initial commit

oscar64/include/audio/sidfx.c

@@ -0,0 +1,201 @@
+#include "sidfx.h"
+
+enum SIDFXState
+{
+	SIDFX_IDLE,
+	SIDFX_RESET_0,
+	SIDFX_RESET_1,
+	SIDFX_READY,
+	SIDFX_PLAY,
+	SIDFX_WAIT
+};
+
+__striped static struct SIDFXChannel
+{
+	const SIDFX	* volatile 		com;
+	byte						delay, priority;
+	volatile byte				cnt;
+	volatile SIDFXState			state;
+	unsigned					freq, pwm;
+
+}	channels[3];
+
+void sidfx_init(void)
+{
+	for(char i=0; i<3; i++)
+	{
+		channels[i].com = nullptr;
+		channels[i].state = SIDFX_IDLE;
+		channels[i].priority = 0;
+		channels[i].delay = 1;
+	}
+}
+
+bool sidfx_idle(byte chn)
+{
+	return channels[chn].state == SIDFX_IDLE;
+}
+
+char sidfx_cnt(byte chn)
+{
+	return channels[chn].cnt;	
+}
+
+void sidfx_play(byte chn, const SIDFX * fx, byte cnt)
+{
+	SIDFXState		ns = channels[chn].state;
+
+	if (ns == SIDFX_IDLE)
+		ns = SIDFX_READY;
+	else if (channels[chn].priority <= fx->priority)
+		ns = SIDFX_RESET_1;
+	else
+		return;
+
+	channels[chn].state = SIDFX_IDLE;
+	channels[chn].delay = 1;
+
+	channels[chn].com = fx;
+	channels[chn].cnt = cnt - 1;
+	channels[chn].priority = fx->priority;
+
+	channels[chn].state = ns;
+}
+
+void sidfx_stop(byte chn)
+{
+	channels[chn].com = nullptr;
+	if (channels[chn].state != SIDFX_IDLE)
+	{
+		channels[chn].state = SIDFX_RESET_0;
+		channels[chn].delay = 1;
+	}
+}
+
+inline void sidfx_loop_ch(byte ch)
+{
+	if (channels[ch].state)
+	{
+		const SIDFX	*	com = channels[ch].com;
+
+		channels[ch].delay--;
+		if (channels[ch].delay)
+		{
+			if (com->dfreq)
+			{
+				channels[ch].freq += com->dfreq;
+				sid.voices[ch].freq = channels[ch].freq;
+			}
+			if (com->dpwm)
+			{
+				channels[ch].pwm += com->dpwm;
+				sid.voices[ch].pwm = channels[ch].pwm;
+			}
+		}
+
+		while (!channels[ch].delay)
+		{
+			switch (channels[ch].state)
+			{
+			case SIDFX_IDLE:
+				channels[ch].delay = 1;
+				break;
+			case SIDFX_RESET_0:
+				sid.voices[ch].ctrl = 0;
+				sid.voices[ch].attdec = 0;
+				sid.voices[ch].susrel = 0;
+				if (com)
+					channels[ch].state = SIDFX_READY;
+				else
+					channels[ch].state = SIDFX_IDLE;
+				channels[ch].delay = 1;
+				break;
+			case SIDFX_RESET_1:
+				sid.voices[ch].ctrl = SID_CTRL_TEST;
+				sid.voices[ch].ctrl = 0;
+				sid.voices[ch].attdec = 0;
+				sid.voices[ch].susrel = 0;
+				channels[ch].state = SIDFX_READY;
+				break;
+			case SIDFX_READY:
+				channels[ch].freq = com->freq;
+				channels[ch].pwm = com->pwm;
+
+				sid.voices[ch].freq = com->freq;
+				sid.voices[ch].pwm = com->pwm;
+				sid.voices[ch].attdec = com->attdec;
+				sid.voices[ch].susrel = com->susrel;
+				sid.voices[ch].ctrl = com->ctrl;
+
+				if (com->ctrl & SID_CTRL_GATE)
+				{
+					channels[ch].delay = com->time1;
+					channels[ch].state = SIDFX_PLAY;
+				}
+				else
+				{
+					channels[ch].delay = com->time0;
+					channels[ch].state = SIDFX_PLAY;
+				}
+				break;
+			case SIDFX_PLAY:
+				if (com->time0)
+				{
+					sid.voices[ch].ctrl = com->ctrl & ~SID_CTRL_GATE;
+					channels[ch].delay = com->time0 - 1;
+					channels[ch].state = SIDFX_WAIT;
+				}
+				else if (channels[ch].cnt)
+				{
+					char sr = com->susrel & 0xf0;
+					com++;
+					char ctrl = com->ctrl;
+					if ((com->attdec & 0xef) == 0 && (ctrl & SID_CTRL_GATE) && (com->susrel & 0xf0) > sr)
+					{
+						sid.voices[ch].ctrl = ctrl & ~SID_CTRL_GATE;
+						sid.voices[ch].ctrl = ctrl |  SID_CTRL_GATE;
+					}
+					channels[ch].cnt--;
+					channels[ch].com = com;
+					channels[ch].priority = com->priority;
+					channels[ch].state = SIDFX_READY;
+				}
+				else
+				{
+					com = nullptr;
+					channels[ch].state = SIDFX_RESET_0;					
+				}
+				break;
+			case SIDFX_WAIT:
+				if (channels[ch].cnt)
+				{
+					com++;
+					channels[ch].cnt--;
+					channels[ch].com = com;
+					channels[ch].priority = com->priority;
+					if (com->ctrl & SID_CTRL_GATE)
+						channels[ch].state = SIDFX_RESET_0;
+					else
+						channels[ch].state = SIDFX_READY;
+				}
+				else
+				{
+					com = nullptr;
+					channels[ch].state = SIDFX_RESET_0;					
+				}
+				break;
+			}
+		}
+	}
+}
+
+void sidfx_loop_2(void)
+{
+	sidfx_loop_ch(2);	
+}
+
+void sidfx_loop(void)
+{
+	for(byte ch=0; ch<3; ch++)
+		sidfx_loop_ch(ch);
+}	

oscar64/include/audio/sidfx.h

@@ -0,0 +1,31 @@
+#ifndef SIDFX_H
+#define SIDFX_H
+
+#include <c64/sid.h>
+
+struct SIDFX
+{
+	unsigned	freq, pwm;
+	byte		ctrl, attdec, susrel;
+	int			dfreq, dpwm;
+	byte		time1, time0;
+	byte		priority;
+};
+
+void sidfx_init(void);
+
+inline bool sidfx_idle(byte chn);
+
+inline void sidfx_play(byte chn, const SIDFX * fx, byte cnt);
+
+void sidfx_stop(byte chn);
+
+char sidfx_cnt(byte chn);
+
+void sidfx_loop(void);
+
+void sidfx_loop_2(void);
+
+#pragma compile("sidfx.c")
+
+#endif