From 8d46476a5338a44a5e6d33f83d72e23dbf12f30e Mon Sep 17 00:00:00 2001
From: Vince Weaver <vince@deater.net>
Date: Wed, 21 Feb 2018 23:06:02 -0500
Subject: [PATCH] chiptune_player: split off bigchunk setup

---
 chiptune_player/chiptune_player.s | 32 +++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/chiptune_player/chiptune_player.s b/chiptune_player/chiptune_player.s
index af2532db..3d2db51c 100644
--- a/chiptune_player/chiptune_player.s
+++ b/chiptune_player/chiptune_player.s
@@ -123,6 +123,13 @@ mockingboard_found:
 
 	jsr	new_song
 
+
+	lda	#<CHUNK_BUFFER		; set input pointer
+	sta	INL
+	lda	#>CHUNK_BUFFER
+	sta	INH
+
+
 	;============================
 	; Enable 6502 interrupts
 	;============================
@@ -447,13 +454,27 @@ bloop3:
 	adc	#0
 	sta	LZ4_SRC+1
 
-	lda	(LZ4_SRC),Y
+	jsr	next_subsong
+
+	; should tail call
+
+	rts
+
+
+	;=================
+	; next sub-song
+	;=================
+next_subsong:
+
+	ldy	#0
+
+	lda	(LZ4_SRC),Y		; get next size value
 	sta	LZ4_END
 	iny
 	lda	(LZ4_SRC),Y
 	sta	LZ4_END+1
 
-	lda	#2
+	lda	#2			; increment pointer
 	clc
 	adc	LZ4_SRC
 	sta	LZ4_SRC
@@ -461,12 +482,7 @@ bloop3:
 	adc	#0
 	sta	LZ4_SRC+1
 
-	jsr	lz4_decode
-
-	lda	#<CHUNK_BUFFER
-	sta	INL
-	lda	#>CHUNK_BUFFER
-	sta	INH
+	jsr	lz4_decode		; decode
 
 	rts