diff --git a/src/mame/includes/dc.h b/src/mame/includes/dc.h
index 43662bde833..5d8256d7251 100644
--- a/src/mame/includes/dc.h
+++ b/src/mame/includes/dc.h
@@ -99,7 +99,12 @@ extern UINT32 dc_coin_counts[2];
 #define SB_ADST		((0x005F7818-0x005F7800)/4)
 #define SB_ADSUSP	((0x005F781c-0x005F7800)/4)
 
-
+#define SB_PDSTAP   ((0x005F7c00-0x005F7c00)/4)
+#define SB_PDSTAR   ((0x005F7c04-0x005F7c00)/4)
+#define SB_PDLEN    ((0x005F7c08-0x005F7c00)/4)
+#define SB_PDDIR    ((0x005F7c0c-0x005F7c00)/4)
+#define SB_PDTSEL   ((0x005F7c10-0x005F7c00)/4)
+#define SB_PDEN     ((0x005F7c14-0x005F7c00)/4)
 #define SB_PDST		((0x005F7c18-0x005F7c00)/4)
 
 #define RTC1		((0x00710000-0x00710000)/4)
diff --git a/src/mame/machine/dc.c b/src/mame/machine/dc.c
index d0fa766d608..e35ca8d9b89 100644
--- a/src/mame/machine/dc.c
+++ b/src/mame/machine/dc.c
@@ -893,12 +893,14 @@ WRITE64_HANDLER( dc_g2_ctrl_w )
 				UINT32 src,dst,size;
 				dst = wave_dma.aica_addr;
 				src = wave_dma.root_addr;
-				//size = wave_dma_size;
 				size = 0;
+				/* 0 rounding size = 32 Mbytes */
+				if(wave_dma.size == 0) { wave_dma.size = 0x2000000; }
+
 				/* TODO: use the ddt function. */
 				if(wave_dma.dir == 1)
 				{
-					for(;size<wave_dma.size;size++)
+					for(;size<wave_dma.size;size+=4)
 					{
 						memory_write_dword_64le(space,dst,memory_read_dword(space,src));
 						src+=4;
@@ -907,7 +909,7 @@ WRITE64_HANDLER( dc_g2_ctrl_w )
 				}
 				else
 				{
-					for(;size<wave_dma.size;size++)
+					for(;size<wave_dma.size;size+=4)
 					{
 						memory_write_dword_64le(space,src,memory_read_dword(space,dst));
 						src+=4;