Add class CUserInterface

The user interface should be implemented here. As a start it supports
showing the program number and name on the LCD display. The LCD output
is buffered, so that LCD writes from an IRQ handler are possible.

src/Makefile

@@ -5,7 +5,8 @@
 CIRCLE_STDLIB_DIR = ../circle-stdlib
 SYNTH_DEXED_DIR = ../Synth_Dexed/src
 
-OBJS = main.o kernel.o minidexed.o config.o pckeyboard.o sysexfileloader.o perftimer.o \
+OBJS = main.o kernel.o minidexed.o config.o userinterface.o pckeyboard.o \
+       sysexfileloader.o perftimer.o \
        $(SYNTH_DEXED_DIR)/synth_dexed.o
 
 INCLUDE += -I $(SYNTH_DEXED_DIR)

src/minidexed.cpp

@@ -18,19 +18,16 @@ CMiniDexed *CMiniDexed::s_pThis = 0;
 
 bool CMiniDexed::Initialize (void)
 {
-  m_SysExFileLoader.Load ();
-
-  if (!m_Serial.Initialize(m_pConfig->GetMIDIBaudRate ()))
+  if (!m_UI.Initialize ())
   {
     return false;
   }
 
-  if (m_pLCD)
+  m_SysExFileLoader.Load ();
+
+  if (!m_Serial.Initialize(m_pConfig->GetMIDIBaudRate ()))
   {
-    if (!m_pLCD->Initialize ())
-    {
-      return FALSE;
-    }
+    return false;
   }
 
   m_bUseSerial = true;
@@ -50,6 +47,8 @@ void CMiniDexed::Process(boolean bPlugAndPlayUpdated)
 		m_GetChunkTimer.Dump ();
 	}
 
+	m_UI.Process ();
+
 	if (m_pMIDIDevice != 0)
 	{
 		return;
@@ -203,22 +202,15 @@ void CMiniDexed::MIDIPacketHandler (unsigned nCable, u8 *pPacket, unsigned nLeng
 }
 
 void CMiniDexed::ChangeProgram(unsigned program) {
-		if(program > 31) {
-			return;
-		}
-		printf ("Loading voice %u\n", (unsigned) program+1); // MIDI numbering starts with 0, user interface with 1
-		uint8_t Buffer[156];
-		s_pThis->m_SysExFileLoader.GetVoice (program, Buffer);
-		s_pThis->loadVoiceParameters(Buffer);
-		char buf_name[11];
-		memset(buf_name, 0, 11); // Initialize with 0x00 chars
-		s_pThis->setName(buf_name);
-		printf ("%s\n", buf_name);
-		// Print to optional HD44780 display
-		s_pThis->LCDWrite("\x1B[?25l");		// cursor off
-		CString String;
-		String.Format ("\n\r%i\n\r%s", program+1, buf_name); // MIDI numbering starts with 0, user interface with 1
-		s_pThis->LCDWrite ((const char *) String);
+	if(program > 31) {
+		return;
+	}
+
+	uint8_t Buffer[156];
+	m_SysExFileLoader.GetVoice (program, Buffer);
+	loadVoiceParameters (Buffer);
+
+	m_UI.ProgramChanged (program);
 }
 
 void CMiniDexed::USBDeviceRemovedHandler (CDevice *pDevice, void *pContext)
@@ -338,11 +330,3 @@ unsigned CMiniDexedHDMI::GetChunk(u32 *pBuffer, unsigned nChunkSize)
 
   return(nResult);
 };
-
-void CMiniDexed::LCDWrite (const char *pString)
-{
-	if (m_pLCD)
-	{
-		m_pLCD->Write (pString, strlen (pString));
-	}
-}

src/minidexed.h

@@ -19,7 +19,7 @@
 #include "sysexfileloader.h"
 #include "pckeyboard.h"
 #include "perftimer.h"
-#include <display/hd44780device.h>
+#include "userinterface.h"
 
 class CMiniDexed : public CDexedAdapter
 {
@@ -33,28 +33,17 @@ class CMiniDexed : public CDexedAdapter
     m_nSerialState (0),
     m_GetChunkTimer ("GetChunk", 1000000U * pConfig->GetChunkSize ()/2 / pConfig->GetSampleRate ()),
     m_pConfig (pConfig),
-    m_pLCD (0)
+    m_UI (this, pConfig)
     {
       s_pThis = this;
-
-      if (pConfig->GetLCDEnabled ())
-      {
-        m_pLCD = new CHD44780Device (CConfig::LCDColumns, CConfig::LCDRows,
-                                     pConfig->GetLCDPinData4 (), pConfig->GetLCDPinData5 (),
-                                     pConfig->GetLCDPinData6 (), pConfig->GetLCDPinData7 (),
-                                     pConfig->GetLCDPinEnable (), pConfig->GetLCDPinRegisterSelect (),
-                                     pConfig->GetLCDPinReadWrite ());
-      }
     };
 
