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931 lines
28 KiB
C++
931 lines
28 KiB
C++
//
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// Electron.cpp
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// Clock Signal
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//
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// Created by Thomas Harte on 03/01/2016.
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// Copyright © 2016 Thomas Harte. All rights reserved.
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//
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#include "Electron.hpp"
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#include "TapeUEF.hpp"
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#include <algorithm>
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#include <cassert>
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using namespace Electron;
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namespace {
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static const unsigned int cycles_per_line = 128;
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static const unsigned int lines_per_frame = 625;
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static const unsigned int cycles_per_frame = lines_per_frame * cycles_per_line;
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static const unsigned int crt_cycles_multiplier = 8;
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static const unsigned int crt_cycles_per_line = crt_cycles_multiplier * cycles_per_line;
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static const unsigned int field_divider_line = 312; // i.e. the line, simultaneous with which, the first field's sync ends. So if
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// the first line with pixels in field 1 is the 20th in the frame, the first line
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// with pixels in field 2 will be 20+field_divider_line
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static const unsigned int first_graphics_line = 31;
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static const unsigned int first_graphics_cycle = 33;
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static const unsigned int display_end_interrupt_line = 256;
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static const unsigned int real_time_clock_interrupt_1 = 16704;
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static const unsigned int real_time_clock_interrupt_2 = 56704;
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}
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#define graphics_line(v) ((((v) >> 7) - first_graphics_line + field_divider_line) % field_divider_line)
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#define graphics_column(v) ((((v) & 127) - first_graphics_cycle + 128) & 127)
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Machine::Machine() :
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interrupt_control_(0),
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interrupt_status_(Interrupt::PowerOnReset | Interrupt::TransmitDataEmpty | 0x80),
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frame_cycles_(0),
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display_output_position_(0),
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audio_output_position_(0),
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current_pixel_line_(-1),
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use_fast_tape_hack_(false),
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phase_(0)
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{
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memset(key_states_, 0, sizeof(key_states_));
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memset(palette_, 0xf, sizeof(palette_));
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for(int c = 0; c < 16; c++)
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memset(roms_[c], 0xff, 16384);
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tape_.set_delegate(this);
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set_clock_rate(2000000);
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}
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void Machine::setup_output(float aspect_ratio)
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{
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speaker_.reset(new Speaker);
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crt_.reset(new Outputs::CRT::CRT(crt_cycles_per_line, 8, Outputs::CRT::DisplayType::PAL50, 1));
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crt_->set_rgb_sampling_function(
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"vec3 rgb_sample(usampler2D sampler, vec2 coordinate, vec2 icoordinate)"
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"{"
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"uint texValue = texture(sampler, coordinate).r;"
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"texValue >>= 4 - (int(icoordinate.x * 8) & 4);"
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"return vec3( uvec3(texValue) & uvec3(4u, 2u, 1u));"
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"}");
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// TODO: as implied below, I've introduced a clock's latency into the graphics pipeline somehow. Investigate.
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crt_->set_visible_area(crt_->get_rect_for_area(first_graphics_line - 3, 256, (first_graphics_cycle+1) * crt_cycles_multiplier, 80 * crt_cycles_multiplier, 4.0f / 3.0f));
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// The maximum output frequency is 62500Hz and all other permitted output frequencies are integral divisions of that;
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// however setting the speaker on or off can happen on any 2Mhz cycle, and probably (?) takes effect immediately. So
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// run the speaker at a 2000000Hz input rate, at least for the time being.
