Support multiple Dexed instances (#50)

* dexedadapter: Protect setSustain() with spin-lock too

* Initial support for multiple Dexed instances

* Currently 2 similar instances, which work with the same parameters
* Only 1 instance with max. 8 notes polyphony on RPi 1
* Chunk size needs to be increased on RPi 1

* Support 8 Dexed instances (TGs) with multi-core

* Core 1 kicks core 2 and 3 and processes two TGs then
* Cores 2 and 3 wait for a kick and process three TGs each then
* When all cores are ready, the output will be summed up
* All 8 TGs generate the same sound at the moment
* The maximum chunk size is limited to 4096 now

* Maintain voice bank number per TG

* Support TG select in UI

* Active TG number is shown on LCD display
* Next TG is selected by double click
* MIDI receive and PC keyboard are still in omni mode

* pckeyboard: Fake MIDI events

* on MIDI cable 0, channel 0
* instead of calling key[down|up]()
* derive from class CMIDIDevice

* ui: Precede screen messages with TG number

* Configure MIDI mapping from UI

* ui: New menu item "MIDI" for configures assigned MIDI channel
* ui: Holding switch for at least one second returns to menu home
* ui: Do not show TG instance, if there is only one
* By default TG1 is in omni mode, all other TGs are not assigned
* config: Default chunk size is 1024 without multi-core

Author: rsta2

src/config.cpp

@@ -38,7 +38,11 @@ void CConfig::Load (void)
 	m_SoundDevice = m_Properties.GetString ("SoundDevice", "pwm");
 
 	m_nSampleRate = m_Properties.GetNumber ("SampleRate", 48000);
+#ifdef ARM_ALLOW_MULTI_CORE
 	m_nChunkSize = m_Properties.GetNumber ("ChunkSize", m_SoundDevice == "hdmi" ? 384*6 : 256);
+#else
+	m_nChunkSize = m_Properties.GetNumber ("ChunkSize", m_SoundDevice == "hdmi" ? 384*6 : 1024);
+#endif
 	m_nDACI2CAddress = m_Properties.GetNumber ("DACI2CAddress", 0);
 
 	m_nMIDIBaudRate = m_Properties.GetNumber ("MIDIBaudRate", 31250);

src/config.h

@@ -25,12 +25,27 @@
 
 #include <fatfs/ff.h>
 #include <Properties/propertiesfatfsfile.h>
+#include <circle/sysconfig.h>
 #include <string>
 
 class CConfig		// Configuration for MiniDexed
 {
 public:
-	static const unsigned MaxNotes = 16;		// polyphony
+#ifndef ARM_ALLOW_MULTI_CORE
+	static const unsigned ToneGenerators = 1;
+#else
+	static const unsigned TGsCore1 = 2;		// process 2 TGs on core 1
+	static const unsigned TGsCore23 = 3;		// process 3 TGs on core 2 and 3 each
+	static const unsigned ToneGenerators = TGsCore1 + 2*TGsCore23;
+#endif
+
+#if RASPPI == 1
+	static const unsigned MaxNotes = 8;		// polyphony
+#else
+	static const unsigned MaxNotes = 16;
+#endif
+
+	static const unsigned MaxChunkSize = 4096;
 
 #if RASPPI <= 3
 	static const unsigned MaxUSBMIDIDevices = 2;

src/dexedadapter.h

@@ -70,6 +70,13 @@ class CDexedAdapter : public Dexed
 		m_SpinLock.Release ();
 	}
 
+	void setSustain (bool sustain)
+	{
+		m_SpinLock.Acquire ();
+		Dexed::setSustain (sustain);
+		m_SpinLock.Release ();
+	}
+
 private:
 	CSpinLock m_SpinLock;
 };

src/mididevice.cpp

@@ -45,13 +45,29 @@ CMIDIDevice::CMIDIDevice (CMiniDexed *pSynthesizer, CConfig *pConfig)
 :	m_pSynthesizer (pSynthesizer),
 	m_pConfig (pConfig)
 {
+	for (unsigned nTG = 0; nTG < CConfig::ToneGenerators; nTG++)
+	{
+		m_ChannelMap[nTG] = Disabled;
+	}
 }
 
