From 7d788578b2cfe454d5c266552411820b50075d08 Mon Sep 17 00:00:00 2001
From: Nebuleon Fumika
Date: Sun, 20 Jan 2013 22:26:24 -0500
Subject: Initial 8-bit sound commit. For the lulz!

---
 source/nds/entry.cpp |   2 +-
 source/snes9x.h      |   2 +-
 source/soundux.cpp   | 132 +++++++++++++++++++++++++++++++--------------------
 source/soundux.h     |   2 +
 4 files changed, 84 insertions(+), 54 deletions(-)

diff --git a/source/nds/entry.cpp b/source/nds/entry.cpp
index 8cd5c06..792608a 100644
--- a/source/nds/entry.cpp
+++ b/source/nds/entry.cpp
@@ -370,6 +370,7 @@ void init_sfc_setting(void)
 	//sound settings
     Settings.APUEnabled = Settings.NextAPUEnabled = TRUE;
 	Settings.FixFrequency = 1;
+	S9xSetEightBitConsoleSound (TRUE);
 
 
     Settings.H_Max = SNES_CYCLES_PER_SCANLINE;
@@ -377,7 +378,6 @@ void init_sfc_setting(void)
     Settings.ShutdownMaster = TRUE;
     Settings.FrameTimePAL = 20000;
     Settings.FrameTimeNTSC = 16667;
-    Settings.DisableSampleCaching = FALSE;
     Settings.DisableMasterVolume = FALSE;
     Settings.Mouse = TRUE;
     Settings.SuperScope = TRUE;
diff --git a/source/snes9x.h b/source/snes9x.h
index 6c93855..ab70efa 100644
--- a/source/snes9x.h
+++ b/source/snes9x.h
@@ -337,11 +337,11 @@ struct SSettings{
 #ifndef FOREVER_16_BIT_SOUND
     bool8  SixteenBitSound;
 #endif
+    bool8  EightBitConsoleSound;  // due to caching, this needs S9xSetEightBitConsoleSound()
     int    SoundBufferSize;
     int    SoundMixInterval;
     bool8  SoundEnvelopeHeightReading;
     bool8  DisableSoundEcho;
-    bool8  DisableSampleCaching;
     bool8  DisableMasterVolume;
     bool8  SoundSync;
     bool8  InterpolatedSound;
diff --git a/source/soundux.cpp b/source/soundux.cpp
index acddd0a..45e303b 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -166,6 +166,21 @@ extern "C" void DecodeBlockAsm2 (int8 *, int16 *, int32 *, int32 *);
 #define LAST_SAMPLE 0xffffff
 #define JUST_PLAYED_LAST_SAMPLE(c) ((c)->sample_pointer >= LAST_SAMPLE)
 
+const int16 SQUARE_WAVE_SAMPLE[16] = {32767, 32767, 32767, 32767, 32767, 32767, 32767, 32767, -32768, -32768, -32768, -32768, -32768, -32768, -32768, -32768,};
+
+void S9xSetEightBitConsoleSound (bool8 Enabled)
+{
+	if (Settings.EightBitConsoleSound != Enabled)
+	{
+		Settings.EightBitConsoleSound = Enabled;
+		int i;
+		for (i = 0; i < 8; i++)
+		{
+			SoundData.channels[i].needs_decode = TRUE;
+		}
+	}
+}
+
 STATIC inline uint8 *S9xGetSampleAddress (int sample_number)
 {
     uint32 addr = (((APU.DSP[APU_DIR] << 8) + (sample_number << 2)) & 0xffff);
@@ -804,7 +819,7 @@ void DecodeBlock (Channel *ch)
     signed char sample1, sample2;
     unsigned char i;
     bool invalid_header;
-	
+
     if (Settings.AltSampleDecode)
     {
 		if (Settings.AltSampleDecode < 3)
@@ -820,74 +835,87 @@ void DecodeBlock (Channel *ch)
 		ch->block = ch->decoded;
 		return;
     }
-    signed char *compressed = (signed char *) &IAPU.RAM [ch->block_pointer];
+
+	if (Settings.EightBitConsoleSound)
+	{
+		signed char *compressed = (signed char *) &IAPU.RAM [ch->block_pointer];
+
+		filter = *compressed;
+		if ((ch->last_block = filter & 1))
+			ch->loop = (filter & 2) != 0;
+		ch->block = ch->decoded;
+		memcpy(ch->decoded, SQUARE_WAVE_SAMPLE, sizeof(SQUARE_WAVE_SAMPLE));
+	}
+	else
+	{
+	    signed char *compressed = (signed char *) &IAPU.RAM [ch->block_pointer];
 	