     virtual bool Initialize (void);
     void Process(boolean bPlugAndPlayUpdated);
-  private:
-    void LCDWrite (const char *pString);
   protected:
     static void MIDIPacketHandler (unsigned nCable, u8 *pPacket, unsigned nLength);
     static void KeyStatusHandlerRaw (unsigned char ucModifiers, const unsigned char RawKeys[6]);
-    static void ChangeProgram(unsigned program);
+    void ChangeProgram(unsigned program);
     static void USBDeviceRemovedHandler (CDevice *pDevice, void *pContext);
     CUSBMIDIDevice     * volatile m_pMIDIDevice;
     CPCKeyboard        m_PCKeyboard;
@@ -66,7 +55,7 @@ class CMiniDexed : public CDexedAdapter
     CPerformanceTimer m_GetChunkTimer;
   private:
     CConfig             *m_pConfig;
-    CHD44780Device	*m_pLCD;
+    CUserInterface	m_UI;
 
     static CMiniDexed *s_pThis;
 };

src/userinterface.cpp

@@ -0,0 +1,107 @@
+//
+// userinterface.cpp
+//
+// MiniDexed - Dexed FM synthesizer for bare metal Raspberry Pi
+// Copyright (C) 2022  The MiniDexed Team
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+#include "userinterface.h"
+#include "minidexed.h"
+#include <circle/logger.h>
+#include <circle/string.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+LOGMODULE ("ui");
+
+CUserInterface::CUserInterface (CMiniDexed *pMiniDexed, CConfig *pConfig)
+:	m_pMiniDexed (pMiniDexed),
+	m_pConfig (pConfig),
+	m_pLCD (0),
+	m_pLCDBuffered (0)
+{
+}
+
+CUserInterface::~CUserInterface (void)
+{
+	delete m_pLCDBuffered;
+	delete m_pLCD;
+}
+
+bool CUserInterface::Initialize (void)
+{
+	assert (m_pConfig);
+
+	if (m_pConfig->GetLCDEnabled ())
+	{
+		m_pLCD = new CHD44780Device (CConfig::LCDColumns, CConfig::LCDRows,
+					     m_pConfig->GetLCDPinData4 (),
+					     m_pConfig->GetLCDPinData5 (),
+					     m_pConfig->GetLCDPinData6 (),
+					     m_pConfig->GetLCDPinData7 (),
+					     m_pConfig->GetLCDPinEnable (),
+					     m_pConfig->GetLCDPinRegisterSelect (),
+					     m_pConfig->GetLCDPinReadWrite ());
+		assert (m_pLCD);
+
+		if (!m_pLCD->Initialize ())
+		{
+			return false;
+		}
+
+		m_pLCDBuffered = new CWriteBufferDevice (m_pLCD);
+		assert (m_pLCDBuffered);
+
+		LCDWrite ("\x1B[?25l");		// cursor off
+
+		LOGDBG ("LCD initialized");
+	}
+
+	return true;
+}
+
+void CUserInterface::Process (void)
+{
+	if (m_pLCDBuffered)
+	{
+		m_pLCDBuffered->Update ();
+	}
+}
+
+void CUserInterface::ProgramChanged (unsigned nProgram)
+{
+	nProgram++;	// MIDI numbering starts with 0, user interface with 1
+
+	// fetch program name from Dexed instance
+	char ProgramName[11];
+	memset (ProgramName, 0, sizeof ProgramName);
+	assert (m_pMiniDexed);
+	m_pMiniDexed->setName (ProgramName);
+
+	printf ("Loading voice %u: \"%s\"\n", nProgram, ProgramName);
+
+	CString String;
+	String.Format ("\n\r%u\n\r%s", nProgram, ProgramName);
+	LCDWrite (String);
+}
+
+void CUserInterface::LCDWrite (const char *pString)
+{
+	if (m_pLCDBuffered)
+	{
+		m_pLCDBuffered->Write (pString, strlen (pString));
+	}
+}

src/userinterface.h

@@ -0,0 +1,52 @@
+//
+// userinterface.h
+//
+// MiniDexed - Dexed FM synthesizer for bare metal Raspberry Pi
+// Copyright (C) 2022  The MiniDexed Team
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+#ifndef _userinterface_h
+#define _userinterface_h
+
+#include "config.h"
+#include <display/hd44780device.h>
+#include <circle/writebuffer.h>
+
+class CMiniDexed;
+
+class CUserInterface
+{
+public:
+	CUserInterface (CMiniDexed *pMiniDexed, CConfig *pConfig);
+	~CUserInterface (void);
+
+	bool Initialize (void);
+
+	void Process (void);
+
+	void ProgramChanged (unsigned nProgram);	// 0 .. 127
+
+private:
+	void LCDWrite (const char *pString);		// Print to optional HD44780 display
+
+private:
+	CMiniDexed *m_pMiniDexed;
+	CConfig *m_pConfig;
+
+	CHD44780Device *m_pLCD;
+	CWriteBufferDevice *m_pLCDBuffered;
+};
+
+#endif