Mercurial > repos > simple16
view src/main.c @ 25:fb14515266f4
Implemented timer and timer interrupts. Added get/setvbr instructions. Fixed assembler bug. Moved mnemonics into a separate source file
author | Michael Pavone <pavone@retrodev.com> |
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date | Thu, 31 Mar 2016 23:25:52 -0700 |
parents | 4c9dbfa30a66 |
children | 083347ccd508 |
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#include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include "cpu.h" #include "vdp.h" #include "audio.h" #include "timer.h" #include "system.h" #define CYCLES_PER_FRAME (832*262) #define MASTER_CLOCK 13056000 uint8_t rom[48 * 1024]; uint8_t ram[16 * 1024]; enum { PORT_CONTROLLER_1, PORT_CONTROLLER_2, PORT_CONTROLLER_3, PORT_CONTROLLER_4, PORT_FREQUENCY_A, PORT_FREQUENCY_B, PORT_FREQUENCY_C, PORT_FREQUENCY_D, PORT_VOLUME_AB, PORT_VOLUME_CD, PORT_TIMER, PORT_SERIAL, PORT_VERTICAL, PORT_HORIZONTAL, PORT_VRAM_ADDRESS, PORT_VRAM_DATA }; typedef struct { cpu *proc; audio *audio; timer timer; vdp video; } console; void debug_port_write(cpu *context, uint8_t port, uint16_t value) { putchar(value); } uint16_t debug_port_read(cpu *context, uint8_t port) { return getchar(); } void vertical_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; vdp_run(&system->video, context->cycles); system->video.vscroll = value; } uint16_t vertical_port_read(cpu *context, uint8_t port) { console *system = context->system; vdp_run(&system->video, context->cycles); return system->video.vcounter; } void horizontal_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; vdp_run(&system->video, context->cycles); vdp_write_hscroll(&system->video, value); } uint16_t horizontal_port_read(cpu *context, uint8_t port) { console *system = context->system; vdp_run(&system->video, context->cycles); return system->video.hcounter; } void address_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; vdp_run(&system->video, context->cycles); vdp_write_address(&system->video, value); } uint16_t address_port_read(cpu *context, uint8_t port) { console *system = context->system; vdp_run(&system->video, context->cycles); return system->video.status; } void data_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; vdp_run(&system->video, context->cycles); vdp_write_data(&system->video, value); } void frequency_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; audio_run(system->audio, context->cycles); audio_write_freq(system->audio, port - PORT_FREQUENCY_A, value); } void volume_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; audio_run(system->audio, context->cycles); audio_write_vol(system->audio, port - PORT_VOLUME_AB, value); } void timer_port_write(cpu *context, uint8_t port, uint16_t value) { console *system = context->system; timer_run(&system->timer, context->cycles); timer_write(&system->timer, value); uint32_t next_int = next_interrupt_cycle(context, (~context->pending_interrupts) & 3); if (next_int < context->current_target) { context->current_target = next_int; } } uint32_t next_interrupt_cycle(cpu *context, uint8_t mask) { console *system = context->system; uint32_t next = 0xFFFFFFFF; if (mask & 1) { timer_run(&system->timer, context->cycles); next = timer_next_interrupt(&system->timer); } if (mask & 2) { vdp_run(&system->video, context->cycles); //TODO: VBlank interrupt } return next; } uint8_t get_current_interrupts(cpu *context) { console *system = context->system; timer_run(&system->timer, context->cycles); uint8_t bits = 0; if (system->timer.pending) { bits |= 1; } vdp_run(&system->video, context->cycles); //TODO: VBlank interrupt return bits; } void ack_interrupt(cpu *context, int which) { console *system = context->system; if (which == 0) { timer_run(&system->timer, context->cycles); system->timer.pending = 0; } //TODO: VBlank interrupt } memory_region regions[] = { {rom, 0, sizeof(rom)-1, MEM_READ}, {ram, sizeof(rom), sizeof(rom)-1+sizeof(ram), MEM_READ}, }; void run_console(console *context) { for(;;) { run_cpu(context->proc, CYCLES_PER_FRAME); audio_run(context->audio, CYCLES_PER_FRAME); vdp_run(&context->video, CYCLES_PER_FRAME); timer_run(&context->timer, CYCLES_PER_FRAME); context->proc->cycles -= CYCLES_PER_FRAME; context->video.cycles -= CYCLES_PER_FRAME; context->audio->cycles -= CYCLES_PER_FRAME; context->timer.cycles -= CYCLES_PER_FRAME; system_poll_events(); } } int main(int argc, char **argv) { if (argc < 2) { fputs("usage: s16 FILE\n", stderr); return 1; } FILE *f = fopen(argv[1], "rb"); if (!f) { fprintf(stderr, "Failed to open %s for reading\n", argv[1]); return 1; } size_t read; if ((read = fread(rom, 1, sizeof(rom), f)) < sizeof(rom)) { memset(rom + read, 0xFF, sizeof(rom)-read); } console context; context.proc = alloc_cpu(10, sizeof(regions)/sizeof(memory_region), regions); context.proc->system = &context; vdp_init(&context.video, 2); timer_init(&context.timer, 16); context.proc->port_handlers[PORT_FREQUENCY_A].write = frequency_port_write; context.proc->port_handlers[PORT_FREQUENCY_B].write = frequency_port_write; context.proc->port_handlers[PORT_FREQUENCY_C].write = frequency_port_write; context.proc->port_handlers[PORT_FREQUENCY_D].write = frequency_port_write; context.proc->port_handlers[PORT_VOLUME_AB].write = volume_port_write; context.proc->port_handlers[PORT_VOLUME_CD].write = volume_port_write; context.proc->port_handlers[PORT_TIMER].write = timer_port_write; context.proc->port_handlers[PORT_SERIAL].write = debug_port_write; context.proc->port_handlers[PORT_SERIAL].read = debug_port_read; context.proc->port_handlers[PORT_VERTICAL].write = vertical_port_write; context.proc->port_handlers[PORT_VERTICAL].read = vertical_port_read; context.proc->port_handlers[PORT_HORIZONTAL].write = horizontal_port_write; context.proc->port_handlers[PORT_HORIZONTAL].read = horizontal_port_read; context.proc->port_handlers[PORT_VRAM_ADDRESS].write = address_port_write; context.proc->port_handlers[PORT_VRAM_ADDRESS].read = address_port_read; context.proc->port_handlers[PORT_VRAM_DATA].write = data_port_write; if (!system_init(640, 480, 48000)) { return 1; } context.audio = alloc_audio(MASTER_CLOCK, 17, system_sample_rate(), system_buffer_size()); run_console(&context); return 0; }