-    filter = *compressed;
-    if ((ch->last_block = filter & 1))
-		ch->loop = (filter & 2) != 0;
+	    filter = *compressed;
+	    if ((ch->last_block = filter & 1))
+			ch->loop = (filter & 2) != 0;
 	
-	compressed++;
-	signed short *raw = ch->block = ch->decoded;
+		compressed++;
+		signed short *raw = ch->block = ch->decoded;
 	
-	// Seperate out the header parts used for decoding
+		// Seperate out the header parts used for decoding
 
-	shift = filter >> 4;
+		shift = filter >> 4;
 	
-	// Header validity check: if range(shift) is over 12, ignore
-	// all bits of the data for that block except for the sign bit of each
-	invalid_header = (shift >= 0xD);
+		// Header validity check: if range(shift) is over 12, ignore
+		// all bits of the data for that block except for the sign bit of each
+		invalid_header = (shift >= 0xD);
 
-	filter = filter&0x0c;
+		filter = filter&0x0c;
 
-	int32 prev0 = ch->previous [0];
-	int32 prev1 = ch->previous [1];
+		int32 prev0 = ch->previous [0];
+		int32 prev1 = ch->previous [1];
 	
-	for (i = 8; i != 0; i--)
-	{
-		sample1 = *compressed++;
-		sample2 = sample1 << 4;
-		//Sample 2 = Bottom Nibble, Sign Extended.
-		sample2 >>= 4;
-		//Sample 1 = Top Nibble, shifted down and Sign Extended.
-		sample1 >>= 4;
-			if (invalid_header) { sample1>>=3; sample2>>=3; }
+		for (i = 8; i != 0; i--)
+		{
+			sample1 = *compressed++;
+			sample2 = sample1 << 4;
+			//Sample 2 = Bottom Nibble, Sign Extended.
+			sample2 >>= 4;
+			//Sample 1 = Top Nibble, shifted down and Sign Extended.
+			sample1 >>= 4;
+				if (invalid_header) { sample1>>=3; sample2>>=3; }
 		
-		for (int nybblesmp = 0; nybblesmp<2; nybblesmp++){
-			out=(((nybblesmp) ? sample2 : sample1) << shift);
-			out >>= 1;
+			for (int nybblesmp = 0; nybblesmp<2; nybblesmp++){
+				out=(((nybblesmp) ? sample2 : sample1) << shift);
+				out >>= 1;
 			
-			switch(filter)
-			{
-				case 0x00:
-					// Method0 - [Smp]
-					break;
+				switch(filter)
+				{
+					case 0x00:
+						// Method0 - [Smp]
+						break;
 				
-				case 0x04:
-					// Method1 - [Delta]+[Smp-1](15/16)
-					out+=(prev0>>1)+((-prev0)>>5);
-					break;
+					case 0x04:
+						// Method1 - [Delta]+[Smp-1](15/16)
+						out+=(prev0>>1)+((-prev0)>>5);
+						break;
 				
-				case 0x08:
-					// Method2 - [Delta]+[Smp-1](61/32)-[Smp-2](15/16)
-					out+=(prev0)+((-(prev0 +(prev0>>1)))>>5)-(prev1>>1)+(prev1>>5);
-					break;
+					case 0x08:
+						// Method2 - [Delta]+[Smp-1](61/32)-[Smp-2](15/16)
+						out+=(prev0)+((-(prev0 +(prev0>>1)))>>5)-(prev1>>1)+(prev1>>5);
+						break;
 				
-				default:
-					// Method3 - [Delta]+[Smp-1](115/64)-[Smp-2](13/16)
-					out+=(prev0)+((-(prev0 + (prev0<<2) + (prev0<<3)))>>7)-(prev1>>1)+((prev1+(prev1>>1))>>4);
-					break;
+					default:
+						// Method3 - [Delta]+[Smp-1](115/64)-[Smp-2](13/16)
+						out+=(prev0)+((-(prev0 + (prev0<<2) + (prev0<<3)))>>7)-(prev1>>1)+((prev1+(prev1>>1))>>4);
+						break;
 				
