mirror of
https://github.com/TomHarte/CLK.git
synced 2024-08-16 16:28:59 +00:00
167 lines
3.8 KiB
C++
167 lines
3.8 KiB
C++
//
|
|
// ZX8081.cpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 04/06/2017.
|
|
// Copyright © 2017 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#include "ZX8081.hpp"
|
|
|
|
#include "../MemoryFuzzer.hpp"
|
|
|
|
using namespace ZX8081;
|
|
|
|
namespace {
|
|
const unsigned int ZX8081ClockRate = 3250000;
|
|
}
|
|
|
|
Machine::Machine() :
|
|
vsync_(false),
|
|
hsync_(false),
|
|
ram_(1024),
|
|
key_states_{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
|
|
tape_player_(ZX8081ClockRate) {
|
|
// run at 3.25 Mhz
|
|
set_clock_rate(ZX8081ClockRate);
|
|
Memory::Fuzz(ram_);
|
|
tape_player_.set_motor_control(true);
|
|
}
|
|
|
|
int Machine::perform_machine_cycle(const CPU::Z80::MachineCycle &cycle) {
|
|
video_->run_for_cycles(cycle.length);
|
|
tape_player_.run_for_cycles(cycle.length);
|
|
|
|
uint16_t refresh = 0;
|
|
uint16_t address = cycle.address ? *cycle.address : 0;
|
|
switch(cycle.operation) {
|
|
case CPU::Z80::BusOperation::Output:
|
|
// if((address&7) == 7) {
|
|
set_vsync(false);
|
|
line_counter_ = 0;
|
|
// }
|
|
break;
|
|
|
|
case CPU::Z80::BusOperation::Input: {
|
|
uint8_t value = 0xff;
|
|
if(!(address&1)) {
|
|
set_vsync(true);
|
|
|
|
uint16_t mask = 0x100;
|
|
for(int c = 0; c < 8; c++) {
|
|
if(!(address & mask)) value &= key_states_[c];
|
|
mask <<= 1;
|
|
}
|
|
|
|
value &= ~(tape_player_.get_input() ? 0x00 : 0x80);
|
|
}
|
|
*cycle.value = value;
|
|
} break;
|
|
|
|
case CPU::Z80::BusOperation::Interrupt:
|
|
set_hsync(true);
|
|
line_counter_ = (line_counter_ + 1) & 7;
|
|
*cycle.value = 0xff;
|
|
break;
|
|
|
|
case CPU::Z80::BusOperation::ReadOpcode:
|
|
set_hsync(false);
|
|
refresh = get_value_of_register(CPU::Z80::Register::Refresh);
|
|
set_interrupt_line(!(refresh & 0x40));
|
|
case CPU::Z80::BusOperation::Read:
|
|
if((address & 0xc000) == 0x0000) *cycle.value = rom_[address & (rom_.size() - 1)];
|
|
else if((address & 0x4000) == 0x4000) {
|
|
uint8_t value = ram_[address & 1023];
|
|
if(address&0x8000 && !(value & 0x40) && cycle.operation == CPU::Z80::BusOperation::ReadOpcode && !get_halt_line()) {
|
|
size_t char_address = (size_t)((refresh & 0xff00) | ((value & 0x3f) << 3) | line_counter_);
|
|
if((char_address & 0xc000) == 0x0000) {
|
|
uint8_t mask = (value & 0x80) ? 0x00 : 0xff;
|
|
value = rom_[char_address & (rom_.size() - 1)] ^ mask;
|
|
}
|
|
|
|
video_->output_byte(value);
|
|
*cycle.value = 0;
|
|
} else *cycle.value = value;
|
|
}
|
|
break;
|
|
|
|
case CPU::Z80::BusOperation::Write:
|
|
if((address & 0x4000) == 0x4000) ram_[address & 1023] = *cycle.value;
|
|
break;
|
|
|
|
default: break;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void Machine::flush() {
|
|
video_->flush();
|
|
}
|
|
|
|
void Machine::setup_output(float aspect_ratio) {
|
|
video_.reset(new Video);
|
|
}
|
|
|
|
void Machine::close_output() {
|
|
video_.reset();
|
|
}
|
|
|
|
std::shared_ptr<Outputs::CRT::CRT> Machine::get_crt() {
|
|
return video_->get_crt();
|
|
}
|
|
|
|
std::shared_ptr<Outputs::Speaker> Machine::get_speaker() {
|
|
return nullptr;
|
|
}
|
|
|
|
void Machine::run_for_cycles(int number_of_cycles) {
|
|
CPU::Z80::Processor<Machine>::run_for_cycles(number_of_cycles);
|
|
}
|
|
|
|
void Machine::configure_as_target(const StaticAnalyser::Target &target) {
|
|
// TODO: pay attention to the target; it can't currently specify a ZX81
|
|
// so assume a ZX80 if we got here.
|
|
rom_ = zx80_rom_;
|
|
|
|
if(target.tapes.size()) {
|
|
tape_player_.set_tape(target.tapes.front());
|
|
}
|
|
}
|
|
|
|
void Machine::set_rom(ROMType type, std::vector<uint8_t> data) {
|
|
switch(type) {
|
|
case ZX80: zx80_rom_ = data; break;
|
|
case ZX81: zx81_rom_ = data; break;
|
|
}
|
|
}
|
|
|
|
#pragma mark - Video
|
|
|
|
void Machine::set_vsync(bool sync) {
|
|
vsync_ = sync;
|
|
update_sync();
|
|
}
|
|
|
|
void Machine::set_hsync(bool sync) {
|
|
hsync_ = sync;
|
|
update_sync();
|
|
}
|
|
|
|
void Machine::update_sync() {
|
|
video_->set_sync(vsync_ || hsync_);
|
|
}
|
|
|
|
#pragma mark - Keyboard
|
|
|
|
void Machine::set_key_state(uint16_t key, bool isPressed) {
|
|
if(isPressed)
|
|
key_states_[key >> 8] &= (uint8_t)(~key);
|
|
else
|
|
key_states_[key >> 8] |= (uint8_t)key;
|
|
}
|
|
|
|
void Machine::clear_all_keys() {
|
|
memset(key_states_, 0xff, 8);
|
|
}
|