/* * c64cia2.c - Definitions for the second MOS6526 (CIA) chip in the C64 * ($DD00). * * Written by * Andre Fachat * Ettore Perazzoli * Andreas Boose * Marco van den Heuvel * * 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 #include "c64fastiec.h" #include "c64-resources.h" #include "c64.h" #include "c64mem.h" #include "c64iec.h" #include "c64cia.h" #include "c64gluelogic.h" #include "c64parallel.h" #include "cia.h" #include "drive.h" #include "iecbus.h" #include "interrupt.h" #include "keyboard.h" #include "lib.h" #include "log.h" #include "machine.h" #include "maincpu.h" #include "types.h" #include "userport.h" #include "vicii.h" /* Flag for recording port A DDR changes (for c64gluelogic) */ static int pa_ddr_change = 0; static uint8_t cia2_cra = 0; void cia2_store(uint16_t addr, uint8_t data) { if ((addr & 0xf) == CIA_CRA) { cia2_cra = data; } if (((addr & 0xf) == CIA_DDRA) && (machine_context.cia2->c_cia[CIA_DDRA] != data)) { pa_ddr_change = 1; } else { pa_ddr_change = 0; } ciacore_store(machine_context.cia2, addr, data); } uint8_t cia2_read(uint16_t addr) { return ciacore_read(machine_context.cia2, addr); } uint8_t cia2_peek(uint16_t addr) { return ciacore_peek(machine_context.cia2, addr); } static void cia_set_int_clk(cia_context_t *cia_context, int value, CLOCK clk) { interrupt_set_nmi(maincpu_int_status, cia_context->int_num, value, clk); } static void cia_restore_int(cia_context_t *cia_context, int value) { interrupt_restore_nmi(maincpu_int_status, cia_context->int_num, value); } void cia2_update_model(void) { if (machine_context.cia2) { machine_context.cia2->model = cia2_model; } } #define MYCIA CIA2 /************************************************************************* * I/O */ /* Current video bank (0, 1, 2 or 3). */ static int vbank; static void do_reset_cia(cia_context_t *cia_context) { store_userport_pbx(0xff, USERPORT_NO_PULSE); store_userport_pa2(1); vbank = 0; c64_glue_reset(); } static void pre_store(void) { vicii_handle_pending_alarms_external_write(); } static void pre_read(void) { vicii_handle_pending_alarms_external(0); } static void pre_peek(void) { vicii_handle_pending_alarms_external(0); } static void store_ciapa(cia_context_t *cia_context, CLOCK rclk, uint8_t byte) { if (cia_context->old_pa != byte) { uint8_t tmp; int new_vbank; if ((cia_context->old_pa ^ byte) & 4) { store_userport_pa2((uint8_t)((byte & 4) >> 2)); } if ((cia_context->old_pa ^ byte) & 8) { store_userport_pa3((uint8_t)((byte & 8) >> 3)); } tmp = (uint8_t)~byte; new_vbank = tmp & 3; if (new_vbank != vbank) { vbank = new_vbank; c64_glue_set_vbank(new_vbank, pa_ddr_change); } if (c64iec_active) { /* Bit 7 Serial Bus Data Input Bit 6 Serial Bus Clock Pulse Input Bit 5 Serial Bus Data Output Bit 4 Serial Bus Clock Pulse Output Bit 3 Serial Bus ATN Signal Output */ (*iecbus_callback_write)((uint8_t)tmp, maincpu_clk + !(cia_context->write_offset)); } } } static void undump_ciapa(cia_context_t *cia_context, CLOCK rclk, uint8_t byte) { store_userport_pa2((uint8_t)((byte & 4) >> 2)); store_userport_pa3((uint8_t)((byte & 8) >> 3)); vbank = (byte ^ 3) & 3; c64_glue_undump(vbank); if (c64iec_active) { iecbus_cpu_undump((uint8_t)(byte ^ 0xff)); } } static void store_ciapb(cia_context_t *cia_context, CLOCK rclk, uint8_t byte) { store_userport_pbx(byte, USERPORT_NO_PULSE); } static void pulse_ciapc(cia_context_t *cia_context, CLOCK rclk) { store_userport_pbx((uint8_t)(cia_context->old_pb), USERPORT_PULSE); } /* FIXME! */ static inline void undump_ciapb(cia_context_t *cia_context, CLOCK rclk, uint8_t