+				}
+				CLIP16(out);
+					*raw++ = (signed short)(out<<1);
+				prev1=(signed short)prev0;
+				prev0=(signed short)(out<<1);
 			}
-			CLIP16(out);
-				*raw++ = (signed short)(out<<1);
-			prev1=(signed short)prev0;
-			prev0=(signed short)(out<<1);
 		}
+		ch->previous [0] = prev0;
+		ch->previous [1] = prev1;
 	}
-	ch->previous [0] = prev0;
-	ch->previous [1] = prev1;
-	
-    ch->block_pointer += 9;
+	ch->block_pointer += 9;
 }
 
 
diff --git a/source/soundux.h b/source/soundux.h
index 8fb8396..224d24a 100644
--- a/source/soundux.h
+++ b/source/soundux.h
@@ -220,6 +220,8 @@ typedef struct
 
 EXTERN_C SSoundData SoundData;
 
+void S9xSetEightBitConsoleSound (bool8 Enabled);
+
 void S9xSetSoundVolume (int channel, short volume_left, short volume_right);
 void S9xSetSoundFrequency (int channel, int hertz);
 void S9xSetSoundHertz (int channel, int hertz);
-- 
cgit v1.2.3


From 40596a7d6810c2d3bc2db28e8f9c2b825972d21d Mon Sep 17 00:00:00 2001
From: Nebuleon Fumika
Date: Mon, 21 Jan 2013 22:35:21 -0500
Subject: Triangle wave ALL the channels!

---
 source/soundux.cpp | 94 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 86 insertions(+), 8 deletions(-)

diff --git a/source/soundux.cpp b/source/soundux.cpp
index 45e303b..a3103e7 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -166,8 +166,6 @@ extern "C" void DecodeBlockAsm2 (int8 *, int16 *, int32 *, int32 *);
 #define LAST_SAMPLE 0xffffff
 #define JUST_PLAYED_LAST_SAMPLE(c) ((c)->sample_pointer >= LAST_SAMPLE)
 
-const int16 SQUARE_WAVE_SAMPLE[16] = {32767, 32767, 32767, 32767, 32767, 32767, 32767, 32767, -32768, -32768, -32768, -32768, -32768, -32768, -32768, -32768,};
-
 void S9xSetEightBitConsoleSound (bool8 Enabled)
 {
 	if (Settings.EightBitConsoleSound != Enabled)
@@ -838,13 +836,93 @@ void DecodeBlock (Channel *ch)
 
