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CLK/Machines/Oric/Microdisc.cpp

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//
// Microdisc.cpp
// Clock Signal
//
// Created by Thomas Harte on 22/11/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#include "Microdisc.hpp"
using namespace Oric;
Microdisc::Microdisc() :
irq_enable_(false),
delegate_(nullptr),
paging_flags_(BASICDisable),
WD1770(P1773)
{}
void Microdisc::set_disk(std::shared_ptr<Storage::Disk::Disk> disk, int drive)
{
if(!drives_[drive])
{
drives_[drive].reset(new Storage::Disk::Drive);
if(drive == selected_drive_) set_drive(drives_[drive]);
}
drives_[drive]->set_disk(disk);
}
void Microdisc::set_control_register(uint8_t control)
{
// b2: data separator clock rate select (1 = double) [TODO]
// b65: drive select
selected_drive_ = (control >> 5)&3;
set_drive(drives_[selected_drive_]);
// b4: side select
for(int c = 0; c < 4; c++)
{
if(drives_[c]) drives_[c]->set_head((control & 0x10) ? 1 : 0);
}
// b3: double density select (0 = double)
set_is_double_density(!(control & 0x08));
// b0: IRQ enable
bool had_irq = get_interrupt_request_line();
irq_enable_ = !!(control & 0x01);
bool has_irq = get_interrupt_request_line();
if(has_irq != had_irq && delegate_)
{
delegate_->wd1770_did_change_interrupt_request_status(this);
}
// b7: EPROM select (0 = select)
// b1: ROM disable (0 = disable)
int new_paging_flags = ((control & 0x02) ? 0 : BASICDisable) | ((control & 0x80) ? MicrodscDisable : 0);
if(new_paging_flags != paging_flags_)
{
paging_flags_ = new_paging_flags;
if(delegate_) delegate_->microdisc_did_change_paging_flags(this);
}
}
bool Microdisc::get_interrupt_request_line()
{
return irq_enable_ && WD1770::get_interrupt_request_line();
}
uint8_t Microdisc::get_interrupt_request_register()
{
return 0x7f | (get_interrupt_request_line() ? 0x00 : 0x80);
}
uint8_t Microdisc::get_data_request_register()
{
return 0x7f | (get_data_request_line() ? 0x00 : 0x80);
}