[stm32f429i-discovery] Added LTDC DMA example.

This example is just using buffers and built in alpha overlay
functionality to animate a dmond floating on a checker board. After
initializing of the frame buffers only 7 registers are being modified to
implement the animation.

examples/stm32/f4/stm32f429i-discovery/lcd-dma/sdram.h

@@ -0,0 +1,32 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2014 Chuck McManis <cmcmanis@mcmanis.com>
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __SDRAM_H
+#define __SDRAM_H
+
+#define SDRAM_BASE_ADDRESS ((uint8_t *)(0xd0000000))
+
+/* Initialize the SDRAM chip on the board */
+void sdram_init(void);
+
+#ifndef NULL
+#define NULL	(void *)(0)
+#endif
+
+#endif