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speaker_->set_input_rate(2000000 / Speaker::clock_rate_divider);
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}
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void Machine::close_output()
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{
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crt_ = nullptr;
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}
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unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uint16_t address, uint8_t *value)
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{
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unsigned int cycles = 1;
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if(address < 0x8000)
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{
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if(isReadOperation(operation))
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{
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*value = ram_[address];
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}
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else
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{
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if(
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(
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((frame_cycles_ >= first_graphics_line * cycles_per_line) && (frame_cycles_ < (first_graphics_line + 256) * cycles_per_line)) ||
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((frame_cycles_ >= (first_graphics_line + field_divider_line) * cycles_per_line) && (frame_cycles_ < (first_graphics_line + 256 + field_divider_line) * cycles_per_line))
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)
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)
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update_display();
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ram_[address] = *value;
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}
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// for the entire frame, RAM is accessible only on odd cycles; in modes below 4
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// it's also accessible only outside of the pixel regions
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cycles += 1 + (frame_cycles_&1);
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if(screen_mode_ < 4)
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{
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const int current_line = graphics_line(frame_cycles_ + (frame_cycles_&1));
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const int current_column = graphics_column(frame_cycles_ + (frame_cycles_&1));
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if(current_line < 256 && current_column < 80 && !is_blank_line_)
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cycles += (unsigned int)(80 - current_column);
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}
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}
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else
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{
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// if((address >> 8) == 0xfc)
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// {
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// printf("d");
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// }
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switch(address & 0xff0f)
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{
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case 0xfe00:
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if(isReadOperation(operation))
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{
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*value = interrupt_status_;
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interrupt_status_ &= ~PowerOnReset;
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}
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else
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{
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interrupt_control_ = (*value) & ~1;
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evaluate_interrupts();
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}
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break;
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case 0xfe02:
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if(!isReadOperation(operation))
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{
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start_screen_address_ = (start_screen_address_ & 0xfe00) | (uint16_t)(((*value) & 0xe0) << 1);
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if(!start_screen_address_) start_screen_address_ |= 0x8000;
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}
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break;
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case 0xfe03:
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if(!isReadOperation(operation))
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{
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start_screen_address_ = (start_screen_address_ & 0x01ff) | (uint16_t)(((*value) & 0x3f) << 9);
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if(!start_screen_address_) start_screen_address_ |= 0x8000;
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}
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break;
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case 0xfe04:
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if(isReadOperation(operation))
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{
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*value = tape_.get_data_register();
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tape_.clear_interrupts(Interrupt::ReceiveDataFull);
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}
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else
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{
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tape_.set_data_register(*value);
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tape_.clear_interrupts(Interrupt::TransmitDataEmpty);
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}
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break;
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case 0xfe05:
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if(!isReadOperation(operation))
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{
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const uint8_t interruptDisable = (*value)&0xf0;
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if( interruptDisable )
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{
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if( interruptDisable&0x10 ) interrupt_status_ &= ~Interrupt::DisplayEnd;
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if( interruptDisable&0x20 ) interrupt_status_ &= ~Interrupt::RealTimeClock;
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if( interruptDisable&0x40 ) interrupt_status_ &= ~Interrupt::HighToneDetect;
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evaluate_interrupts();
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// TODO: NMI
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}
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// latch the paged ROM in case external hardware is being emulated
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active_rom_ = (Electron::ROMSlot)(*value & 0xf);
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// apply the ULA's test
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if(*value & 0x08)
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{
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if(*value & 0x04)
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{
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keyboard_is_active_ = false;
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basic_is_active_ = false;
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}
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else
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{
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keyboard_is_active_ = !(*value & 0x02);
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basic_is_active_ = !keyboard_is_active_;
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}
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}
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}
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break;
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case 0xfe06:
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if(!isReadOperation(operation))
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{
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update_audio();
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speaker_->set_divider(*value);
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tape_.set_counter(*value);
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}
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break;
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case 0xfe07:
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if(!isReadOperation(operation))
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{
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// update screen mode
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uint8_t new_screen_mode = ((*value) >> 3)&7;
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if(new_screen_mode == 7) new_screen_mode = 4;
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if(new_screen_mode != screen_mode_)
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{
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update_display();
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screen_mode_ = new_screen_mode;
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switch(screen_mode_)
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{
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case 0: case 1: case 2: screen_mode_base_address_ = 0x3000; break;
