Increase MIDI FIFO buffer size for SCSP; should prevent FIFO overflows

Also use similar macro for DSB FIFO buffer

Src/Model3/DSB.cpp

@@ -376,7 +376,7 @@ UINT8 CDSB1::IORead8(UINT32 addr)
 		if (fifoIdxR != fifoIdxW)	// if these are equal, nothing has been written yet (don't advance)
 		{
 			fifoIdxR++;
-			fifoIdxR &= 127;
+			fifoIdxR &= FIFO_STACK_SIZE_MASK;
 		}
 
 		if (fifoIdxR == fifoIdxW)	// FIFO empty?
@@ -415,7 +415,7 @@ void CDSB1::SendCommand(UINT8 data)
 	 * over the course of a frame at once.
 	 */
 	fifo[fifoIdxW++] = data;
-	fifoIdxW &= 127;
+	fifoIdxW &= FIFO_STACK_SIZE_MASK;
 	//printf("Write FIFO: %02X\n", data);
 
 	// Have we caught up to the read pointer?
@@ -983,7 +983,7 @@ void CDSB2::SendCommand(UINT8 data)
 	 * over the course of a frame at once.
 	 */
 	fifo[fifoIdxW++] = data;
-	fifoIdxW &= 255;
+	fifoIdxW &= FIFO_STACK_SIZE_MASK;
 	//printf("Write FIFO: %02X\n", data);
 
 	// Have we caught up to the read pointer?
@@ -1013,7 +1013,7 @@ void CDSB2::RunFrame(INT16 *audioL, INT16 *audioR)
   {
     cmdLatch = fifo[fifoIdxR];	// retrieve next command byte
     fifoIdxR++;
-    fifoIdxR &= 255;
+    fifoIdxR &= FIFO_STACK_SIZE_MASK;
 
     M68KSetIRQ(1);	// indicate pending command
     //printf("68K INT fired\n");

Src/Model3/DSB.h

@@ -38,6 +38,8 @@
 #include "CPU/Z80/Z80.h"
 #include "Util/NewConfig.h"
 
+#define FIFO_STACK_SIZE			0x100
+#define FIFO_STACK_SIZE_MASK	(FIFO_STACK_SIZE - 1)
 
 /******************************************************************************
  Resampling
@@ -213,7 +215,7 @@ private:
 	UINT8		*ram;			// Z80 RAM
 
 	// Command FIFO
-	UINT8	fifo[128];
+	UINT8	fifo[FIFO_STACK_SIZE];
 	int		fifoIdxR;		// read position
 	int		fifoIdxW;		// write position
 
@@ -301,7 +303,7 @@ private:
 	UINT8		*ram;			// 68K RAM
 
 	// Command FIFO
-	UINT8	fifo[256];
+	UINT8	fifo[FIFO_STACK_SIZE];
 	int		fifoIdxR;		// read position
 	int		fifoIdxW;		// write position
 

Src/Sound/SCSP.cpp

@@ -134,7 +134,7 @@ static DWORD IrqMidi;
 unsigned short MCIEB;
 unsigned short MCIPD;
 
-#define MIDI_STACK_SIZE			128
+#define MIDI_STACK_SIZE			0x100
 #define MIDI_STACK_SIZE_MASK	(MIDI_STACK_SIZE-1)
 
 static BYTE MidiOutStack[16];