 	if (Settings.EightBitConsoleSound)
 	{
-		signed char *compressed = (signed char *) &IAPU.RAM [ch->block_pointer];
-
-		filter = *compressed;
-		if ((ch->last_block = filter & 1))
+	    signed char *compressed = (signed char *) &IAPU.RAM [ch->block_pointer];
+	
+	    filter = *compressed;
+	    if ((ch->last_block = filter & 1))
 			ch->loop = (filter & 2) != 0;
-		ch->block = ch->decoded;
-		memcpy(ch->decoded, SQUARE_WAVE_SAMPLE, sizeof(SQUARE_WAVE_SAMPLE));
+	
+		compressed++;
+		signed short *raw = ch->block = ch->decoded;
+	
+		// Seperate out the header parts used for decoding
+
+		shift = filter >> 4;
+	
+		// Header validity check: if range(shift) is over 12, ignore
+		// all bits of the data for that block except for the sign bit of each
+		invalid_header = (shift >= 0xD);
+
+		filter = filter&0x0c;
+
+		int32 prev0 = ch->previous [0];
+		int32 prev1 = ch->previous [1];
+
+		int16 amplitude = 0;
+	
+		for (i = 8; i != 0; i--)
+		{
+			sample1 = *compressed++;
+			sample2 = sample1 << 4;
+			//Sample 2 = Bottom Nibble, Sign Extended.
+			sample2 >>= 4;
+			//Sample 1 = Top Nibble, shifted down and Sign Extended.
+			sample1 >>= 4;
+				if (invalid_header) { sample1>>=3; sample2>>=3; }
+		
+			for (int nybblesmp = 0; nybblesmp<2; nybblesmp++){
+				out=(((nybblesmp) ? sample2 : sample1) << shift);
+				out >>= 1;
+			
+				switch(filter)
+				{
+					case 0x00:
+						// Method0 - [Smp]
+						break;
+				
+					case 0x04:
+						// Method1 - [Delta]+[Smp-1](15/16)
+						out+=(prev0>>1)+((-prev0)>>5);
+						break;
+				
+					case 0x08:
+						// Method2 - [Delta]+[Smp-1](61/32)-[Smp-2](15/16)
+						out+=(prev0)+((-(prev0 +(prev0>>1)))>>5)-(prev1>>1)+(prev1>>5);
+						break;
+				
+					default:
+						// Method3 - [Delta]+[Smp-1](115/64)-[Smp-2](13/16)
+						out+=(prev0)+((-(prev0 + (prev0<<2) + (prev0<<3)))>>7)-(prev1>>1)+((prev1+(prev1>>1))>>4);
+						break;
+				
+				}
+				CLIP16(out);
+				int16 result = (signed short)(out<<1);
+				if (abs(result) > amplitude)
+					amplitude = abs(result);
+				prev1=(signed short)prev0;
+				prev0=(signed short)(out<<1);
+			}
+		}
+		ch->previous [0] = prev0;
+		ch->previous [1] = prev1;
+		// Make it a square wave with an amplitude equivalent to that
+		// of the highest amplitude sample of the block.
+		/* for (i = 0; i < 8; i++)
+			ch->decoded[i] = amplitude;
+		for (i = 8; i < 16; i++)
+			ch->decoded[i] = -amplitude; */
+		// Make it a triangle wave with an amplitude equivalent to that
+		// of the highest amplitude sample of the block.
+		ch->decoded[0] =  ch->decoded[8]  = 0;
+		ch->decoded[1] =  ch->decoded[7]  = amplitude / 4;
+		ch->decoded[2] =  ch->decoded[6]  = amplitude / 2;
+		ch->decoded[3] =  ch->decoded[5]  = amplitude * 3 / 4;
+		ch->decoded[4] =  amplitude;
+		ch->decoded[9] =  ch->decoded[15] = -(amplitude / 4);
+		ch->decoded[10] = ch->decoded[14] = -(amplitude / 2);
+		ch->decoded[11] = ch->decoded[13] = -(amplitude * 3 / 4);
+		ch->decoded[12] = -amplitude;
 	}
 	else
 	{
-- 
cgit v1.2.3


From 0a2041d1ce3a5ce62df279371ce6857bb8b11205 Mon Sep 17 00:00:00 2001
From: Nebuleon Fumika
Date: Fri, 8 Feb 2013 05:50:37 -0500
Subject: Add square waves for waves not matching sines or triangles. Add noise
 for drums exceeding a certain "randomness" threshold. For now that's defined
 as total variance from a sample to its neighbo(u)r in a block of 16 samples.

---
 source/soundux.cpp | 88 +++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 71 insertions(+), 17 deletions(-)

diff --git a/source/soundux.cpp b/source/soundux.cpp
index d8ce223..b8df25a 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -840,6 +840,9 @@ void DecodeBlock (Channel *ch)
 	    filter = *compressed;
 	    if ((ch->last_block = filter & 1))
 			ch->loop = (filter & 2) != 0;
+
+		int16 interim[16];
+		uint8 interim_byte;
 	