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case 3: screen_mode_base_address_ = 0x4000; break;
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case 4: case 5: screen_mode_base_address_ = 0x5800; break;
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case 6: screen_mode_base_address_ = 0x6000; break;
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}
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}
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// update speaker mode
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bool new_speaker_is_enabled = (*value & 6) == 2;
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if(new_speaker_is_enabled != speaker_is_enabled_)
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{
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update_audio();
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speaker_->set_is_enabled(new_speaker_is_enabled);
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speaker_is_enabled_ = new_speaker_is_enabled;
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}
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tape_.set_is_enabled((*value & 6) != 6);
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tape_.set_is_in_input_mode((*value & 6) == 0);
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tape_.set_is_running(((*value)&0x40) ? true : false);
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// TODO: caps lock LED
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}
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break;
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case 0xfe08: case 0xfe09: case 0xfe0a: case 0xfe0b: case 0xfe0c: case 0xfe0d: case 0xfe0e: case 0xfe0f:
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{
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if(!isReadOperation(operation))
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{
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update_display();
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static const int registers[4][4] = {
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{10, 8, 2, 0},
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{14, 12, 6, 4},
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{15, 13, 7, 5},
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{11, 9, 3, 1},
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};
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const int index = (address >> 1)&3;
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const uint8_t colour = ~(*value);
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if(address&1)
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{
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palette_[registers[index][0]] = (palette_[registers[index][0]]&3) | ((colour >> 1)&4);
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palette_[registers[index][1]] = (palette_[registers[index][1]]&3) | ((colour >> 0)&4);
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palette_[registers[index][2]] = (palette_[registers[index][2]]&3) | ((colour << 1)&4);
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palette_[registers[index][3]] = (palette_[registers[index][3]]&3) | ((colour << 2)&4);
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palette_[registers[index][2]] = (palette_[registers[index][2]]&5) | ((colour >> 4)&2);
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palette_[registers[index][3]] = (palette_[registers[index][3]]&5) | ((colour >> 3)&2);
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}
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else
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{
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palette_[registers[index][0]] = (palette_[registers[index][0]]&6) | ((colour >> 7)&1);
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palette_[registers[index][1]] = (palette_[registers[index][1]]&6) | ((colour >> 6)&1);
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palette_[registers[index][2]] = (palette_[registers[index][2]]&6) | ((colour >> 5)&1);
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palette_[registers[index][3]] = (palette_[registers[index][3]]&6) | ((colour >> 4)&1);
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palette_[registers[index][0]] = (palette_[registers[index][0]]&5) | ((colour >> 2)&2);
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palette_[registers[index][1]] = (palette_[registers[index][1]]&5) | ((colour >> 1)&2);
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}
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// regenerate all palette tables for now
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#define pack(a, b) (uint8_t)((a << 4) | (b))
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for(int byte = 0; byte < 256; byte++)
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{
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uint8_t *target = (uint8_t *)&palette_tables_.forty1bpp[byte];
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target[0] = pack(palette_[(byte&0x80) >> 4], palette_[(byte&0x40) >> 3]);
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target[1] = pack(palette_[(byte&0x20) >> 2], palette_[(byte&0x10) >> 1]);
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target = (uint8_t *)&palette_tables_.eighty2bpp[byte];
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target[0] = pack(palette_[((byte&0x80) >> 4) | ((byte&0x08) >> 2)], palette_[((byte&0x40) >> 3) | ((byte&0x04) >> 1)]);
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target[1] = pack(palette_[((byte&0x20) >> 2) | ((byte&0x02) >> 0)], palette_[((byte&0x10) >> 1) | ((byte&0x01) << 1)]);
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target = (uint8_t *)&palette_tables_.eighty1bpp[byte];
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target[0] = pack(palette_[(byte&0x80) >> 4], palette_[(byte&0x40) >> 3]);
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target[1] = pack(palette_[(byte&0x20) >> 2], palette_[(byte&0x10) >> 1]);
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target[2] = pack(palette_[(byte&0x08) >> 0], palette_[(byte&0x04) << 1]);
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target[3] = pack(palette_[(byte&0x02) << 2], palette_[(byte&0x01) << 3]);
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palette_tables_.forty2bpp[byte] = pack(palette_[((byte&0x80) >> 4) | ((byte&0x08) >> 2)], palette_[((byte&0x40) >> 3) | ((byte&0x04) >> 1)]);
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palette_tables_.eighty4bpp[byte] = pack( palette_[((byte&0x80) >> 4) | ((byte&0x20) >> 3) | ((byte&0x08) >> 2) | ((byte&0x02) >> 1)],
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palette_[((byte&0x40) >> 3) | ((byte&0x10) >> 2) | ((byte&0x04) >> 1) | ((byte&0x01) >> 0)]);
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}
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#undef pack
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}
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}
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break;
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case 0xfc04: case 0xfc05: case 0xfc06: case 0xfc07:
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if(plus3_ && (address&0x00f0) == 0x00c0)
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{
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if(is_holding_shift_ && address == 0xfcc4)
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{
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is_holding_shift_ = false;
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set_key_state(KeyShift, false);
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}
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if(isReadOperation(operation))
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*value = plus3_->get_register(address);
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else
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plus3_->set_register(address, *value);
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}
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break;
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case 0xfc00:
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if(plus3_ && (address&0x00f0) == 0x00c0)
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{
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if(!isReadOperation(operation))
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{
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plus3_->set_control_register(*value);
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}
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else
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*value = 1;
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}
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break;
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default:
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if(address >= 0xc000)
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{
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if(isReadOperation(operation))
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{
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if(
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use_fast_tape_hack_ &&
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tape_.has_tape() &&
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(operation == CPU6502::BusOperation::ReadOpcode) &&
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(
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(address == 0xf4e5) || (address == 0xf4e6) || // double NOPs at 0xf4e5, 0xf6de, 0xf6fa and 0xfa51
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(address == 0xf6de) || (address == 0xf6df) || // act to disable the normal branch into tape-handling
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(address == 0xf6fa) || (address == 0xf6fb) || // code, forcing the OS along the serially-accessed ROM
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(address == 0xfa51) || (address == 0xfa52) || // pathway.