 CMIDIDevice::~CMIDIDevice (void)
 {
 	m_pSynthesizer = 0;
 }
 
+void CMIDIDevice::SetChannel (u8 ucChannel, unsigned nTG)
+{
+	assert (nTG < CConfig::ToneGenerators);
+	m_ChannelMap[nTG] = ucChannel;
+}
+
+u8 CMIDIDevice::GetChannel (unsigned nTG) const
+{
+	assert (nTG < CConfig::ToneGenerators);
+	return m_ChannelMap[nTG];
+}
+
 void CMIDIDevice::MIDIMessageHandler (const u8 *pMessage, size_t nLength, unsigned nCable)
 {
 	assert (m_pSynthesizer != 0);
@@ -67,17 +83,17 @@ void CMIDIDevice::MIDIMessageHandler (const u8 *pMessage, size_t nLength, unsign
 			if (   pMessage[0] != MIDI_TIMING_CLOCK
 			    && pMessage[0] != MIDI_ACTIVE_SENSING)
 			{
-				printf ("MIDI %u: %02X\n", nCable, (unsigned) pMessage[0]);
+				printf ("MIDI%u: %02X\n", nCable, (unsigned) pMessage[0]);
 			}
 			break;
 
 		case 2:
-			printf ("MIDI %u: %02X %02X\n", nCable,
+			printf ("MIDI%u: %02X %02X\n", nCable,
 				(unsigned) pMessage[0], (unsigned) pMessage[1]);
 			break;
 
 		case 3:
-			printf ("MIDI %u: %02X %02X %02X\n", nCable,
+			printf ("MIDI%u: %02X %02X %02X\n", nCable,
 				(unsigned) pMessage[0], (unsigned) pMessage[1],
 				(unsigned) pMessage[2]);
 			break;
@@ -89,87 +105,93 @@ void CMIDIDevice::MIDIMessageHandler (const u8 *pMessage, size_t nLength, unsign
 		return;
 	}
 
-	u8 ucStatus    = pMessage[0];
-	// TODO: u8 ucChannel   = ucStatus & 0x0F;
-	u8 ucType      = ucStatus >> 4;
-	u8 ucKeyNumber = pMessage[1];
-	u8 ucVelocity  = pMessage[2];
+	u8 ucStatus  = pMessage[0];
+	u8 ucChannel = ucStatus & 0x0F;
+	u8 ucType    = ucStatus >> 4;
 
