Fix for Issue #458 to not show blank banks in the menus. Also handles MIDI bank select messages and won't change banks if the final selected bank isn't loaded.

src/minidexed.cpp

@@ -61,6 +61,7 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 	for (unsigned i = 0; i < CConfig::ToneGenerators; i++)
 	{
 		m_nVoiceBankID[i] = 0;
+		m_nVoiceBankIDMSB[i] = 0;
 		m_nProgram[i] = 0;
 		m_nVolume[i] = 100;
 		m_nPan[i] = 64;
@@ -371,10 +372,9 @@ void CMiniDexed::BankSelect (unsigned nBank, unsigned nTG)
 
 	assert (nTG < CConfig::ToneGenerators);
 	
-	unsigned nHighestBank = GetSysExFileLoader ()->GetNumHighestBank();
-	
-	if (nBank <= nHighestBank)
+	if (GetSysExFileLoader ()->IsValidBank(nBank))
 	{
+		// Only change if we have the bank loaded
 		m_nVoiceBankID[nTG] = nBank;
 
 		m_UI.ParameterChanged ();
@@ -386,11 +386,14 @@ void CMiniDexed::BankSelectMSB (unsigned nBankMSB, unsigned nTG)
 	nBankMSB=constrain((int)nBankMSB,0,127);
 
 	assert (nTG < CConfig::ToneGenerators);
-	unsigned nBank = m_nVoiceBankID[nTG];
-	unsigned nBankLSB = nBank & 0x7F;
-	nBank = (nBankMSB << 7) + nBankLSB;
-
-	BankSelect(nBank, nTG);
+	// MIDI Spec 1.0 "BANK SELECT" states:
+	//   "The transmitter must transmit the MSB and LSB as a pair,
+	//   and the Program Change must be sent immediately after
+	//   the Bank Select pair."
+	//
+	// So it isn't possible to validate the selected bank ID until
+	// we receive both MSB and LSB so just store the MSB for now.
+	m_nVoiceBankIDMSB[nTG] = nBankMSB;
 }
 
 void CMiniDexed::BankSelectLSB (unsigned nBankLSB, unsigned nTG)
@@ -399,9 +402,10 @@ void CMiniDexed::BankSelectLSB (unsigned nBankLSB, unsigned nTG)
 
 	assert (nTG < CConfig::ToneGenerators);
 	unsigned nBank = m_nVoiceBankID[nTG];
-	unsigned nBankMSB = nBank >> 7;
+	unsigned nBankMSB = m_nVoiceBankIDMSB[nTG];
 	nBank = (nBankMSB << 7) + nBankLSB;
 
+	// Now should have both MSB and LSB so enable the BankSelect
 	BankSelect(nBank, nTG);
 }
 

src/minidexed.h

@@ -231,6 +231,7 @@ private:
 	CDexedAdapter *m_pTG[CConfig::ToneGenerators];
 
 	unsigned m_nVoiceBankID[CConfig::ToneGenerators];
+	unsigned m_nVoiceBankIDMSB[CConfig::ToneGenerators];
 	unsigned m_nProgram[CConfig::ToneGenerators];
 	unsigned m_nVolume[CConfig::ToneGenerators];
 	unsigned m_nPan[CConfig::ToneGenerators];

src/sysexfileloader.cpp

@@ -192,6 +192,68 @@ std::string CSysExFileLoader::GetBankName (unsigned nBankID)
 	return "NO NAME";
 }
 
+unsigned CSysExFileLoader::GetNextBankUp (unsigned nBankID)
+{
+	// Find the next loaded bank "up" from the provided bank ID
+	for (unsigned id=nBankID+1; id <= m_nNumHighestBank; id++)
+	{
+		if (IsValidBank(id))
+		{
+			return id;
+		}
+	}
+	
+	// Handle wrap-around
+	for (unsigned id=0; id<nBankID; id++)
+	{
+		if (IsValidBank(id))
+		{
+			return id;
+		}
+	}
+	
+	// If we get here there are no other banks!
+	return nBankID;
+}
+
+unsigned CSysExFileLoader::GetNextBankDown (unsigned nBankID)
+{
+	// Find the next loaded bank "down" from the provided bank ID
+	for (int id=((int)nBankID)-1; id >= 0; id--)
+	{
+		if (IsValidBank((unsigned)id))
+		{
+			return id;
+		}
+	}
+
+	// Handle wrap-around
+	for (unsigned id=m_nNumHighestBank; id>nBankID; id--)
+	{
+		if (IsValidBank(id))
+		{
+			return id;
+		}
+	}
+	
+	// If we get here there are no other banks!
+	return nBankID;
+}
+
+bool CSysExFileLoader::IsValidBank (unsigned nBankID)
+{
+	// Use a valid "status start/end" as an indicator of a loaded bank
+	if ((m_pVoiceBank[nBankID]->StatusStart == 0xF0) &&
+		(m_pVoiceBank[nBankID]->StatusEnd == 0xF7))
+	{
+		return true;
+	}
+	else
+	{
+		return false;
+	}
+}
+
 unsigned CSysExFileLoader::GetNumHighestBank (void)
 {
 	return m_nNumHighestBank;

src/sysexfileloader.h

@@ -58,6 +58,9 @@ public:
 
 	std::string GetBankName (unsigned nBankID);	// 0 .. MaxVoiceBankID
 	unsigned GetNumHighestBank (); // 0 .. MaxVoiceBankID
+	bool     IsValidBank (unsigned nBankID);
+	unsigned GetNextBankUp (unsigned nBankID);
+	unsigned GetNextBankDown (unsigned nBankID);
 
 	void GetVoice (unsigned nBankID,		// 0 .. MaxVoiceBankID
 		       unsigned nVoiceID,		// 0 .. 31

src/uimenu.cpp

@@ -486,7 +486,6 @@ void CUIMenu::EditGlobalParameter (CUIMenu *pUIMenu, TMenuEvent Event)
 void CUIMenu::EditVoiceBankNumber (CUIMenu *pUIMenu, TMenuEvent Event)
 {
 	unsigned nTG = pUIMenu->m_nMenuStackParameter[pUIMenu->m_nCurrentMenuDepth-1];
-	int nHighestBank = pUIMenu->m_pMiniDexed->GetSysExFileLoader ()->GetNumHighestBank();
 
 	int nValue = pUIMenu->m_pMiniDexed->GetTGParameter (CMiniDexed::TGParameterVoiceBank, nTG);
 
@@ -496,19 +495,13 @@ void CUIMenu::EditVoiceBankNumber (CUIMenu *pUIMenu, TMenuEvent Event)
 		break;
 
 	case MenuEventStepDown:
-		if (--nValue < 0)
-		{
-			nValue = 0;
-		}
+		nValue = pUIMenu->m_pMiniDexed->GetSysExFileLoader ()->GetNextBankDown(nValue);
 		pUIMenu->m_pMiniDexed->SetTGParameter (
 			CMiniDexed::TGParameterVoiceBank, nValue, nTG);
 		break;
 
 	case MenuEventStepUp:
-		if (++nValue > (int) nHighestBank)
-		{
-			nValue = nHighestBank;
-		}
+		nValue = pUIMenu->m_pMiniDexed->GetSysExFileLoader ()->GetNextBankUp(nValue);
 		pUIMenu->m_pMiniDexed->SetTGParameter (
 			CMiniDexed::TGParameterVoiceBank, nValue, nTG);
 		break;