o Turn BASE_FREQ constant into variable. MT-32 has to be run in lesser time slices.

o Attempt to fix mi2, but that cure for symptom, not the cause. Under dosbox header is always valid, but here we get 0x41001612 instead of 0x41101612.

svn-id: r15669

3 files changed, 14 insertions, 10 deletions

diff --git a/backends/midi/emumidi.h b/backends/midi/emumidi.h
index a7b3821e82..cdff7051d1 100644
--- a/backends/midi/emumidi.h
+++ b/backends/midi/emumidi.h
@@ -23,7 +23,6 @@
 #include "sound/mididrv.h"
 #include "sound/mixer.h"
 
-#define BASE_FREQ 250
 #define FIXP_SHIFT 16
 
 class MidiDriver_Emulated : public AudioStream, public MidiDriver {
@@ -42,6 +41,8 @@ protected:
 	virtual void generate_samples(int16 *buf, int len) = 0;
 	virtual void on_timer() {}
 
+	int _baseFreq;
+
 public:
 	MidiDriver_Emulated(SoundMixer *mixer) : _mixer(mixer) {
 		_isOpen = false;
@@ -51,18 +52,20 @@ public:
 	
 		_next_tick = 0;
 		_samples_per_tick = 0;
+
+		_baseFreq = 250;
 	}
 
 	int open() {
 		_isOpen = true;
 
-		int d = getRate() / BASE_FREQ;
-		int r = getRate() % BASE_FREQ;
+		int d = getRate() / _baseFreq;
+		int r = getRate() % _baseFreq;
 
 		// This is equivalent to (getRate() << FIXP_SHIFT) / BASE_FREQ
 		// but less prone to arithmetic overflow.
 
-		_samples_per_tick = (d << FIXP_SHIFT) + (r << FIXP_SHIFT) / BASE_FREQ;
+		_samples_per_tick = (d << FIXP_SHIFT) + (r << FIXP_SHIFT) / _baseFreq;
 		return 0;
 	}
 
@@ -71,7 +74,7 @@ public:
 		_timer_param = timer_param;
 	}
 
-	uint32 getBaseTempo() { return 1000000 / BASE_FREQ; }
+	uint32 getBaseTempo() { return 1000000 / _baseFreq; }
 
 
 	// AudioStream API
diff --git a/backends/midi/mt32/mt32.cpp b/backends/midi/mt32/mt32.cpp
index c8037e8ca5..d719dafc4e 100644
--- a/backends/midi/mt32/mt32.cpp
+++ b/backends/midi/mt32/mt32.cpp
@@ -72,6 +72,8 @@ MidiDriver_MT32::MidiDriver_MT32(SoundMixer *mixer, const char *path)
 	_synth = new CSynthMT32();
 	rom_path = path;
 	File::addDefaultDirectory(path);
+
+	_baseFreq = 100;
 }
 
 MidiDriver_MT32::~MidiDriver_MT32() {
@@ -83,7 +85,7 @@ int MidiDriver_MT32::open() {
 
 	if (_isOpen)
 		return MERR_ALREADY_OPEN;
-	
+
 	MidiDriver_Emulated::open();
 	
 	prop.SampleRate = getRate(); // 32000;
diff --git a/backends/midi/mt32/synth.cpp b/backends/midi/mt32/synth.cpp
index 0af4832a69..d9272985ee 100644
--- a/backends/midi/mt32/synth.cpp
+++ b/backends/midi/mt32/synth.cpp
@@ -4075,16 +4075,15 @@ void CSynthMT32::PlaySysex(uint8 * sysex,uint32 len) {
 	//int dummy = 0;                                                                  
 	int32 lens = len;                                                              
 
-
 	// For some reason commands in IMuseInternal::initMT32 do not have prefix byte
-	if(READ_LE_UINT32(header) != 0x12161041) {
-		if(READ_LE_UINT32(sysex) == 0x12161041) {
+	if(READ_BE_UINT32(header) != 0x41101612) {
+		if((READ_LE_UINT32(sysex) == 0x41101612) || (READ_BE_UINT32(sysex) == 0x41001612)) {
 			header = (uint32 *)sysex;
 			sysex--; // We don't access sysex[0], so it's safe
 		}
 	}
 
-	if(READ_LE_UINT32(header) == 0x12161041) {
+	if((READ_BE_UINT32(header) == 0x41101612) || (READ_BE_UINT32(header) == 0x41001612)) {
 		addr = (sysex[5] << 16) | (sysex[6] << 8) | (sysex[7]);
 		//LOG_MSG("Sysex addr: %x", addr);
 		if (addr<0x30000) {