# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1485949250 -7200
# Node ID e7138066c7ea29e891eb20bbea3252de1e996b01
# Parent  54739a11be66dfbe19281b62b110a9f57db1bd7f
started the vdp.h header, and hastily rewrote the VDP test as C code

diff -r 54739a11be66 -r e7138066c7ea Makefile
--- a/Makefile	Tue Jan 31 07:11:17 2017 +0200
+++ b/Makefile	Wed Feb 01 13:40:50 2017 +0200
@@ -1,6 +1,7 @@
+csrc = $(wildcard src/*.c)
 asrc = $(wildcard src/*.s)
 aSsrc = $(wildcard src/*.S)
-obj = $(asrc:.s=.o) $(aSsrc:.S=.o)
+obj = $(asrc:.s=.o) $(aSsrc:.S=.o) $(csrc:.c=.o)
 
 name = test1
 elf = $(name).elf
@@ -17,7 +18,7 @@
 LD = $(tool_prefix)ld
 OBJCOPY = $(tool_prefix)objcopy
 
-CFLAGS = -m68000 -nostdinc -fno-builtin $(warn) $(dbg) $(opt) $(def)
+CFLAGS = -m68000 -fno-builtin $(warn) $(dbg) $(opt) $(def)
 CPPFLAGS = $(def)
 ASFLAGS = -m68000
 LDFLAGS = -T megadrive.ldscript -print-gc-sections
diff -r 54739a11be66 -r e7138066c7ea src/main.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main.c	Wed Feb 01 13:40:50 2017 +0200
@@ -0,0 +1,12 @@
+#include "vdp.h"
+
+int main(void)
+{
+	VDP_PORT_CTL = 0xc000;
+	VDP_PORT_CTL = 0;
+	VDP_PORT_DATA = 0x1f8;
+	VDP_PORT_CTL = 0x8700;
+	VDP_PORT_CTL = 0x8004;
+	VDP_PORT_CTL = 0x8144;
+	return 0;
+}
diff -r 54739a11be66 -r e7138066c7ea src/main.s
--- a/src/main.s	Tue Jan 31 07:11:17 2017 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,12 +0,0 @@
-	.text
-	.global main
-main:
-	move.l #0xc00000, %a0
-	move.l #0xc00004, %a1
-	move.w #0xc000, (%a1)
-	move.w #0, (%a1)
-	move.w #0x1f8, (%a0)
-	move.w #0x8700, (%a1)	| set bg color to 0
-	move.w #0x8004, (%a1)
-	move.w #0x8144, (%a1)	| enable display 
-	rts
diff -r 54739a11be66 -r e7138066c7ea src/vdp.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vdp.h	Wed Feb 01 13:40:50 2017 +0200
@@ -0,0 +1,41 @@
+#ifndef VDP_H_
+#define VDP_H_
+
+#include <stdint.h>
+
+#define VDP_PORT_DATA		(*(volatile uint16_t*)0xc00000)
+#define VDP_PORT_DATA32		(*(volatile uint32_t*)0xc00000)
+#define VDP_PORT_CTL		(*(volatile uint16_t*)0xc00004)
+#define VDP_PORT_CTL32		(*(volatile uint32_t*)0xc00004)
+#define VDP_PORT_HVCOUNT	(*(volatile uint16_t*)0xc00008)
+#define VDP_PORT_PSG		(*(volatile uint16_t*)0xc00010)
+
+/* control register read flags */
+#define VDP_CTL_PAL_BIT			0x0001
+#define VDP_CTL_HBLANK_BIT		0x0002
+#define VDP_CTL_VBLANK_BIT		0x0004
+#define VDP_CTL_DT3_BIT			0x0008
+#define VDP_CTL_ODD_FRAME_BIT	0x0010
+#define VDP_CTL_COLIDE_BIT		0x0020
+#define VDP_CTL_SPRITE_OVF_BIT	0x0040
+#define VDP_CTL_FRAME_BIT		0x0080
+#define VDP_CTL_FIFO_FULL_BIT	0x0100
+#define VDP_CTL_FIFO_EMPTY_BIT	0x0200
+
+/* control register write flags (RSET) */
+#define VDP_CTL_REGSEL_MASK		0x1f00
+#define VDP_CTL_DATA_MASK		0x00ff
+
+#define VDP_RSET(reg, val)	\
+	(0x8000 | (VDP_CTL_REGSEL_MASK & ((uint16_t)(reg) << 8)) | \
+	 (VDP_CTL_DATA_MASK & (uint16_t)(val)))
+
+#define VDP_MODE_WR_BIT		1
+
+#define VDP_VRAM_WR		1
+#define VDP_CRAM_WR		3
+
+#define VDP_ADDRSET(addr, mode) /* TODO */
+
+
+#endif	/* VDP_H_ */