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AUDIO: Add AdLib MS driver callback frequency

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This change allows a consumer to specify the desired timer callback frequency
for the AdLib multisource MIDI driver.
This commit is contained in:
Coen Rampen 2022-05-09 15:27:36 +02:00
parent 5e95bdcbda
commit b2cf9a580b
2 changed files with 11 additions and 6 deletions
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11
audio/adlib_ms.cpp
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@ -394,7 +394,7 @@ bool MidiDriver_ADLIB_Multisource::detectOplType(OPL::Config::OplType oplType) {
return OPL::Config::detect(oplType) >= 0;
}
MidiDriver_ADLIB_Multisource::MidiDriver_ADLIB_Multisource(OPL::Config::OplType oplType) :
MidiDriver_ADLIB_Multisource::MidiDriver_ADLIB_Multisource(OPL::Config::OplType oplType, int timerFrequency) :
_oplType(oplType),
_opl(nullptr),
_isOpen(false),
@ -413,9 +413,11 @@ MidiDriver_ADLIB_Multisource::MidiDriver_ADLIB_Multisource(OPL::Config::OplType
_melodicChannels(nullptr),
_numMelodicChannels(0),
_noteCounter(1),
_oplFrequencyConversionFactor(pow(2, 20) / 49716.0f) {
_oplFrequencyConversionFactor(pow(2, 20) / 49716.0f),
_timerFrequency(timerFrequency) {
memset(_channelAllocations, 0xFF, sizeof(_channelAllocations));
Common::fill(_shadowRegisters, _shadowRegisters + sizeof(_shadowRegisters), 0);
_timerRate = 1000000 / _timerFrequency;
}
MidiDriver_ADLIB_Multisource::~MidiDriver_ADLIB_Multisource() {
@ -463,10 +465,9 @@ int MidiDriver_ADLIB_Multisource::open() {
// Set default OPL register values.
initOpl();
_timerRate = getBaseTempo();
// Start the emulator / hardware interface. This will also start the timer
// callbacks.
_opl->start(new Common::Functor0Mem<void, MidiDriver_ADLIB_Multisource>(this, &MidiDriver_ADLIB_Multisource::onTimer));
_opl->start(new Common::Functor0Mem<void, MidiDriver_ADLIB_Multisource>(this, &MidiDriver_ADLIB_Multisource::onTimer), _timerFrequency);
return 0;
}
@ -533,7 +534,7 @@ uint32 MidiDriver_ADLIB_Multisource::property(int prop, uint32 param) {
}
uint32 MidiDriver_ADLIB_Multisource::getBaseTempo() {
return 1000000 / OPL::OPL::kDefaultCallbackFrequency;
return _timerRate;
}
MidiChannel *MidiDriver_ADLIB_Multisource::allocateChannel() {

6
audio/adlib_ms.h
View file

@ -589,8 +589,10 @@ public:
* of OPL chip.
*
* @param oplType The type of OPL chip that should be used.
* @param timerFrequency The number of timer callbacks per second that
* should be generated.
*/
MidiDriver_ADLIB_Multisource(OPL::Config::OplType oplType);
MidiDriver_ADLIB_Multisource(OPL::Config::OplType oplType, int timerFrequency = OPL::OPL::kDefaultCallbackFrequency);
~MidiDriver_ADLIB_Multisource();
/**
@ -1118,6 +1120,8 @@ protected:
// True if the driver has been successfully opened.
bool _isOpen;
// The number of timer callbacks per second.
int _timerFrequency;
// Controls the behavior for calculating note frequency and volume.
AccuracyMode _accuracyMode;
// Controls the OPL channel allocation behavior.