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(address == 0xf0a8) // 0xf0a8 is from where a service call would normally be
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// dispatched; we can check whether it would be call 14
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// (i.e. read byte) and, if so, whether the OS was about to
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// issue a read byte call to a ROM despite being the tape
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// FS being selected. If so then this is a get byte that
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// we should service synthetically. Put the byte into Y
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// and set A to zero to report that action was taken, then
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// allow the PC read to return an RTS.
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)
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)
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{
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uint8_t service_call = (uint8_t)get_value_of_register(CPU6502::Register::X);
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if(address == 0xf0a8)
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{
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if(!ram_[0x247] && service_call == 14)
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{
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tape_.set_delegate(nullptr);
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// TODO: handle tape wrap around.
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int cycles_left_while_plausibly_in_data = 50;
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tape_.clear_interrupts(Interrupt::ReceiveDataFull);
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while(!tape_.get_tape()->is_at_end())
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{
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tape_.run_for_input_pulse();
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cycles_left_while_plausibly_in_data--;
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if(!cycles_left_while_plausibly_in_data) fast_load_is_in_data_ = false;
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if( (tape_.get_interrupt_status() & Interrupt::ReceiveDataFull) &&
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(fast_load_is_in_data_ || tape_.get_data_register() == 0x2a)
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) break;
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}
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tape_.set_delegate(this);
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tape_.clear_interrupts(Interrupt::ReceiveDataFull);
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interrupt_status_ |= tape_.get_interrupt_status();
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fast_load_is_in_data_ = true;
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set_value_of_register(CPU6502::Register::A, 0);
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set_value_of_register(CPU6502::Register::Y, tape_.get_data_register());
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*value = 0x60; // 0x60 is RTS
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}
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else
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*value = os_[address & 16383];
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}
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else
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*value = 0xea;
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}
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else
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{
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*value = os_[address & 16383];
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}
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}
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}
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else
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{
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if(isReadOperation(operation))
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{
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*value = roms_[active_rom_][address & 16383];
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if(keyboard_is_active_)
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{
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*value &= 0xf0;
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for(int address_line = 0; address_line < 14; address_line++)
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{
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if(!(address&(1 << address_line))) *value |= key_states_[address_line];
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}
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}
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if(basic_is_active_)
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{
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*value &= roms_[ROMSlotBASIC][address & 16383];
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}
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} else if(rom_write_masks_[active_rom_])
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{
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roms_[active_rom_][address & 16383] = *value;
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}
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}
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break;
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}
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}
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// if(operation == CPU6502::BusOperation::ReadOpcode)
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// {
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// printf("%04x: %02x (%d)\n", address, *value, _fieldCycles);
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// }
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// const int end_of_field =
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// if(frame_cycles_ < (256 + first_graphics_line) << 7))
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const unsigned int pixel_line_clock = frame_cycles_;// + 128 - first_graphics_cycle + 80;
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const unsigned int line_before_cycle = graphics_line(pixel_line_clock);
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const unsigned int line_after_cycle = graphics_line(pixel_line_clock + cycles);
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// implicit assumption here: the number of 2Mhz cycles this bus operation will take
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// is never longer than a line. On the Electron, it's a safe one.
