#pragma once #ifndef __FLT_RC_H__ #define __FLT_RC_H__ #include "machine/rescap.h" /* * FLT_RC_LOWPASS: * * signal >--R1--+--R2--+ * | | * C R3---> amp * | | * GND GND * * Set C=0 to disable filter * * FLT_RC_HIGHPASS: * * signal >--C---+----> amp * | * R1 * | * GND * * Set C = 0 to disable filter * * FLT_RC_AC: * * Same as FLT_RC_HIGHPASS, but with standard frequency of 16 HZ * This filter may be setup just with * * MCFG_SOUND_ADD("tag", FILTER_RC, 0) * MCFG_SOUND_CONFIG(&flt_rc_ac_default) * * Default behaviour: * * Without MCFG_SOUND_CONFIG, a disabled FLT_RC_LOWPASS is created * */ //************************************************************************** // INTERFACE CONFIGURATION MACROS //************************************************************************** #define MCFG_FILTER_RC_ADD(_tag, _clock) \ MCFG_DEVICE_ADD(_tag, FILTER_RC, _clock) #define MCFG_FILTER_RC_REPLACE(_tag, _clock) \ MCFG_DEVICE_REPLACE(_tag, FILTER_RC, _clock) //************************************************************************** // TYPE DEFINITIONS //************************************************************************** #define FLT_RC_LOWPASS 0 #define FLT_RC_HIGHPASS 1 #define FLT_RC_AC 2 struct flt_rc_config { int type; double R1; double R2; double R3; double C; }; extern const flt_rc_config flt_rc_ac_default; // ======================> filter_rc_device class filter_rc_device : public device_t, public device_sound_interface { public: filter_rc_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock); ~filter_rc_device() { } void filter_rc_set_RC(int type, double R1, double R2, double R3, double C); protected: // device-level overrides virtual void device_start(); // sound stream update overrides virtual void sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples); private: void set_RC_info(int type, double R1, double R2, double R3, double C); private: sound_stream* m_stream; int m_k; int m_memory; int m_type; }; extern const device_type FILTER_RC; #endif /* __FLT_RC_H__ */