mirror of
https://github.com/TomHarte/CLK.git
synced 2024-11-30 04:50:08 +00:00
114 lines
3.0 KiB
C++
114 lines
3.0 KiB
C++
//
|
|
// BD500.cpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 14/01/2020.
|
|
// Copyright © 2020 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#include "BD500.hpp"
|
|
|
|
using namespace Oric;
|
|
|
|
/*
|
|
Notes on the code below: the Byte Drive 500 isn't well documented; this implementation is based on
|
|
experimentation without access to real hardware as documented in http://forum.defence-force.org/viewtopic.php?f=25&t=2055
|
|
and with additional guidance from iss of Oricutron (amongst other things) elsewhere,
|
|
e.g. http://forum.defence-force.org/viewtopic.php?f=22&t=1698&start=105#p21468
|
|
*/
|
|
|
|
BD500::BD500() : DiskController(P1793, 9000000, Storage::Disk::Drive::ReadyType::ShugartModifiedRDY) {
|
|
disable_basic_rom_ = true;
|
|
select_paged_item();
|
|
set_is_double_density(true);
|
|
set_drive(1);
|
|
}
|
|
|
|
void BD500::write(int address, uint8_t value) {
|
|
access(address);
|
|
|
|
if(address >= 0x0320 && address <= 0x0323) {
|
|
// if(address == 0x320) printf("Command %02x\n", value);
|
|
WD::WD1770::write(address, value);
|
|
}
|
|
|
|
if(address == 0x031a) {
|
|
// Drive select; kudos to iss of Oricutron for figuring this one out;
|
|
// cf. http://forum.defence-force.org/viewtopic.php?f=25&p=21409#p21393
|
|
switch(value & 0xe0) {
|
|
default: set_drive(0); break;
|
|
case 0x20: set_drive(1); break;
|
|
case 0x40: set_drive(2); break;
|
|
case 0x80: set_drive(4); break;
|
|
case 0xc0: set_drive(8); break;
|
|
}
|
|
}
|
|
}
|
|
|
|
uint8_t BD500::read(int address) {
|
|
access(address);
|
|
|
|
switch(address) {
|
|
default: return 0xff;
|
|
|
|
case 0x0320: case 0x0321: case 0x0322: case 0x0323:
|
|
return WD::WD1770::read(address);
|
|
|
|
case 0x312: return (get_data_request_line() ? 0x80 : 0x00) | (get_interrupt_request_line() ? 0x40 : 0x00);
|
|
}
|
|
}
|
|
|
|
void BD500::access(int address) {
|
|
// Determine whether to perform a command.
|
|
switch(address) {
|
|
case 0x0320: case 0x0321: case 0x0322: case 0x0323: case 0x0312:
|
|
return;
|
|
|
|
case 0x311: disable_basic_rom_ = true; break;
|
|
case 0x313: enable_overlay_ram_ = false; break;
|
|
case 0x314: enable_overlay_ram_ = true; break;
|
|
case 0x317: disable_basic_rom_ = false; break;
|
|
|
|
default:
|
|
// printf("Switch %04x???\n", address);
|
|
break;
|
|
}
|
|
|
|
select_paged_item();
|
|
}
|
|
|
|
void BD500::set_head_load_request(bool head_load) {
|
|
// Turn all motors on or off; if off then unload the head instantly.
|
|
is_loading_head_ |= head_load;
|
|
for_all_drives([head_load] (Storage::Disk::Drive &drive, size_t) {
|
|
drive.set_motor_on(head_load);
|
|
});
|
|
if(!head_load) set_head_loaded(false);
|
|
}
|
|
|
|
void BD500::run_for(const Cycles cycles) {
|
|
// If a head load is in progress and the selected drive is now ready,
|
|
// declare head loaded.
|
|
if(is_loading_head_ && get_drive().get_is_ready()) {
|
|
set_head_loaded(true);
|
|
is_loading_head_ = false;
|
|
}
|
|
|
|
WD::WD1770::run_for(cycles);
|
|
}
|
|
|
|
void BD500::set_activity_observer(Activity::Observer *observer) {
|
|
observer_ = observer;
|
|
if(observer) {
|
|
observer->register_led("BD-500");
|
|
observer_->set_led_status("BD-500", get_head_loaded());
|
|
}
|
|
}
|
|
|
|
void BD500::set_head_loaded(bool loaded) {
|
|
WD::WD1770::set_head_loaded(loaded);
|
|
if(observer_) {
|
|
observer_->set_led_status("BD-500", loaded);
|
|
}
|
|
}
|