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if(line_before_cycle != line_after_cycle)
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{
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switch(line_before_cycle)
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{
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// case real_time_clock_interrupt_line: signal_interrupt(Interrupt::RealTimeClock); break;
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// case real_time_clock_interrupt_line+1: clear_interrupt(Interrupt::RealTimeClock); break;
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case display_end_interrupt_line: signal_interrupt(Interrupt::DisplayEnd); break;
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// case display_end_interrupt_line+1: clear_interrupt(Interrupt::DisplayEnd); break;
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}
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}
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if(
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(pixel_line_clock < real_time_clock_interrupt_1 && pixel_line_clock + cycles >= real_time_clock_interrupt_1) ||
|
|
(pixel_line_clock < real_time_clock_interrupt_2 && pixel_line_clock + cycles >= real_time_clock_interrupt_2))
|
|
{
|
|
signal_interrupt(Interrupt::RealTimeClock);
|
|
}
|
|
|
|
frame_cycles_ += cycles;
|
|
|
|
if(!(frame_cycles_&127)) phase_ += 64;
|
|
|
|
// deal with frame wraparound by updating the two dependent subsystems
|
|
// as though the exact end of frame had been hit, then reset those
|
|
// and allow the frame cycle counter to assume its real value
|
|
if(frame_cycles_ >= cycles_per_frame)
|
|
{
|
|
unsigned int nextFrameCycles = frame_cycles_ - cycles_per_frame;
|
|
frame_cycles_ = cycles_per_frame;
|
|
update_display();
|
|
update_audio();
|
|
display_output_position_ = 0;
|
|
audio_output_position_ = 0;
|
|
frame_cycles_ = nextFrameCycles;
|
|
}
|
|
|
|
if(!(frame_cycles_&16383))
|
|
update_audio();
|
|
tape_.run_for_cycles(cycles);
|
|
|
|
if(typer_) typer_->update((int)cycles);
|
|
if(plus3_) plus3_->run_for_cycles(4*cycles);
|
|
|
|
return cycles;
|
|
}
|
|
|
|
void Machine::synchronise()
|
|
{
|
|
update_display();
|
|
update_audio();
|
|
speaker_->flush();
|
|
}
|
|
|
|
void Machine::configure_as_target(const StaticAnalyser::Target &target)
|
|
{
|
|
if(target.tapes.size())
|
|
{
|
|
tape_.set_tape(target.tapes.front());
|
|
}
|
|
|
|
if(target.disks.size())
|
|
{
|
|
plus3_.reset(new Plus3);
|
|
|
|
if(target.acorn.has_dfs)
|
|
{
|
|
set_rom(ROMSlot0, dfs_, true);
|
|
}
|
|
if(target.acorn.has_adfs)
|
|
{
|
|
set_rom(ROMSlot4, adfs_, true);
|
|
set_rom(ROMSlot5, std::vector<uint8_t>(adfs_.begin() + 16384, adfs_.end()), true);
|
|
}
|
|
|
|
plus3_->set_disk(target.disks.front(), 0);
|
|
}
|
|
|
|
ROMSlot slot = ROMSlot12;
|
|
for(std::shared_ptr<Storage::Cartridge::Cartridge> cartridge : target.cartridges)
|
|
{
|
|
set_rom(slot, cartridge->get_segments().front().data, false);
|
|
slot = (ROMSlot)(((int)slot + 1)&15);
|
|
}
|
|
|
|
if(target.loadingCommand.length()) // TODO: and automatic loading option enabled
|
|
{
|
|
set_typer_for_string(target.loadingCommand.c_str());
|
|
}
|
|
if(target.acorn.should_hold_shift)
|
|
{
|
|
set_key_state(KeyShift, true);
|
|
is_holding_shift_ = true;
|
|
}
|
|
}
|
|
|
|
void Machine::set_rom(ROMSlot slot, std::vector<uint8_t> data, bool is_writeable)
|
|
{
|
|
uint8_t *target = nullptr;
|
|
switch(slot)
|
|
{
|
|
case ROMSlotDFS: dfs_ = data; return;
|
|
case ROMSlotADFS: adfs_ = data; return;
|
|
|
|
case ROMSlotOS: target = os_; break;
|
|
default:
|
|
target = roms_[slot];
|
|
rom_write_masks_[slot] = is_writeable;
|
|
break;
|
|
}
|
|
|
|
memcpy(target, &data[0], std::min((size_t)16384, data.size()));
|
|
}
|
|
|
|
inline void Machine::signal_interrupt(Electron::Interrupt interrupt)
|
|
{
|
|
interrupt_status_ |= interrupt;
|