 		compressed++;
 		signed short *raw = ch->block = ch->decoded;
@@ -899,29 +902,80 @@ void DecodeBlock (Channel *ch)
 				int16 result = (signed short)(out<<1);
 				if (abs(result) > amplitude)
 					amplitude = abs(result);
+				interim[interim_byte++] = out;
 				prev1=(signed short)prev0;
 				prev0=(signed short)(out<<1);
 			}
 		}
 		ch->previous [0] = prev0;
 		ch->previous [1] = prev1;
-		// Make it a square wave with an amplitude equivalent to that
-		// of the highest amplitude sample of the block.
-		/* for (i = 0; i < 8; i++)
-			ch->decoded[i] = amplitude;
-		for (i = 8; i < 16; i++)
-			ch->decoded[i] = -amplitude; */
-		// Make it a triangle wave with an amplitude equivalent to that
-		// of the highest amplitude sample of the block.
-		ch->decoded[0] =  ch->decoded[8]  = 0;
-		ch->decoded[1] =  ch->decoded[7]  = amplitude / 4;
-		ch->decoded[2] =  ch->decoded[6]  = amplitude / 2;
-		ch->decoded[3] =  ch->decoded[5]  = amplitude * 3 / 4;
-		ch->decoded[4] =  amplitude;
-		ch->decoded[9] =  ch->decoded[15] = -(amplitude / 4);
-		ch->decoded[10] = ch->decoded[14] = -(amplitude / 2);
-		ch->decoded[11] = ch->decoded[13] = -(amplitude * 3 / 4);
-		ch->decoded[12] = -amplitude;
+
+		int32 total_deviation_from_previous = 0;
+		for (i = 1; i < 16; i++)
+			total_deviation_from_previous += abs(interim[i] - interim[i - 1]);
+		if (total_deviation_from_previous >= (int32) amplitude * 4)
+		{
+			/* Looks like noise. Generate noise. */
+			for (i = 0; i < 16; i++)
+			{
+				int feedback = (noise_gen << 13) ^ (noise_gen << 14);
+				noise_gen = (feedback & 0x4000) ^ (noise_gen >> 1);
+				ch->decoded[i] = (noise_gen << 17) >> 17;
+			}
+		}
+		else if (interim[0] < interim[1] && interim[1] < interim[2]
+		 && interim[2] < interim[3]
+		 && interim[4] > interim[5] && interim[5] > interim[6]
+		 && interim[6] > interim[7] && interim[7] > interim[8]
+		 && interim[8] > interim[9] && interim[9] > interim[10]
+		 && interim[10] > interim[11]
+		 && interim[12] < interim[13] && interim[13] < interim[14]
+		 && interim[14] < interim[15])
+		{
+			/* Looks like a sine or triangle wave. Make it a
+			 * triangle wave with an amplitude equivalent to that
+			 * of the highest amplitude sample of the block. */
+			ch->decoded[0] =  ch->decoded[8]  = 0;
+			ch->decoded[1] =  ch->decoded[7]  = amplitude / 4;
+			ch->decoded[2] =  ch->decoded[6]  = amplitude / 2;
+			ch->decoded[3] =  ch->decoded[5]  = amplitude * 3 / 4;
+			ch->decoded[4] =  amplitude;
+			ch->decoded[9] =  ch->decoded[15] = -(amplitude / 4);
+			ch->decoded[10] = ch->decoded[14] = -(amplitude / 2);
+			ch->decoded[11] = ch->decoded[13] = -(amplitude * 3 / 4);
+			ch->decoded[12] = -amplitude;
+		}
+		else if (interim[0] > interim[1] && interim[1] > interim[2]
+		 && interim[2] > interim[3]
+		 && interim[4] < interim[5] && interim[5] < interim[6]
+		 && interim[6] < interim[7] && interim[7] < interim[8]
+		 && interim[8] < interim[9] && interim[9] < interim[10]
+		 && interim[10] < interim[11]
+		 && interim[12] > interim[13] && interim[13] > interim[14]
+		 && interim[14] > interim[15])
+		{
+			/* Inverted triangle wave. */
+			ch->decoded[0] =  ch->decoded[8]  = 0;
+			ch->decoded[1] =  ch->decoded[7]  = -(amplitude / 4);
+			ch->decoded[2] =  ch->decoded[6]  = -(amplitude / 2);
+			ch->decoded[3] =  ch->decoded[5]  = -(amplitude * 3 / 4);
+			ch->decoded[4] = -amplitude;
+			ch->decoded[9] =  ch->decoded[15] = amplitude / 4;
+			ch->decoded[10] = ch->decoded[14] = amplitude / 2;
+			ch->decoded[11] = ch->decoded[13] = amplitude * 3 / 4;
+			ch->decoded[12] = amplitude;
+		}
+		else
+		{
+			// Make it a square wave with an amplitude equivalent to that
+			// of the highest amplitude sample of the block.
+			// But actually put half of the amplitude, because
+			// square waves are just loud.
+			for (i = 0; i < 8; i++)
+				ch->decoded[i] = amplitude / 2;
+			for (i = 8; i < 16; i++)
+				ch->decoded[i] = -amplitude / 2;
+		}
 	}
 	else
 	{
-- 
cgit v1.2.3


From 3834297fae931341c40bb293efb2f10cf7549d26 Mon Sep 17 00:00:00 2001
From: Nebuleon Fumika
Date: Fri, 8 Feb 2013 15:46:33 -0500
Subject: Fix write to uninitialised memory in 8-bit sound.

