From 78f8fce7f286fd0c71774e2567404ed51f24fef3 Mon Sep 17 00:00:00 2001 From: Vito Caputo Date: Fri, 26 May 2017 21:51:04 -0700 Subject: *: initial commit of stripped schism stuff Forking schism tracker's IT playback stuff into a little playback library for embedding in demos. --- src/include/snd_fm.h | 201 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 201 insertions(+) create mode 100644 src/include/snd_fm.h (limited to 'src/include/snd_fm.h') diff --git a/src/include/snd_fm.h b/src/include/snd_fm.h new file mode 100644 index 0000000..c83b32d --- /dev/null +++ b/src/include/snd_fm.h @@ -0,0 +1,201 @@ +#ifndef _BqtModplugSndFm +#define _BqtModplugSndFm + +void Fmdrv_Init(int mixfreq); +void Fmdrv_MixTo(int* buf, int count); + +void OPL_NoteOff(int c); +void OPL_HertzTouch(int c, int Hertz, int keyoff); // also for pitch bending +void OPL_Touch(int c, const unsigned char *D, unsigned Vol); +void OPL_Pan(int c, signed char val); +void OPL_Patch(int c, const unsigned char *D); +void OPL_Reset(void); +int OPL_Detect(void); +void OPL_Close(void); + +/*************/ + +/* 7.6.1999 01:51 / Bisqwit: + * The rest of this file is clipped from OSS/Free for Linux + */ + +/* + * The OPL-3 mode is switched on by writing 0x01, to the offset 5 + * of the right side. + * + * Another special register at the right side is at offset 4. It contains + * a bit mask defining which voices are used as 4 OP voices. + * + * The percussive mode is implemented in the left side only. + * + * With the above exceptions the both sides can be operated independently. + * + * A 4 OP voice can be created by setting the corresponding + * bit at offset 4 of the right side. + * + * For example setting the rightmost bit (0x01) changes the + * first voice on the right side to the 4 OP mode. The fourth + * voice is made inaccessible. + * + * If a voice is set to the 2 OP mode, it works like 2 OP modes + * of the original YM3812 (AdLib). In addition the voice can + * be connected the left, right or both stereo channels. It can + * even be left unconnected. This works with 4 OP voices also. + * + * The stereo connection bits are located in the FEEDBACK_CONNECTION + * register of the voice (0xC0-0xC8). In 4 OP voices these bits are + * in the second half of the voice. + */ + +/* + * Register numbers for the global registers + */ + +#define TEST_REGISTER 0x01 +#define ENABLE_WAVE_SELECT 0x20 + +#define TIMER1_REGISTER 0x02 +#define TIMER2_REGISTER 0x03 +#define TIMER_CONTROL_REGISTER 0x04 /* Left side */ +#define IRQ_RESET 0x80 +#define TIMER1_MASK 0x40 +#define TIMER2_MASK 0x20 +#define TIMER1_START 0x01 +#define TIMER2_START 0x02 + +#define CONNECTION_SELECT_REGISTER 0x04 /* Right side */ +#define RIGHT_4OP_0 0x01 +#define RIGHT_4OP_1 0x02 +#define RIGHT_4OP_2 0x04 +#define LEFT_4OP_0 0x08 +#define LEFT_4OP_1 0x10 +#define LEFT_4OP_2 0x20 + +#define OPL3_MODE_REGISTER 0x05 /* Right side */ +#define OPL3_ENABLE 0x01 +#define OPL4_ENABLE 0x02 + +#define KBD_SPLIT_REGISTER 0x08 /* Left side */ +#define COMPOSITE_SINE_WAVE_MODE 0x80 /* Don't use with OPL-3? */ +#define KEYBOARD_SPLIT 0x40 + +#define PERCUSSION_REGISTER 0xbd /* Left side only */ +#define TREMOLO_DEPTH 0x80 +#define VIBRATO_DEPTH 0x40 +#define PERCOSSION_ENABLE 0x20 +#define BASSDRUM_ON 0x10 +#define SNAREDRUM_ON 0x08 +#define TOMTOM_ON 0x04 +#define CYMBAL_ON 0x02 +#define HIHAT_ON 0x01 + +/* + * Offsets to the register banks for operators. To get the + * register number just add the operator offset to the bank offset + * + * AM/VIB/EG/KSR/Multiple (0x20 to 0x35) + */ +#define AM_VIB 0x20 +#define TREMOLO_ON 0x80 +#define VIBRATO_ON 0x40 +#define SUSTAIN_ON 0x20 +#define KSR 0x10 /* Key scaling rate */ +#define MULTIPLE_MASK 0x0f /* Frequency multiplier */ + + /* + * KSL/Total level (0x40 to 0x55) + */ +#define KSL_LEVEL 0x40 +#define KSL_MASK 0xc0 /* Envelope scaling bits */ +#define TOTAL_LEVEL_MASK 0x3f /* Strength (volume) of OP */ + +/* + * Attack / Decay rate (0x60 to 0x75) + */ +#define ATTACK_DECAY 0x60 +#define ATTACK_MASK 0xf0 +#define DECAY_MASK 0x0f + +/* + * Sustain level / Release rate (0x80 to 0x95) + */ +#define SUSTAIN_RELEASE 0x80 +#define SUSTAIN_MASK 0xf0 +#define RELEASE_MASK 0x0f + +/* + * Wave select (0xE0 to 0xF5) + */ +#define WAVE_SELECT 0xe0 + +/* + * Offsets to the register banks for voices. Just add to the + * voice number to get the register number. + * + * F-Number low bits (0xA0 to 0xA8). + */ +#define FNUM_LOW 0xa0 + +/* + * F-number high bits / Key on / Block (octave) (0xB0 to 0xB8) + */ +#define KEYON_BLOCK 0xb0 +#define KEYON_BIT 0x20 +#define BLOCKNUM_MASK 0x1c +#define FNUM_HIGH_MASK 0x03 + +/* + * Feedback / Connection (0xc0 to 0xc8) + * + * These registers have two new bits when the OPL-3 mode + * is selected. These bits controls connecting the voice + * to the stereo channels. For 4 OP voices this bit is + * defined in the second half of the voice (add 3 to the + * register offset). + * + * For 4 OP voices the connection bit is used in the + * both halves (gives 4 ways to connect the operators). + */ +#define FEEDBACK_CONNECTION 0xc0 +#define FEEDBACK_MASK 0x0e /* Valid just for 1st OP of a voice */ +#define CONNECTION_BIT 0x01 +/* + * In the 4 OP mode there is four possible configurations how the + * operators can be connected together (in 2 OP modes there is just + * AM or FM). The 4 OP connection mode is defined by the rightmost + * bit of the FEEDBACK_CONNECTION (0xC0-0xC8) on the both halves. + * + * First half Second half Mode + * + * +---+ + * v | + * 0 0 >+-1-+--2--3--4--> + * + * + * + * +---+ + * | | + * 0 1 >+-1-+--2-+ + * |-> + * >--3----4-+ + * + * +---+ + * | | + * 1 0 >+-1-+-----+ + * |-> + * >--2--3--4-+ + * + * +---+ + * | | + * 1 1 >+-1-+--+ + * | + * >--2--3-+-> + * | + * >--4----+ + */ +#define STEREO_BITS 0x30 /* OPL-3 only */ +#define VOICE_TO_LEFT 0x10 +#define VOICE_TO_RIGHT 0x20 + +#endif + -- cgit v1.2.3