-	switch (ucType)
+	for (unsigned nTG = 0; nTG < CConfig::ToneGenerators; nTG++)
 	{
-	case MIDI_NOTE_ON:
-		if (nLength < 3)
+		if (   m_ChannelMap[nTG] == ucChannel
+		    || m_ChannelMap[nTG] == OmniMode)
 		{
-			break;
-		}
-
-		if (ucVelocity > 0)
-		{
-			if (ucVelocity <= 127)
+			switch (ucType)
 			{
-				m_pSynthesizer->keydown (ucKeyNumber, ucVelocity);
+			case MIDI_NOTE_ON:
+				if (nLength < 3)
+				{
+					break;
+				}
+
+				if (pMessage[2] > 0)
+				{
+					if (pMessage[2] <= 127)
+					{
+						m_pSynthesizer->keydown (pMessage[1],
+									 pMessage[2], nTG);
+					}
+				}
+				else
+				{
+					m_pSynthesizer->keyup (pMessage[1], nTG);
+				}
+				break;
+
+			case MIDI_NOTE_OFF:
+				if (nLength < 3)
+				{
+					break;
+				}
+
+				m_pSynthesizer->keyup (pMessage[1], nTG);
+				break;
+
+			case MIDI_CONTROL_CHANGE:
+				if (nLength < 3)
+				{
+					break;
+				}
+
+				switch (pMessage[1])
+				{
+				case MIDI_CC_MODULATION:
+					m_pSynthesizer->setModWheel (pMessage[2], nTG);
+					m_pSynthesizer->ControllersRefresh (nTG);
+					break;
+
+				case MIDI_CC_VOLUME:
+					m_pSynthesizer->SetVolume (pMessage[2], nTG);
+					break;
+
+				case MIDI_CC_BANK_SELECT_LSB:
+					m_pSynthesizer->BankSelectLSB (pMessage[2], nTG);
+					break;
+
+				case MIDI_CC_BANK_SUSTAIN:
+					m_pSynthesizer->setSustain (pMessage[2] >= 64, nTG);
+					break;
+				}
+				break;
+
+			case MIDI_PROGRAM_CHANGE:
+				m_pSynthesizer->ProgramChange (pMessage[1], nTG);
+				break;
+
+			case MIDI_PITCH_BEND: {
+				if (nLength < 3)
+				{
+					break;
+				}
+
+				s16 nValue = pMessage[1];
+				nValue |= (s16) pMessage[2] << 7;
+				nValue -= 0x2000;
+
+				m_pSynthesizer->setPitchbend (nValue, nTG);
+				} break;
+
+			default:
+				break;
 			}
 		}
-		else
-		{
-			m_pSynthesizer->keyup (ucKeyNumber);
-		}
-		break;
-
-	case MIDI_NOTE_OFF:
-		if (nLength < 3)
-		{
-			break;
-		}
-
-		m_pSynthesizer->keyup (ucKeyNumber);
-		break;
-
-	case MIDI_CONTROL_CHANGE:
-		if (nLength < 3)
-		{
-			break;
-		}
-
-		switch (pMessage[1])
-		{
-		case MIDI_CC_MODULATION:
-			m_pSynthesizer->setModWheel (pMessage[2]);
-			m_pSynthesizer->ControllersRefresh ();
-			break;
-
-		case MIDI_CC_VOLUME:
-			m_pSynthesizer->SetVolume (pMessage[2]);
-			break;
-
-		case MIDI_CC_BANK_SELECT_LSB:
-			m_pSynthesizer->BankSelectLSB (pMessage[2]);
-			break;
-
-		case MIDI_CC_BANK_SUSTAIN:
-			m_pSynthesizer->setSustain (pMessage[2] >= 64);
-			break;
-		}
-		break;
-
-	case MIDI_PROGRAM_CHANGE:
-		m_pSynthesizer->ProgramChange (pMessage[1]);
-		break;
-
-	case MIDI_PITCH_BEND: {
-		if (nLength < 3)
-		{
-			break;
-		}
-
-		s16 nValue = pMessage[1];
-		nValue |= (s16) pMessage[2] << 7;
-		nValue -= 0x2000;
-
-		m_pSynthesizer->setPitchbend (nValue);
-		} break;
-
-	default:
-		break;
 	}
 }

src/mididevice.h

@@ -30,16 +30,30 @@ class CMiniDexed;
 
 class CMIDIDevice
 {
+public:
+	enum TChannel
+	{
+		Channels = 16,
+		OmniMode = Channels,
+		Disabled,
+		ChannelUnknown
+	};
+
 public:
 	CMIDIDevice (CMiniDexed *pSynthesizer, CConfig *pConfig);
 	~CMIDIDevice (void);
 
+	void SetChannel (u8 ucChannel, unsigned nTG);
+	u8 GetChannel (unsigned nTG) const;
+
 protected:
 	void MIDIMessageHandler (const u8 *pMessage, size_t nLength, unsigned nCable = 0);
 
 private:
 	CMiniDexed *m_pSynthesizer;
 	CConfig *m_pConfig;
+
+	u8 m_ChannelMap[CConfig::ToneGenerators];
 };
 
 #endif