---
 source/soundux.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/source/soundux.cpp b/source/soundux.cpp
index b8df25a..399b04b 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -842,7 +842,7 @@ void DecodeBlock (Channel *ch)
 			ch->loop = (filter & 2) != 0;
 
 		int16 interim[16];
-		uint8 interim_byte;
+		uint8 interim_byte = 0;
 	
 		compressed++;
 		signed short *raw = ch->block = ch->decoded;
@@ -974,7 +974,7 @@ void DecodeBlock (Channel *ch)
 			for (i = 0; i < 8; i++)
 				ch->decoded[i] = amplitude / 2;
 			for (i = 8; i < 16; i++)
-				ch->decoded[i] = -amplitude / 2;
+				ch->decoded[i] = -(amplitude / 2);
 		}
 	}
 	else
-- 
cgit v1.2.3


From 9ef4103ea59d3048f4a692c038a75dc933ff28ac Mon Sep 17 00:00:00 2001
From: Nebuleon Fumika
Date: Fri, 8 Feb 2013 16:08:48 -0500
Subject: Add two more half-wave types to try to correct the pitch of notes
 that are one octave too high.

---
 source/soundux.cpp | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/source/soundux.cpp b/source/soundux.cpp
index 399b04b..6998166 100644
--- a/source/soundux.cpp
+++ b/source/soundux.cpp
@@ -965,6 +965,48 @@ void DecodeBlock (Channel *ch)
 			ch->decoded[11] = ch->decoded[13] = amplitude * 3 / 4;
 			ch->decoded[12] = amplitude;
 		}
+		else if (interim[0] < interim[1] && interim[1] < interim[2]
+		 && interim[2] < interim[3] && interim[3] < interim[4]
+		 && interim[4] < interim[5] && interim[5] < interim[6]
+		 && interim[6] < interim[7]
+		 && interim[8] > interim[9] && interim[9] > interim[10]
+		 && interim[10] > interim[11] && interim[11] > interim[12]
+		 && interim[12] > interim[13] && interim[13] > interim[14]
+		 && interim[14] > interim[15])
+		{
+			/* Looks like a V wave. Make it a half-triangle wave
+			 * with an amplitude equivalent to that
+			 * of the highest amplitude sample of the block. */
+			ch->decoded[0] =  0;
+			ch->decoded[1] =  ch->decoded[15] = amplitude / 8;
+			ch->decoded[2] =  ch->decoded[14] = amplitude / 4;
+			ch->decoded[3] =  ch->decoded[13] = amplitude * 3 / 8;
+			ch->decoded[4] =  ch->decoded[12] = amplitude / 2;
+			ch->decoded[5] =  ch->decoded[11] = amplitude * 5 / 8;
+			ch->decoded[6] =  ch->decoded[10] = amplitude * 3 / 4;
+			ch->decoded[7] =  ch->decoded[9]  = amplitude * 7 / 8;
+			ch->decoded[8] =  amplitude;
+		}
+		else if (interim[0] > interim[1] && interim[1] > interim[2]
+		 && interim[2] > interim[3] && interim[3] > interim[4]
+		 && interim[4] > interim[5] && interim[5] > interim[6]
+		 && interim[6] > interim[7]
+		 && interim[8] < interim[9] && interim[9] < interim[10]
+		 && interim[10] < interim[11] && interim[11] < interim[12]
+		 && interim[12] < interim[13] && interim[13] < interim[14]
+		 && interim[14] < interim[15])
+		{
+			/* Inverted V wave. */
+			ch->decoded[0] =  0;
+			ch->decoded[1] =  ch->decoded[15] = -(amplitude / 8);
+			ch->decoded[2] =  ch->decoded[14] = -(amplitude / 4);
+			ch->decoded[3] =  ch->decoded[13] = -(amplitude * 3 / 8);
+			ch->decoded[4] =  ch->decoded[12] = -(amplitude / 2);
+			ch->decoded[5] =  ch->decoded[11] = -(amplitude * 5 / 8);
+			ch->decoded[6] =  ch->decoded[10] = -(amplitude * 3 / 4);
+			ch->decoded[7] =  ch->decoded[9]  = -(amplitude * 7 / 8);
+			ch->decoded[8] =  -amplitude;
+		}
 		else
 		{
 			// Make it a square wave with an amplitude equivalent to that
-- 
cgit v1.2.3