|
evaluate_interrupts();
|
|
}
|
|
|
|
inline void Machine::clear_interrupt(Electron::Interrupt interrupt)
|
|
{
|
|
interrupt_status_ &= ~interrupt;
|
|
evaluate_interrupts();
|
|
}
|
|
|
|
void Machine::tape_did_change_interrupt_status(Tape *tape)
|
|
{
|
|
interrupt_status_ = (interrupt_status_ & ~(Interrupt::TransmitDataEmpty | Interrupt::ReceiveDataFull | Interrupt::HighToneDetect)) | tape_.get_interrupt_status();
|
|
evaluate_interrupts();
|
|
}
|
|
|
|
inline void Machine::evaluate_interrupts()
|
|
{
|
|
if(interrupt_status_ & interrupt_control_)
|
|
{
|
|
interrupt_status_ |= 1;
|
|
}
|
|
else
|
|
{
|
|
interrupt_status_ &= ~1;
|
|
}
|
|
set_irq_line(interrupt_status_ & 1);
|
|
}
|
|
|
|
inline void Machine::update_audio()
|
|
{
|
|
unsigned int difference = frame_cycles_ - audio_output_position_ + audio_output_position_error_;
|
|
audio_output_position_ = frame_cycles_;
|
|
speaker_->run_for_cycles(difference / Speaker::clock_rate_divider);
|
|
audio_output_position_error_ = difference % Speaker::clock_rate_divider;
|
|
}
|
|
|
|
inline void Machine::start_pixel_line()
|
|
{
|
|
current_pixel_line_ = (current_pixel_line_+1)&255;
|
|
if(!current_pixel_line_)
|
|
{
|
|
start_line_address_ = start_screen_address_;
|
|
current_character_row_ = 0;
|
|
is_blank_line_ = false;
|
|
}
|
|
else
|
|
{
|
|
bool mode_has_blank_lines = (screen_mode_ == 6) || (screen_mode_ == 3);
|
|
is_blank_line_ = (mode_has_blank_lines && ((current_character_row_ > 7 && current_character_row_ < 10) || (current_pixel_line_ > 249)));
|
|
|
|
if(!is_blank_line_)
|
|
{
|
|
start_line_address_++;
|
|
|
|
if(current_character_row_ > 7)
|
|
{
|
|
start_line_address_ += ((screen_mode_ < 4) ? 80 : 40) * 8 - 8;
|
|
current_character_row_ = 0;
|
|
}
|
|
}
|
|
}
|
|
current_screen_address_ = start_line_address_;
|
|
current_pixel_column_ = 0;
|
|
initial_output_target_ = current_output_target_ = nullptr;
|
|
}
|
|
|
|
inline void Machine::end_pixel_line()
|
|
{
|
|
if(current_output_target_) crt_->output_data((unsigned int)((current_output_target_ - initial_output_target_) * current_output_divider_), current_output_divider_);
|
|
current_character_row_++;
|
|
}
|
|
|
|
inline void Machine::output_pixels(unsigned int number_of_cycles)
|
|
{
|
|
if(!number_of_cycles) return;
|
|
|
|
if(is_blank_line_)
|
|
{
|
|
crt_->output_blank(number_of_cycles * crt_cycles_multiplier);
|
|
}
|
|
else
|
|
{
|
|
unsigned int divider = 0;
|
|
switch(screen_mode_)
|
|
{
|
|
case 0: case 3: divider = 2; break;
|
|
case 1: case 4: case 6: divider = 4; break;
|
|
case 2: case 5: divider = 8; break;
|
|
}
|
|
|
|
if(!initial_output_target_ || divider != current_output_divider_)
|
|
{
|
|
if(current_output_target_) crt_->output_data((unsigned int)((current_output_target_ - initial_output_target_) * current_output_divider_), current_output_divider_);
|
|
current_output_divider_ = divider;
|
|
initial_output_target_ = current_output_target_ = crt_->allocate_write_area(640 / current_output_divider_);
|
|
}
|
|
|
|
#define get_pixel() \
|
|
if(current_screen_address_&32768)\
|
|
{\
|
|
current_screen_address_ = (screen_mode_base_address_ + current_screen_address_)&32767;\
|
|
}\
|
|
last_pixel_byte_ = ram_[current_screen_address_];\
|
|
current_screen_address_ = current_screen_address_+8
|
|
|
|
switch(screen_mode_)
|
|
{
|
|
case 0: case 3:
|
|
if(initial_output_target_)
|
|
{
|
|
while(number_of_cycles--)
|
|
{
|
|
get_pixel();
|
|
*(uint32_t *)current_output_target_ = palette_tables_.eighty1bpp[last_pixel_byte_];
|
|
current_output_target_ += 4;
|
|
current_pixel_column_++;
|
|
}
|
|
} else current_output_target_ += 4*number_of_cycles;
|
|
break;
|
|
|
|
case 1:
|
|
if(initial_output_target_)
|
|
{
|
|
while(number_of_cycles--)
|
|
{
|
|
get_pixel();
|
|
*(uint16_t *)current_output_target_ = palette_tables_.eighty2bpp[last_pixel_byte_];
|
|
current_output_target_ += 2;
|
|
current_pixel_column_++;
|
