ref: f4abf51e5c0c6dc4768e38fb2958d21e01af797a
dir: /opl/opl.h/
// // Copyright(C) 2005-2014 Simon Howard // // This program is free software; you can redistribute it and/or // modify it under the terms of the GNU General Public License // as published by the Free Software Foundation; either version 2 // of the License, or (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // DESCRIPTION: // OPL interface. // #ifndef OPL_OPL_H #define OPL_OPL_H #include <inttypes.h> typedef void (*opl_callback_t)(void *data); // Result from OPL_Init(), indicating what type of OPL chip was detected, // if any. typedef enum { OPL_INIT_NONE, OPL_INIT_OPL2, OPL_INIT_OPL3, } opl_init_result_t; typedef enum { OPL_REGISTER_PORT = 0, OPL_DATA_PORT = 1, OPL_REGISTER_PORT_OPL3 = 2 } opl_port_t; #define OPL_NUM_OPERATORS 21 #define OPL_NUM_VOICES 9 #define OPL_REG_WAVEFORM_ENABLE 0x01 #define OPL_REG_TIMER1 0x02 #define OPL_REG_TIMER2 0x03 #define OPL_REG_TIMER_CTRL 0x04 #define OPL_REG_FM_MODE 0x08 #define OPL_REG_NEW 0x105 // Operator registers (21 of each): #define OPL_REGS_TREMOLO 0x20 #define OPL_REGS_LEVEL 0x40 #define OPL_REGS_ATTACK 0x60 #define OPL_REGS_SUSTAIN 0x80 #define OPL_REGS_WAVEFORM 0xE0 // Voice registers (9 of each): #define OPL_REGS_FREQ_1 0xA0 #define OPL_REGS_FREQ_2 0xB0 #define OPL_REGS_FEEDBACK 0xC0 // Times #define OPL_SECOND ((uint64_t) 1000 * 1000) #define OPL_MS ((uint64_t) 1000) #define OPL_US ((uint64_t) 1) // // Low-level functions. // // Initialize the OPL subsystem. opl_init_result_t OPL_Init(unsigned int port_base); // Shut down the OPL subsystem. void OPL_Shutdown(void); // Set the sample rate used for software emulation. void OPL_SetSampleRate(unsigned int rate); // Write to one of the OPL I/O ports: void OPL_WritePort(opl_port_t port, unsigned int value); // Read from one of the OPL I/O ports: unsigned int OPL_ReadPort(opl_port_t port); // // Higher-level functions. // // Read the cuurrent status byte of the OPL chip. unsigned int OPL_ReadStatus(void); // Write to an OPL register. void OPL_WriteRegister(int reg, int value); // Perform a detection sequence to determine that an // OPL chip is present. opl_init_result_t OPL_Detect(void); // Initialize all registers, performed on startup. void OPL_InitRegisters(int opl3); // // Timer callback functions. // // Set a timer callback. After the specified number of microseconds // have elapsed, the callback will be invoked. void OPL_SetCallback(uint64_t us, opl_callback_t callback, void *data); // Adjust callback times by the specified factor. For example, a value of // 0.5 will halve all remaining times. void OPL_AdjustCallbacks(float factor); // Clear all OPL callbacks that have been set. void OPL_ClearCallbacks(void); // Begin critical section, during which, OPL callbacks will not be // invoked. void OPL_Lock(void); // End critical section. void OPL_Unlock(void); // Block until the specified number of microseconds have elapsed. void OPL_Delay(uint64_t us); // Pause the OPL callbacks. void OPL_SetPaused(int paused); #endif