# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1540927185 -3600
# Node ID b5c583edf1c296b3d9ace2d9fded90485329516d
# Parent  0338c4362083f07be1de5c993e2ce0db30627a26
Moved common VGA timings to a separate file, adjusting the visible start.

diff -r 0338c4362083 -r b5c583edf1c2 examples/vga-dual/vga.h
--- a/examples/vga-dual/vga.h	Tue Oct 30 19:23:34 2018 +0100
+++ b/examples/vga-dual/vga.h	Tue Oct 30 20:19:45 2018 +0100
@@ -20,9 +20,11 @@
 #ifndef __VGA_H__
 #define __VGA_H__
 
+#include "vga_common.h"
+
 #define LINE_LENGTH             160 /* pixels */
 #define LINE_COUNT              256 /* distinct display lines */
-#define LINE_MULTIPLIER         2
+#define LINE_MULTIPLIER         (SCANLINES / LINE_COUNT)
 
 /* 24MHz cycle measurements. */
 
@@ -31,19 +33,6 @@
 #define HSYNC_LIMIT             64
 #define HSYNC_END               (HSYNC_START + HSYNC_LIMIT)
 
-/* Horizontal lines, back porch end. */
-
-#define VISIBLE_START           70
-#define VFP_START               (VISIBLE_START + LINE_MULTIPLIER * LINE_COUNT)
-
-/* Horizontal lines, front porch end. */
-
-#define VSYNC_START             620
-
-/* Horizontal lines, back porch start. */
-
-#define VSYNC_END               622
-
 /* Framebuffer properties. */
 
 #define SCREEN_SIZE             (LINE_LENGTH * LINE_COUNT)
diff -r 0338c4362083 -r b5c583edf1c2 examples/vga-pmp/vga.h
--- a/examples/vga-pmp/vga.h	Tue Oct 30 19:23:34 2018 +0100
+++ b/examples/vga-pmp/vga.h	Tue Oct 30 20:19:45 2018 +0100
@@ -20,9 +20,11 @@
 #ifndef __VGA_H__
 #define __VGA_H__
 
+#include "vga_common.h"
+
 #define LINE_LENGTH             160 /* pixels */
 #define LINE_COUNT              256 /* distinct display lines */
-#define LINE_MULTIPLIER         2
+#define LINE_MULTIPLIER         (SCANLINES / LINE_COUNT)
 
 /* 48MHz cycle measurements. */
 
@@ -31,19 +33,6 @@
 #define HSYNC_LIMIT             128
 #define HSYNC_END               (HSYNC_START + HSYNC_LIMIT)
 
-/* Horizontal lines, back porch end. */
-
-#define VISIBLE_START           70
-#define VFP_START               (VISIBLE_START + LINE_MULTIPLIER * LINE_COUNT)
-
-/* Horizontal lines, front porch end. */
-
-#define VSYNC_START             620
-
-/* Horizontal lines, back porch start. */
-
-#define VSYNC_END               622
-
 /* Framebuffer properties. */
 
 #define SCREEN_SIZE             (LINE_LENGTH * LINE_COUNT)
diff -r 0338c4362083 -r b5c583edf1c2 examples/vga-timer/vga.h
--- a/examples/vga-timer/vga.h	Tue Oct 30 19:23:34 2018 +0100
+++ b/examples/vga-timer/vga.h	Tue Oct 30 20:19:45 2018 +0100
@@ -20,9 +20,11 @@
 #ifndef __VGA_H__
 #define __VGA_H__
 
+#include "vga_common.h"
+
 #define LINE_LENGTH             92  /* pixels */
 #define LINE_COUNT              128 /* distinct display lines */
-#define LINE_MULTIPLIER         4
+#define LINE_MULTIPLIER         (SCANLINES / LINE_COUNT)
 
 /* 24MHz cycle measurements. */
 
@@ -31,19 +33,6 @@
 #define HSYNC_LIMIT             40
 #define HSYNC_END               (HSYNC_START + HSYNC_LIMIT)
 
-/* Horizontal lines, back porch end. */
-
-#define VISIBLE_START           70
-#define VFP_START               (VISIBLE_START + LINE_MULTIPLIER * LINE_COUNT)
-
-/* Horizontal lines, front porch end. */
-
-#define VSYNC_START             620
-
-/* Horizontal lines, back porch start. */
-
-#define VSYNC_END               622
-
 /* Framebuffer properties. */
 
 #define SCREEN_SIZE             (LINE_LENGTH * LINE_COUNT)
diff -r 0338c4362083 -r b5c583edf1c2 examples/vga/vga.h
--- a/examples/vga/vga.h	Tue Oct 30 19:23:34 2018 +0100
+++ b/examples/vga/vga.h	Tue Oct 30 20:19:45 2018 +0100
@@ -20,9 +20,11 @@
 #ifndef __VGA_H__
 #define __VGA_H__
 
+#include "vga_common.h"
+
 #define LINE_LENGTH             160 /* pixels */
 #define LINE_COUNT              256 /* distinct display lines */
-#define LINE_MULTIPLIER         2
+#define LINE_MULTIPLIER         (SCANLINES / LINE_COUNT)
 
 /* 24MHz cycle measurements. */
 
@@ -31,19 +33,6 @@
 #define HSYNC_LIMIT             64
 #define HSYNC_END               (HSYNC_START + HSYNC_LIMIT)
 
-/* Horizontal lines, back porch end. */
-
-#define VISIBLE_START           70
-#define VFP_START               (VISIBLE_START + LINE_MULTIPLIER * LINE_COUNT)
-
-/* Horizontal lines, front porch end. */
-
-#define VSYNC_START             620
-
-/* Horizontal lines, back porch start. */
-
-#define VSYNC_END               622
-
 /* Framebuffer properties. */
 
 #define SCREEN_SIZE             (LINE_LENGTH * LINE_COUNT)
diff -r 0338c4362083 -r b5c583edf1c2 include/vga_common.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/vga_common.h	Tue Oct 30 20:19:45 2018 +0100
@@ -0,0 +1,43 @@
+/*
+ * Generate a VGA signal using a PIC32 microcontroller.
+ *
+ * Copyright (C) 2017, 2018 Paul Boddie <paul@boddie.org.uk>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __VGA_COMMON_H__
+#define __VGA_COMMON_H__
+
+/* Number of raster scan lines to be used. */
+
+#define SCANLINES               512
+
+/* Horizontal lines, back porch end. */
+
+#define VISIBLE_START           72
+
+/* Horizontal lines, front porch start. */
+
+#define VFP_START               (VISIBLE_START + SCANLINES)
+
+/* Horizontal lines, front porch end. */
+
+#define VSYNC_START             620
+
+/* Horizontal lines, back porch start. */
+
+#define VSYNC_END               622
+
+#endif /* __VGA_COMMON_H__ */