|
}
|
|
} else current_output_target_ += 2*number_of_cycles;
|
|
break;
|
|
|
|
case 2:
|
|
if(initial_output_target_)
|
|
{
|
|
while(number_of_cycles--)
|
|
{
|
|
get_pixel();
|
|
*current_output_target_ = palette_tables_.eighty4bpp[last_pixel_byte_];
|
|
current_output_target_ += 1;
|
|
current_pixel_column_++;
|
|
}
|
|
} else current_output_target_ += number_of_cycles;
|
|
break;
|
|
|
|
case 4: case 6:
|
|
if(initial_output_target_)
|
|
{
|
|
if(current_pixel_column_&1)
|
|
{
|
|
last_pixel_byte_ <<= 4;
|
|
*(uint16_t *)current_output_target_ = palette_tables_.forty1bpp[last_pixel_byte_];
|
|
current_output_target_ += 2;
|
|
|
|
number_of_cycles--;
|
|
current_pixel_column_++;
|
|
}
|
|
while(number_of_cycles > 1)
|
|
{
|
|
get_pixel();
|
|
*(uint16_t *)current_output_target_ = palette_tables_.forty1bpp[last_pixel_byte_];
|
|
current_output_target_ += 2;
|
|
|
|
last_pixel_byte_ <<= 4;
|
|
*(uint16_t *)current_output_target_ = palette_tables_.forty1bpp[last_pixel_byte_];
|
|
current_output_target_ += 2;
|
|
|
|
number_of_cycles -= 2;
|
|
current_pixel_column_+=2;
|
|
}
|
|
if(number_of_cycles)
|
|
{
|
|
get_pixel();
|
|
*(uint16_t *)current_output_target_ = palette_tables_.forty1bpp[last_pixel_byte_];
|
|
current_output_target_ += 2;
|
|
current_pixel_column_++;
|
|
}
|
|
} else current_output_target_ += 2 * number_of_cycles;
|
|
break;
|
|
|
|
case 5:
|
|
if(initial_output_target_)
|
|
{
|
|
if(current_pixel_column_&1)
|
|
{
|
|
last_pixel_byte_ <<= 2;
|
|
*current_output_target_ = palette_tables_.forty2bpp[last_pixel_byte_];
|
|
current_output_target_ += 1;
|
|
|
|
number_of_cycles--;
|
|
current_pixel_column_++;
|
|
}
|
|
while(number_of_cycles > 1)
|
|
{
|
|
get_pixel();
|
|
*current_output_target_ = palette_tables_.forty2bpp[last_pixel_byte_];
|
|
current_output_target_ += 1;
|
|
|
|
last_pixel_byte_ <<= 2;
|
|
*current_output_target_ = palette_tables_.forty2bpp[last_pixel_byte_];
|
|
current_output_target_ += 1;
|
|
|
|
number_of_cycles -= 2;
|
|
current_pixel_column_+=2;
|
|
}
|
|
if(number_of_cycles)
|
|
{
|
|
get_pixel();
|
|
*current_output_target_ = palette_tables_.forty2bpp[last_pixel_byte_];
|
|
current_output_target_ += 1;
|
|
current_pixel_column_++;
|
|
}
|
|
} else current_output_target_ += number_of_cycles;
|
|
break;
|
|
}
|
|
|
|
#undef get_pixel
|
|
}
|
|
}
|
|
|
|
inline void Machine::update_display()
|
|
{
|
|
/*
|
|
|
|
Odd field: Even field:
|
|
|
|
|--S--| -S-|
|
|
|--S--| |--S--|
|
|
|-S-B-| = 3 |--S--| = 2.5
|
|
|--B--| |--B--|
|
|
|--P--| |--P--|
|
|
|--B--| = 312 |--B--| = 312.5
|
|
|-B-
|
|
|
|
*/
|
|
|
|
int final_line = frame_cycles_ >> 7;
|
|
while(display_output_position_ < frame_cycles_)
|
|
{
|
|
int line = display_output_position_ >> 7;
|
|
|
|
// Priority one: sync.
|
|
// ===================
|
|
|
|
// full sync lines are 0, 1, field_divider_line+1 and field_divider_line+2
|
|
if(line == 0 || line == 1 || line == field_divider_line+1 || line == field_divider_line+2)
|
|
{
|
|
// wait for the line to complete before signalling
|
|
if(final_line == line) return;
|
|
crt_->output_sync(128 * crt_cycles_multiplier);
|
|
display_output_position_ += 128;
|
|
continue;
|
|
}
|
|
|
|
// line 2 is a left-sync line
|
|
if(line == 2)
|
|
{
|
|
// wait for the line to complete before signalling
|
|
if(final_line == line) return;
|
|
crt_->output_sync(64 * crt_cycles_multiplier);
|
|
crt_->output_blank(64 * crt_cycles_multiplier);
|
|
display_output_position_ += 128;
|
|
continue;
|
|
}
|
|
|
|
// line field_divider_line is a right-sync line
|
|
if(line == field_divider_line)
|
|
{
|
|
// wait for the line to complete before signalling
|
|
if(final_line == line) return;
|
|
crt_->output_sync(9 * crt_cycles_multiplier);
|
|
crt_->output_blank(55 * crt_cycles_multiplier);
|
|
crt_->output_sync(64 * crt_cycles_multiplier);
|
|
display_output_position_ += 128;
|
|
continue;
|
|
}
|
|
|
|
// Priority two: blank lines.