byte) { store_userport_pbx(byte, USERPORT_NO_PULSE); /* The functions below will gradually be removed as the functionality is added to the new userport system. */ parallel_cable_cpu_undump(DRIVE_PC_STANDARD, (uint8_t)byte); } /* read_* functions must return 0xff if nothing to read!!! */ static uint8_t read_ciapa(cia_context_t *cia_context) { uint8_t value; uint8_t userval = 1; value = ((cia_context->c_cia[CIA_PRA] | ~(cia_context->c_cia[CIA_DDRA])) & 0x3f); if (c64iec_active) { /* Bit 7 Serial Bus Data Input Bit 6 Serial Bus Clock Pulse Input Bit 5 Serial Bus Data Output Bit 4 Serial Bus Clock Pulse Output Bit 3 Serial Bus ATN Signal Output */ value |= (*iecbus_callback_read)(maincpu_clk); } if (!(cia_context->c_cia[CIA_DDRA] & 4)) { userval = read_userport_pa2(userval); if (value != userval) { value &= (userval & 1) ? 0xff : 0xfb; } } if (!(cia_context->c_cia[CIA_DDRA] & 8)) { userval = read_userport_pa3(userval); if (value != userval) { value &= (userval & 1) ? 0xff : 0xf7; } } return value; } /* read_* functions must return 0xff if nothing to read!!! */ static uint8_t read_ciapb(cia_context_t *cia_context) { uint8_t byte = 0xff; byte = read_userport_pbx(byte); byte = (byte & ~(cia_context->c_cia[CIA_DDRB])) | (cia_context->c_cia[CIA_PRB] & cia_context->c_cia[CIA_DDRB]); return byte; } static void read_ciaicr(cia_context_t *cia_context) { if (burst_mod == BURST_MOD_CIA2) { drive_cpu_execute_all(maincpu_clk); } parallel_cable_cpu_execute(DRIVE_PC_STANDARD); } static void read_sdr(cia_context_t *cia_context) { if (burst_mod == BURST_MOD_CIA2) { drive_cpu_execute_all(maincpu_clk); } cia_context->c_cia[CIA_SDR] = read_userport_sp2(cia_context->c_cia[CIA_SDR]); } static void store_sdr(cia_context_t *cia_context, uint8_t byte) { if ((cia2_cra & 0x59) == 0x51) { store_userport_sp2(byte); } if (c64iec_active) { if (burst_mod == BURST_MOD_CIA2) { c64fastiec_fast_cpu_write((uint8_t)byte); } } } /* Temporary! */ void cia2_set_flagx(void) { ciacore_set_flag(machine_context.cia2); } void cia2_set_sdrx(uint8_t received_byte) { ciacore_set_sdr(machine_context.cia2, received_byte); } void cia2_init(cia_context_t *cia_context) { ciacore_init(machine_context.cia2, maincpu_alarm_context, maincpu_int_status); } void cia2_setup_context(machine_context_t *machinecontext) { cia_context_t *cia; machinecontext->cia2 = lib_calloc(1, sizeof(cia_context_t)); cia = machinecontext->cia2; cia->prv = NULL; cia->context = NULL; cia->rmw_flag = &maincpu_rmw_flag; cia->clk_ptr = &maincpu_clk; cia2_set_timing(cia, C64_PAL_CYCLES_PER_SEC, 50); ciacore_setup_context(cia); if (machine_class == VICE_MACHINE_C64SC || machine_class == VICE_MACHINE_SCPU64) { cia->write_offset = 0; } cia->model = cia2_model; cia->debugFlag = 0; cia->irq_line = IK_NMI; cia->myname = lib_msprintf("CIA2"); cia->undump_ciapa = undump_ciapa; cia->undump_ciapb = undump_ciapb; cia->store_ciapa = store_ciapa; cia->store_ciapb = store_ciapb; cia->store_sdr = store_sdr; cia->read_ciapa = read_ciapa; cia->read_ciapb = read_ciapb; cia->read_ciaicr = read_ciaicr; cia->read_sdr = read_sdr; cia->cia_set_int_clk = cia_set_int_clk; cia->cia_restore_int = cia_restore_int; cia->do_reset_cia = do_reset_cia; cia->pulse_ciapc = pulse_ciapc; cia->pre_store = pre_store; cia->pre_read = pre_read; cia->pre_peek = pre_peek; } void cia2_set_timing(cia_context_t *cia_context, int tickspersec, int powerfreq) { cia_context->power_freq = powerfreq; cia_context->ticks_per_sec = tickspersec; cia_context->todticks = tickspersec / powerfreq; cia_context->power_tickcounter = 0; cia_context->power_ticks = 0; }