Added the NCR 53C810 PCI SCSI controller;

Fixed the behavior of the CD-ROM GET CONFIGURATION command when unimplemented features are requested;
Fixed the behavior of the CD-ROM READ DVD STRUCTURE command in some situations and made it correctly report 05/30/02 for incompatible format;
Reworked the PS/2 Model 80 Type 2 memory handling a bit;
The emulator now allocates the few MB of space needed for pages for the entire 4 GB RAM space at the startup and only memset's it to 0 on hard reset - should make sure DMA page reads from/writes to memory-mapped devices no longer crash the emulator on invalidating the memory range;
Applied app applicable PCem patches;
The PS/1 Model 2133 now also applies PS/2-style NMI mask handling - fixes the 486 recompiler on this machine;
Added the missing #include of "cpu/cpu.h" in io.c, fixes compiling when I/O tracing is enabled.

src/sound/openal.c

@@ -1,3 +1,4 @@
+#include <math.h>
 #include <stdio.h>
 #include <stdint.h>
 #include <string.h>
@@ -205,6 +206,7 @@ void givealbuffer_common(void *buf, uint8_t src, int size, int freq)
     int processed;
     int state;
     ALuint buffer;
+    double gain;
 
         alGetSourcei(source[src], AL_SOURCE_STATE, &state);
 
@@ -216,6 +218,10 @@ void givealbuffer_common(void *buf, uint8_t src, int size, int freq)
 
         if (processed>=1)
         {
+                gain = pow(10.0, (double)sound_gain[src] / 20.0);
+                
+                // alSourcef(source[src], AL_GAIN, gain);
+
                 alSourceUnqueueBuffers(source[src], 1, &buffer);
 
 		if (sound_is_float)

src/sound/sound.c

@@ -8,7 +8,7 @@
  *
  *		Sound emulation core.
  *
- * Version:	@(#)sound.c	1.0.9	2017/12/05
+ * Version:	@(#)sound.c	1.0.10	2017/12/09
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -52,6 +52,7 @@ typedef struct {
 int sound_card_current = 0;
 int sound_pos_global = 0;
 int soundon = 1;
+int sound_gain[3] = { 0, 0, 0 };
 
 
 static int sound_card_last = 0;

src/sound/sound.h

@@ -8,7 +8,7 @@
  *
  *		Sound emulation core.
  *
- * Version:	@(#)sound.h	1.0.2	2017/10/04
+ * Version:	@(#)sound.h	1.0.3	2017/12/09
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -20,6 +20,8 @@
 # define EMU_SOUND_H
 
 
+extern int sound_gain[3];
+
 #define SOUNDBUFLEN	(48000/50)
 
 #define CD_FREQ		44100