Implemented Sound Blaster MIDI through the DSP (was surprisingly missing before). Native Windows 3.1 and NT Sound Blaster drivers can now use their DSP to drive the MIDI out.

Added MIDI out config to pre-SB16's for this new change.

src/SOUND/snd_sb_dsp.c

@@ -11,8 +11,10 @@
 #include "../dma.h"
 #include "../timer.h"
 #include "sound.h"
+#include "snd_mpu401.h"
 #include "snd_sb_dsp.h"
 
+mpu_t mpu;
 
 void pollsb(void *p);
 void sb_poll_i(void *p);
@@ -321,6 +323,29 @@ void sb_exec_command(sb_dsp_t *dsp)
                 temp = 1000000 / temp;
                 dsp->sb_freq = temp;
                 break;
+				
+				case 0x30:
+				case 0x31:
+				break;
+				
+				case 0x34:
+				dsp->uart_midi = 1;
+				dsp->uart_irq = 0;
+				break;
+				
+				case 0x35:
+				dsp->uart_midi = 1;
+				dsp->uart_irq = 1;
+				break;
+				
+				case 0x36:
+				case 0x37:
+				break;
+				
+				case 0x38:
+				dsp->onebyte_midi = 1;
+				break;				
+				
                 case 0x41: /*Set output sampling rate*/
                 case 0x42: /*Set input sampling rate*/
                 if (dsp->sb_type < SB16) break;
@@ -514,6 +539,12 @@ void sb_write(uint16_t a, uint8_t v, void *priv)
                 dsp->sbreset = v;
                 return;
                 case 0xC: /*Command/data write*/
+				if (dsp->uart_midi || dsp->onebyte_midi)
+				{
+					midi_write(v);
+					dsp->onebyte_midi = 0;
+					return;
+				}
                 timer_process();
                 dsp->wb_time = TIMER_USEC * 1;
                 dsp->wb_full = 1;
@@ -549,6 +580,10 @@ uint8_t sb_read(uint16_t a, void *priv)
         switch (a & 0xf)
         {
                 case 0xA: /*Read data*/
+				if (dsp->uart_midi)
+				{
+					return MPU401_ReadData(&mpu);
+				}
                 dsp->sbreaddat = dsp->sb_read_data[dsp->sb_read_rp];
                 if (dsp->sb_read_rp != dsp->sb_read_wp)
                 {