Multibyte constant

From NESdev Wiki
Revision as of 14:36, 2 July 2015 by Hamtaro126 (talk | contribs) (Added macro for ASM6 using HEX)
Jump to navigationJump to search

This macro allows including long hexadecimal constants on one line, like an arbitrary extension of the .dbyt (2 byte big endian constant).

asm6

; ASM6 uses HEX, Use a Macro to convert it to use MBYT!
; Macro by Hamtaro126, under no licence.
 macro mbyt string
 hex string
 endm

ca65

; mbyt.s
; Multibyte constant macro for ca65
;
; Copyright 2013 Damian Yerrick
; Copying and distribution of this file, with or without
; modification, are permitted in any medium without royalty provided
; the copyright notice and this notice are preserved in any source
; code copies.  This file is offered as-is, without any warranty.
;
.macro mbyt_hex2nibs highnib, lownib
.local highdig, lowdig
  ; "dec0de" the hex nibbles
  .if highnib >= 'A' && highnib <= 'F'
    highdig = highnib - 'A' + 10
  .elseif highnib >= 'a' && highnib <= 'f'
    highdig = highnib - 'a' + 10
  .elseif highnib >= '0' && highnib <= '9'
    highdig = highnib - '0'
  .endif
  .if lownib >= 'A' && lownib <= 'F'
    lowdig = lownib - 'A' + 10
  .elseif lownib >= 'a' && lownib <= 'f'
    lowdig = lownib - 'a' + 10
  .elseif lownib >= '0' && lownib <= '9'
    lowdig = lownib - '0'
  .endif
  .byte highdig * $10 + lowdig
  ;.out .sprintf(".byte %02x", highdig * $10 + lowdig)
.endmacro

.macro mbyt inbytes
  ; thanks to thefox who recommended .set
  .local pos
  pos .set 0
  .out .sprintf("%s", inbytes)
  .repeat .strlen(inbytes)
    .if pos < .strlen(inbytes)
      nib .set .strat(inbytes, pos)
      ; these characters can be used as separators
      .if (nib = ' ' || nib = ',' || nib = '$' || nib = '_')
        pos .set pos + 1
      .else
        mbyt_hex2nibs nib, {.strat(inbytes, pos + 1)}
        pos .set pos + 2
      .endif
    .endif
  .endrepeat
.endmacro

; use it like this:
; mbyt "09F91102 9D74E35B D84156C5 635688C0"

Unofficial MagicKit

; Implementation of multibyte constants for Unofficial-MagicKit.
; By zzo38, Creative Commons Zero

	macro mbyt
	macset 2,4,\$1>1
	macgoto mbyt_\2
	endm

	macro mbyt_0
	endm

	macro mbyt_1
	macset 2,2,1
	macset 2,5,2
	db $\2
	mbyt_0 \>1
	macset 1,1,1
	mbyt_0 \>1
	macset 1,1,1
	macgoto mbyt
	endm

; Example:
;	mbyt 09F91102 9D74E35B D84156C5 635688C0

External links