/* * vicii-irq.c - IRQ related functions for the MOS 6569 (VIC-II) emulation. * * Written by * Andreas Boose * Ettore Perazzoli * * DTV sections written by * Hannu Nuotio * * This file is part of VICE, the Versatile Commodore Emulator. * See README for copyright notice. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA * 02111-1307 USA. * */ #include "vice.h" #include "alarm.h" #include "interrupt.h" #include "maincpu.h" #include "types.h" #include "vicii-irq.h" #include "viciitypes.h" #include "c64dtvblitter.h" #include "c64dtvdma.h" void vicii_irq_set_line(void) { if (vicii.irq_status & vicii.regs[0x1a]) { vicii.irq_status |= 0x80; maincpu_set_irq(vicii.int_num, 1); } else { vicii.irq_status &= 0x7f; maincpu_set_irq(vicii.int_num, 0); } } static inline void vicii_irq_set_line_clk(CLOCK mclk) { if (vicii.irq_status & vicii.regs[0x1a]) { vicii.irq_status |= 0x80; maincpu_set_irq_clk(vicii.int_num, 1, mclk); } else { vicii.irq_status &= 0x7f; maincpu_set_irq_clk(vicii.int_num, 0, mclk); } } void vicii_irq_raster_set(CLOCK mclk) { vicii.irq_status |= 0x1; vicii_irq_set_line_clk(mclk); } void vicii_irq_raster_clear(CLOCK mclk) { vicii.irq_status &= 0xfe; vicii_irq_set_line_clk(mclk); } void vicii_irq_sbcoll_set(void) { vicii.irq_status |= 0x2; vicii_irq_set_line(); } void vicii_irq_sbcoll_clear(void) { vicii.irq_status &= 0xfd; vicii_irq_set_line(); } void vicii_irq_sscoll_set(void) { vicii.irq_status |= 0x4; vicii_irq_set_line(); } void vicii_irq_sscoll_clear(void) { vicii.irq_status &= 0xfb; vicii_irq_set_line(); } void vicii_irq_lightpen_set(CLOCK mclk) { vicii.irq_status |= 0x8; vicii_irq_set_line_clk(mclk); } void vicii_irq_lightpen_clear(CLOCK mclk) { vicii.irq_status &= 0xf7; vicii_irq_set_line_clk(mclk); } void vicii_irq_set_raster_line(unsigned int line) { if (vicii.raster_irq_prevent) { vicii.raster_irq_clk = CLOCK_MAX; alarm_unset(vicii.raster_irq_alarm); return; } if (line == vicii.raster_irq_line && vicii.raster_irq_clk != CLOCK_MAX) { return; } if (line < (unsigned int)vicii.screen_height) { unsigned int current_line = VICII_RASTER_Y(maincpu_clk); if (line > current_line) { vicii.raster_irq_clk = (VICII_LINE_START_CLK(maincpu_clk) + VICII_RASTER_IRQ_DELAY - INTERRUPT_DELAY + (vicii.cycles_per_line * (line - current_line))); } else { vicii.raster_irq_clk = (VICII_LINE_START_CLK(maincpu_clk) + VICII_RASTER_IRQ_DELAY - INTERRUPT_DELAY + (vicii.cycles_per_line * (line + vicii.screen_height - current_line))); } if (vicii.viciidtv) { vicii.raster_irq_clk += vicii.raster_irq_offset; } /* Raster interrupts on line 0 are delayed by 1 cycle. */ if (line == 0) { vicii.raster_irq_clk++; } alarm_set(vicii.raster_irq_alarm, vicii.raster_irq_clk); } else { VICII_DEBUG_RASTER(("update_raster_irq(): " "raster compare out of range ($%04X)!", line)); vicii.raster_irq_clk = CLOCK_MAX; alarm_unset(vicii.raster_irq_alarm); } VICII_DEBUG_RASTER(("update_raster_irq(): " "vicii.raster_irq_clk = %ul, " "line = $%04X, " "vicii.regs[0x1a] & 1 = %d", vicii.raster_irq_clk, line, vicii.regs[0x1a] & 1)); vicii.raster_irq_line = line; } void vicii_irq_check_state(uint8_t value, unsigned int high) { unsigned int irq_line, line; unsigned int old_raster_irq_line; CLOCK old_raster_irq_clk = vicii.raster_irq_clk; if (high) { irq_line = (vicii.raster_irq_line & 0xff) | ((value & 0x80) << 1); } else { irq_line = (vicii.raster_irq_line & 0x100) | value; } if (irq_line == vicii.raster_irq_line) { return; } line = VICII_RASTER_Y(maincpu_clk); old_raster_irq_line = vicii.raster_irq_line; vicii_irq_set_raster_line(irq_line); if (vicii.regs[0x1a] & 0x1) { int trigger_irq; trigger_irq = 0; if (old_raster_irq_clk == VICII_LINE_START_CLK(maincpu_clk) + (line == 0 ? 1 : 0)) { trigger_irq = 2; } if (maincpu_rmw_flag) { if (high) { if (VICII_RASTER_CYCLE(maincpu_clk) == 0 && (line & 0xff) == 0) { unsigned int previous_line = VICII_PREVIOUS_LINE(line); if (previous_line != old_raster_irq_line && ((old_raster_irq_line & 0xff) == (previous_line & 0xff))) { trigger_irq = 1; } } else { if (line != old_raster_irq_line && (old_raster_irq_line & 0xff) == (line & 0xff)) { trigger_irq = 1; } } } else { if (VICII_RASTER_CYCLE(maincpu_clk) == 0) { unsigned int previous_line = VICII_PREVIOUS_LINE(line); if (previous_line != old_raster_irq_line && ((old_raster_irq_line & 0x100) == (previous_line & 0x100))) { trigger_irq = 1; } } else { if (line != old_raster_irq_line && (old_raster_irq_line & 0x100) == (line & 0x100)) { trigger_irq = 1; } } } } if (vicii.raster_irq_line == line && line != old_raster_irq_line) { trigger_irq = 1; } if (trigger_irq == 1) { vicii_irq_raster_set(maincpu_clk); } if (trigger_irq == 2) { vicii_irq_raster_set(old_raster_irq_clk); } } } void vicii_irq_next_frame(void) { vicii.raster_irq_clk += vicii.screen_height * vicii.cycles_per_line; alarm_set(vicii.raster_irq_alarm, vicii.raster_irq_clk); } /* If necessary, emulate a raster compare IRQ. This is called when the raster line counter matches the value stored in the raster line register. */ void vicii_irq_alarm_handler(CLOCK offset, void *data) { /* Scheduled Blitter */ if (blitter_on_irq & 0x10) { c64dtvblitter_trigger_blitter(); } /* Scheduled DMA */ if (dma_on_irq & 0x10) { c64dtvdma_trigger_dma(); } vicii_irq_raster_set(vicii.raster_irq_clk); vicii_irq_next_frame(); } void vicii_irq_init(void) { vicii.int_num = interrupt_cpu_status_int_new(maincpu_int_status, "VICII"); vicii.raster_irq_alarm = alarm_new(maincpu_alarm_context, "VicIIRasterIrq", vicii_irq_alarm_handler, NULL); }