diff --git a/firmware/scroll/Makefile b/firmware/scroll/Makefile
index 2d43673..0a647a8 100644
--- a/firmware/scroll/Makefile
+++ b/firmware/scroll/Makefile
@@ -13,16 +13,18 @@
 
 include ../../sdk/common.mk
 
+INCLUDEDIR	= ../../sdk/include
 FUENTEABIN	= tools/build/FuenteABin$(EXESUFFIX)
 AS		= sjasmplus
 ifeq ($(USE_SJASMPLUS_VERSION),sjasmplus)
+$(error Original SJAsmPlus is not supported for now - use version by `z00m128')
 AFLAGS		= --nobanner
 else ifeq ($(USE_SJASMPLUS_VERSION),z00m128)
 AFLAGS		= --nologo
 else
 AFLAGS		=
 endif
-AFLAGS		+= -I../../sdk/include
+AFLAGS		+= -I$(INCLUDEDIR)
 
 .PHONY: all
 all: scroll.tap
@@ -33,17 +35,24 @@ scroll.tap: scrolldesc.bin
 scrolldesc.bin: scrolldesc.asm define.asm scroll.bin.zx7b
 	$(AS) $(AFLAGS) --raw=$@ $<
 
-define.asm: scroll.bin
+define.asm: scroll.bin scroll.exp
 	echo ' define filesize $(shell stat -c %s $<)' >$@
+	cat scroll.exp >>$@
 
 scroll.bin.zx7b: scroll.bin
 	zx7b $< $@
 
-scroll.bin: scroll.asm string.asm music.bin fuente6x8.bin lineas.asm fondo.rcs
-	$(AS) $(AFLAGS) --raw=$@ $<
-
-music.bin: playstc.bin music.stc
-	cat $^ >$@
+scroll.bin scroll.exp:\
+ scroll.asm\
+ string.asm\
+ $(INCLUDEDIR)/playstc.inc\
+ $(INCLUDEDIR)/filestc.def\
+ $(INCLUDEDIR)/ay.def\
+ music.stc\
+ fuente6x8.bin\
+ lineas.asm\
+ fondo.rcs
+	$(AS) $(AFLAGS) --raw=scroll.bin --exp=scroll.exp $<
 
 fuente6x8.bin: fuente6x8.png | $(FUENTEABIN)
 	$(FUENTEABIN) $< $@
@@ -67,7 +76,7 @@ uninstall:;
 .PHONY: clean
 clean: | tools
 	$(MAKE) -w -C $| $@
-	rm -f music.bin fuente6x8.bin fondo.rcs scroll.bin scroll.bin.zx7b define.asm scrolldesc.bin scroll.tap
+	rm -f fuente6x8.bin fondo.rcs scroll.bin scroll.exp scroll.bin.zx7b define.asm scrolldesc.bin scroll.tap
 
 .PHONY: distclean
 distclean:;
diff --git a/firmware/scroll/scroll.asm b/firmware/scroll/scroll.asm
index 9a1f426..4ea24cf 100644
--- a/firmware/scroll/scroll.asm
+++ b/firmware/scroll/scroll.asm
@@ -27,12 +27,26 @@
 ;   SJAsmPlus, <https://github.com/sjasmplus/sjasmplus/>
 
         output  scroll.bin
+
         org     $5e6d
-  display $6d35+string-music
+
+        export  filestart
+        export  start
+
+filestart
 string  include string.asm
-music   ld      (vari+2), ix
-        incbin  music.bin
+
+music   ld      (vari), ix
+        jp      PlaySTC.Play
+
+        define  PLAYSTC_AY_FREQUENCY ay_freq_Spectrum
+        define  PLAYSTC_USER_DEFINED_FILE 0
+        include playstc.inc
+
+track   incbin  music.stc
+
 fuente  incbin  fuente6x8.bin
+
 start   ld      hl, $c000
         ld      de, $c001
         ld      bc, $017f
@@ -116,9 +130,9 @@ start2  ld      a, (hl)
         jr      nc, start1
         ld      a, $c9
         ld      ($c006), a
-        ld      hl, $716f
-        call    music+7
-start3  call    $6e77
+        ld      hl, track
+        call    PlaySTC.Init
+start3  call    PlaySTC.Play
         ei
         halt
         di
@@ -141,7 +155,8 @@ start4  djnz    start4
         push    hl
         push    hl
         ld      sp, hl
-vari    ld      ix, string
+        ld      ix, string
+vari: equ $-2
         ld      hl, start3
         push    hl
         ld      hl, music
diff --git a/firmware/scroll/scrolldesc.asm b/firmware/scroll/scrolldesc.asm
index 3d3f584..3a02e5f 100644
--- a/firmware/scroll/scrolldesc.asm
+++ b/firmware/scroll/scrolldesc.asm
@@ -10,7 +10,7 @@
         include define.asm
         output  scrolldesc.bin
         org     $5ccb
-        ld      de, $5e6d+filesize-1
+        ld      de, filestart+filesize-1
         di
         defb    $de, $c0, $37, $0e, $8f, $39, $96
         jr      aqui
@@ -63,6 +63,6 @@ offend  rr      e
         lddr
 exitdz  pop     hl
         jr      nc, mainlo
-        jp      $7be4
+        jp      start
         incbin  scroll.bin.zx7b
 fin