ASM GB-Decompress version

gb-decompress/ASM/rle_decompress.h

@@ -0,0 +1,9 @@
+// GB-Compress decompressor
+// Compatible with GBTD
+
+#ifndef __RLE_DECOMPRESS_H_INCLUDE
+#define __RLE_DECOMPRESS_H_INCLUDE
+
+void gb_decompress(const unsigned char * sour, unsigned char * dest);
+
+#endif

gb-decompress/ASM/rle_decompress.s

@@ -0,0 +1,93 @@
+; GB-Compress decompressor
+; Compatible with GBTD
+
+.area _CODE
+_gb_decompress::
+        lda     hl,5(SP)
+        ld      a,(hl-)
+        ld      d,a
+        ld      a,(hl-)
+        ld      e,a
+        ld      a,(hl-)
+        ld      l,(hl)
+        ld      h,a
+
+; hl = source; de = dest
+gb_decompress::
+        push    bc
+1$:
+        ld      a,(hl+) ; load command
+        or      a
+        jr      z,9$    ; exit, if last byte
+        bit     7,a
+        jr      nz,5$   ; string functions
+        bit     6,a
+        jr      nz,3$
+        ; RLE byte
+        and     #63     ; calc counter
+        inc     a
+        ld      b,a
+        ld      a,(hl+)
+2$:
+        ld      (de),a
+        inc     de
+        dec     b
+        jr      nz,2$
+        jr      1$      ; next command
+3$:                     ; RLE word
+        and     #63
+        inc     a
+        ld      b,(hl)  ; load word into bc
+        inc     hl
+        ld      c,(hl)
+        inc     hl
+4$:
+        push    af
+        ld      a,b     ; store word
+        ld      (de),a
+        inc     de
+        ld      a,c
+        ld      (de),a
+        inc     de
+        pop     af
+        dec     a
+        jr      nz,4$
+        jr      1$      ; next command
+5$:
+        bit     6,a
+        jr      nz,7$
+        ; string repeat
+        and     a,#63
+        inc     a
+        push    hl
+        ld      c,(hl)
+        inc     hl
+        ld      b,(hl)
+        ld      h,d
+        ld      l,e
+        add     hl,bc
+        ld      b,a
+6$:
+        ld      a,(hl+)
+        ld      (de),a
+        inc     de
+        dec     b
+        jr      nz,6$
+        pop     hl
+        inc     hl
+        inc     hl
+        jr      1$      ; next command
+7$:                     ; string copy
+        and     #63
+        inc     a
+        ld      b,a
+8$:                    
+        ld      a,(hl+)
+        ld      (de),a
+        inc     de
+        dec     b
+        jr      nz,8$
+        jr      1$      ; next command
+9$:
+        pop     bc
+        ret

gbdk/rle_decompress.c → gb-decompress/C/rle_decompress.c

@@ -1,4 +1,7 @@
-void decompress(const unsigned char * sour, unsigned char * dest) __naked {
+// GB-Compress decompressor
+// Compatible with GBTD
+
+void gb_decompress(const unsigned char * sour, unsigned char * dest) __naked {
     sour; dest;
 __asm   
         lda     hl,5(SP)

gb-decompress/C/rle_decompress.h

@@ -0,0 +1,9 @@
+// GB-Compress decompressor
+// Compatible with GBTD
+
+#ifndef __RLE_DECOMPRESS_H_INCLUDE
+#define __RLE_DECOMPRESS_H_INCLUDE
+
+void gb_decompress(const unsigned char * sour, unsigned char * dest);
+
+#endif