From 6787fb362f9388d193596ef99e86ee4700dac7de Mon Sep 17 00:00:00 2001
From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Thu, 10 Apr 2008 20:12:20 +0000
Subject: [PATCH] New get_tv module from Stefan Haubenthal.

git-svn-id: svn://svn.cc65.org/cc65/trunk@3830 b7a2c559-68d2-44c3-8de9-860c34a00d81
---
 libsrc/nes/Makefile |  1 +
 libsrc/nes/get_tv.s | 37 +++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 libsrc/nes/get_tv.s

diff --git a/libsrc/nes/Makefile b/libsrc/nes/Makefile
index 6e9333c30..191f4bb06 100644
--- a/libsrc/nes/Makefile
+++ b/libsrc/nes/Makefile
@@ -54,6 +54,7 @@ OBJS =  _scrsize.o      \
         crt0.o          \
         ctype.o         \
         cvline.o        \
+        get_tv.o        \
         gotox.o         \
         gotoxy.o        \
         gotoy.o         \
diff --git a/libsrc/nes/get_tv.s b/libsrc/nes/get_tv.s
new file mode 100644
index 000000000..a82953c81
--- /dev/null
+++ b/libsrc/nes/get_tv.s
@@ -0,0 +1,37 @@
+;
+; Stefan Haubenthal, 2007-01-21
+;
+; unsigned char __fastcall__ get_tv (void);
+; /* Return the video mode the machine is using */
+;
+
+	.include	"nes.inc"
+	.include	"get_tv.inc"
+	.importzp	tmp1, tmp2
+
+;--------------------------------------------------------------------------
+; _get_tv
+
+.proc	_get_tv
+
+	lda	#TV::NTSC	; assume NTSC
+	tax			; clear
+	sta	tmp1
+	sta	tmp2
+	ldy	tickcount
+wait:	cpy	tickcount
+	beq	wait
+	iny			; next tick
+loop:	cpy	tickcount
+	bne	over
+	inc	tmp1
+	bne	loop
+	inc	tmp2
+	bne	loop
+over:	ldy	tmp2
+	cpy	#9
+	bcc	nopal
+	lda	#TV::PAL	; choose PAL
+nopal:	rts
+
+.endproc
-- 
2.39.5