From 23bdc734bbbd38d6bae573635d4638c3e755928d Mon Sep 17 00:00:00 2001
From: greg <elorian.mestec@gmail.com>
Date: Wed, 14 Dec 2016 11:05:38 -0800
Subject: [PATCH] Trying to get VRAM DMA to work

For tile map
---
 test_gfx.asm | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/test_gfx.asm b/test_gfx.asm
index 43624f8..6a783a1 100644
--- a/test_gfx.asm
+++ b/test_gfx.asm
@@ -26,7 +26,7 @@ VBlank:
     Video_Port_Control
 
     ldx #DEST
-    stx $2116 ; $2116/2117 is 2byte address for VRAM upload/download. most significant bit must be 0 
+    stx $2116 ; $2116/2117 is 2byte address for VRAM upload/download. most significant bit must be 0
 
     lda #:SOURCE ; source bank
     ldx #SOURCE ; source offset
@@ -64,7 +64,6 @@ Start:
 
     ; size (last argument) depends on color mode
     ; location is beginning of VRAM
-    Load_Block_to_VRAM Tiles, $0000, (8*2*2),
 
     ; put character data at VRAM $0000, tile data at $0400
     lda #$04
@@ -72,10 +71,15 @@ Start:
     lda #$00
     sta $210b ; BG1 character location ($1000 word intervals - can't go over $8000 b/c size of VRAM)
 
+    stz $1337
+
     ; main screen designation
     lda #%00000001
     sta $212c ; enable bkg 1,
 
+;    Load_Block_to_VRAM TileMap, $0400, 16
+    Load_Block_to_VRAM Tiles, $0000, (8*2*2),
+
     ldx #$0400 ; load $0400 (VRAM address of tile data)
 TileLoadLoop:
 
@@ -95,7 +99,6 @@ TileLoadLoop:
     cpx #$0780 ; $400 - $780 seems to be limit of snes screen tile memory
     bne TileLoadLoop
 
-
 lda #%10000001  ; enable NMI and joypads
 sta $4200
 
@@ -156,4 +159,14 @@ Tiles:
     .db %00111100
     .db %00111100
 
+TileMap:
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+    .db $00, $01
+
 .ENDS