ay8910.h

#ifndef __LIBDRAGON_AY8910_H
#define __LIBDRAGON_AY8910_H
 
#include <stdbool.h>
#include <stdint.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
#define AY8910_DECIMATE           3
 
#define AY8910_OUTPUT_STEREO      1
 
#define AY8910_VOLUME_ATTENUATE   0.8
 
#define AY8910_CENTER_SILENCE     1
 
typedef struct {
    uint16_t tone_period;      
    uint8_t tone_vol;          
    uint8_t tone_en;           
    uint8_t noise_en;          
 
    uint16_t count;            
    uint8_t out;               
} AYChannel;
 
typedef struct {
    uint16_t period;           
    uint8_t shape;             
 
    uint8_t attack;            
    uint8_t alternate;         
    uint8_t hold;              
 
    uint16_t count;            
    int16_t step;              
    uint8_t vol;               
    uint8_t holding;           
} AYEnvelope;
 
typedef struct {
    uint8_t period;            
 
    uint8_t count;             
    uint32_t out;              
} AYNoise;
 
typedef struct {
    uint8_t (*PortRead)(int idx);             
    void (*PortWrite)(int idx, uint8_t val);  
    uint8_t addr;                             
    uint8_t regs[16];                         
    AYChannel ch[3];                          
    AYNoise ns;                               
    AYEnvelope env;                           
} AY8910;
 
void ay8910_reset(AY8910 *ay);
 
void ay8910_set_ports(AY8910 *ay, uint8_t (*PortRead)(int), void (*PortWrite)(int, uint8_t));
 
void ay8910_write_addr(AY8910 *ay, uint8_t addr);
 
void ay8910_write_data(AY8910 *ay, uint8_t val);
 
uint8_t ay8910_read_data(AY8910 *ay);
 
bool ay8910_is_mute(AY8910 *ay);
 
int ay8910_gen(AY8910 *ay, int16_t *out, int nsamples);
 
#ifdef __cplusplus
}
#endif
 
#endif