte #$f4
ColorWater
	.byte #$94

 

You are not defining variables or constants here. You are defining data which is stored in ROM.

 

For constants see @splendidnut's post.

[Cisano]

Everywhere the variable is used, get the that value.

But only in the Bank where is declared.

 

A solution for both the Banks?

 

PS. Andrew Davie all the code is amost done and this is the last step.

[glurk]

3 hours ago, Cisano said:

I have this (a small part) in my code in the Bank 0

FreqFtgrGrp0
	.byte #5
ColorWall
	.byte #$f4
ColorWater
	.byte #$94

Now, in the Bank 1 I have some code uses these variables.

I don't want to re-define in the Bank 1, because I must change the name.

How can I use them in the Bank 1?

Those are not variables or constants.  Those are tables.  Three one-byte tables.  As was said, just define them as labels.

[Cisano]

Ok, Ok I have understood my mistake and how to do.

That was a table

 

Thanks to all.

When complete, I show you the game.

Bye.

[tokumaru]

There are legitimate reasons for having equivalent tables in multiple banks with different contents though, even though it turned out that this was not what the OP needed.

 

If that was the case though, you'd just need to make sure that the tables started at the same addresses in every bank, and that all the lengths matched. Only one set of tables would need labels. For the others, you could optionally write code to have the assembler validate their positions (i.e. compare the PC at the position where the label would be to the label of the original table and stop assembly in case of a mismatch).

[+SpiceWare]

To build upon @splendidnut's example, if you define color constants you can easily switch between NTSC and PAL builds:

 

NTSC    = 0
PAL     = 1
PAL60   = 2
COMPILE_VERSION = NTSC


BLACK           = $00
WHITE           = $0E
 IF COMPILE_VERSION = NTSC
GREY            = $00
YELLOW          = $10
ORANGE          = $20
RED_ORANGE      = $30
RED             = $40
PURPLE          = $50
VIOLET          = $60
INDIGO          = $70
BLUE            = $80
BLUE2           = $90
TURQUOISE       = $A0
CYAN            = $B0
GREEN           = $C0
YELLOW_GREEN    = $D0
OCHRE_GREEN     = $E0
OCHRE           = $F0
 ELSE
GREY            = $00
YELLOW          = $20   ; no real equivalent
ORANGE          = $20
RED_ORANGE      = $40
RED             = $60
PURPLE          = $80
VIOLET          = $A0
INDIGO          = $C0
BLUE            = $D0
BLUE2           = $B0
TURQUOISE       = $90
CYAN            = $70
GREEN           = $50
YELLOW_GREEN    = $30
OCHRE_GREEN     = $30   ; no real equivalent
OCHRE           = $20   ; no real equivalent
 ENDIF

 

Then use those constants in your code like this:

  lda #GREEN+4
  sta COLUP0
  lda #VIOLET+8
  sta COLUP1

 

The +4 and +8 set the LUMA value.

[+Al_Nafuur]

27 minutes ago, SpiceWare said:

 

Then use those constants in your code like this:

  lda #GREEN+4
  sta COLUP0
  lda #VIOLET+8
  sta COLUP1

 

The +4 and +8 set the LUMA value.

 

You might also use constants for the LUMA :

 

DARKEST      = $0
DARKER       = $2
DARK         = $4
LIGHT        = $6
LIGHTER      = $8
BRIGHT       = $A
BRIGHTER     = $C
BRIGHTEST    = $E


	lda #DARKEST+GREEN

 

[Cisano]

Thanks to everyone.