|
|
// ==========================
|
|
//
|
|
// Given that it is not a sync line, this is a blank line if it is less than first_graphics_line, or greater
|
|
// than first_graphics_line+255 and less than first_graphics_line+field_divider_line, or greater than
|
|
// first_graphics_line+field_divider_line+255 (TODO: or this is Mode 3 or 6 and this should be blank)
|
|
if(
|
|
line < first_graphics_line ||
|
|
(line > first_graphics_line+255 && line < first_graphics_line+field_divider_line) ||
|
|
line > first_graphics_line+field_divider_line+255)
|
|
{
|
|
if(final_line == line) return;
|
|
crt_->output_sync(9 * crt_cycles_multiplier);
|
|
crt_->output_blank(119 * crt_cycles_multiplier);
|
|
display_output_position_ += 128;
|
|
continue;
|
|
}
|
|
|
|
// Final possibility: this is a pixel line.
|
|
// ========================================
|
|
|
|
// determine how far we're going from left to right
|
|
unsigned int this_cycle = display_output_position_&127;
|
|
unsigned int final_cycle = frame_cycles_&127;
|
|
if(final_line > line)
|
|
{
|
|
final_cycle = 128;
|
|
}
|
|
|
|
// output format is:
|
|
// 9 cycles: sync
|
|
// ... to 24 cycles: colour burst
|
|
// ... to first_graphics_cycle: blank
|
|
// ... for 80 cycles: pixels
|
|
// ... until end of line: blank
|
|
while(this_cycle < final_cycle)
|
|
{
|
|
if(this_cycle < 9)
|
|
{
|
|
if(final_cycle < 9) return;
|
|
crt_->output_sync(9 * crt_cycles_multiplier);
|
|
display_output_position_ += 9;
|
|
this_cycle = 9;
|
|
}
|
|
|
|
if(this_cycle < 24)
|
|
{
|
|
if(final_cycle < 24) return;
|
|
crt_->output_colour_burst((24-9) * crt_cycles_multiplier, phase_, 12);
|
|
display_output_position_ += 24-9;
|
|
this_cycle = 24;
|
|
// TODO: phase shouldn't be zero on every line
|
|
}
|
|
|
|
if(this_cycle < first_graphics_cycle)
|
|
{
|
|
if(final_cycle < first_graphics_cycle) return;
|
|
crt_->output_blank((first_graphics_cycle - 24) * crt_cycles_multiplier);
|
|
display_output_position_ += first_graphics_cycle - 24;
|
|
this_cycle = first_graphics_cycle;
|
|
start_pixel_line();
|
|
}
|
|
|
|
if(this_cycle < first_graphics_cycle + 80)
|
|
{
|
|
unsigned int length_to_output = std::min(final_cycle, (first_graphics_cycle + 80)) - this_cycle;
|
|
output_pixels(length_to_output);
|
|
display_output_position_ += length_to_output;
|
|
this_cycle += length_to_output;
|
|
}
|
|
|
|
if(this_cycle >= first_graphics_cycle + 80)
|
|
{
|
|
if(final_cycle < 128) return;
|
|
end_pixel_line();
|
|
crt_->output_blank((128 - (first_graphics_cycle + 80)) * crt_cycles_multiplier);
|
|
display_output_position_ += 128 - (first_graphics_cycle + 80);
|
|
this_cycle = 128;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void Machine::clear_all_keys()
|
|
{
|
|
memset(key_states_, 0, sizeof(key_states_));
|
|
}
|
|
|
|
void Machine::set_key_state(uint16_t key, bool isPressed)
|
|
{
|
|
if(key == KeyBreak)
|
|
{
|
|
set_reset_line(isPressed);
|
|
}
|
|
else
|
|
{
|
|
if(isPressed)
|
|
key_states_[key >> 4] |= key&0xf;
|
|
else
|
|
key_states_[key >> 4] &= ~(key&0xf);
|
|
}
|
|
}
|