mirror of
https://github.com/TomHarte/CLK.git
synced 2024-11-23 03:32:32 +00:00
281 lines
9.0 KiB
C++
281 lines
9.0 KiB
C++
//
|
|
// Disk.cpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 18/09/2016.
|
|
// Copyright © 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#include "Disk.hpp"
|
|
#include "../../Storage/Disk/DiskController.hpp"
|
|
#include "../../Storage/Disk/Encodings/MFM.hpp"
|
|
#include "../../NumberTheory/CRC.hpp"
|
|
#include <algorithm>
|
|
|
|
using namespace StaticAnalyser::Acorn;
|
|
|
|
class FMParser: public Storage::Disk::Controller {
|
|
public:
|
|
std::shared_ptr<Storage::Disk::Drive> drive;
|
|
|
|
FMParser(bool is_mfm) :
|
|
Storage::Disk::Controller(4000000, 1, 300),
|
|
crc_generator_(0x1021, 0xffff),
|
|
shift_register_(0), track_(0), is_mfm_(is_mfm)
|
|
{
|
|
Storage::Time bit_length;
|
|
bit_length.length = 1;
|
|
bit_length.clock_rate = is_mfm ? 500000 : 250000; // i.e. 250 kbps (including clocks)
|
|
set_expected_bit_length(bit_length);
|
|
|
|
drive.reset(new Storage::Disk::Drive);
|
|
set_drive(drive);
|
|
set_motor_on(true);
|
|
}
|
|
|
|
/*!
|
|
Attempts to read the sector located at @c track and @c sector.
|
|
|
|
@returns a sector if one was found; @c nullptr otherwise.
|
|
*/
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> get_sector(uint8_t track, uint8_t sector)
|
|
{
|
|
int difference = (int)track - (int)track_;
|
|
track_ = track;
|
|
|
|
if(difference)
|
|
{
|
|
int direction = difference < 0 ? -1 : 1;
|
|
difference *= direction;
|
|
|
|
for(int c = 0; c < difference; c++) step(direction);
|
|
}
|
|
|
|
return get_sector(sector);
|
|
}
|
|
|
|
private:
|
|
unsigned int shift_register_;
|
|
int index_count_;
|
|
uint8_t track_;
|
|
int bit_count_;
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> sector_cache_[65536];
|
|
NumberTheory::CRC16 crc_generator_;
|
|
bool is_mfm_;
|
|
|
|
void process_input_bit(int value, unsigned int cycles_since_index_hole)
|
|
{
|
|
shift_register_ = ((shift_register_ << 1) | (unsigned int)value) & 0xffff;
|
|
bit_count_++;
|
|
}
|
|
|
|
void process_index_hole()
|
|
{
|
|
index_count_++;
|
|
}
|
|
|
|
uint8_t get_next_byte()
|
|
{
|
|
bit_count_ = 0;
|
|
while(bit_count_ < 16) run_for_cycles(1);
|
|
uint8_t byte = (uint8_t)(
|
|
((shift_register_&0x0001) >> 0) |
|
|
((shift_register_&0x0004) >> 1) |
|
|
((shift_register_&0x0010) >> 2) |
|
|
((shift_register_&0x0040) >> 3) |
|
|
((shift_register_&0x0100) >> 4) |
|
|
((shift_register_&0x0400) >> 5) |
|
|
((shift_register_&0x1000) >> 6) |
|
|
((shift_register_&0x4000) >> 7));
|
|
crc_generator_.add(byte);
|
|
return byte;
|
|
}
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> get_next_sector()
|
|
{
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> sector(new Storage::Encodings::MFM::Sector);
|
|
index_count_ = 0;
|
|
|
|
while(index_count_ < 2)
|
|
{
|
|
// look for an ID address mark
|
|
while(1)
|
|
{
|
|
run_for_cycles(1);
|
|
if(is_mfm_)
|
|
{
|
|
if(shift_register_ == Storage::Encodings::MFM::MFMAddressMark)
|
|
{
|
|
uint8_t mark = get_next_byte();
|
|
if(mark == Storage::Encodings::MFM::MFMIDAddressByte) break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if(shift_register_ == Storage::Encodings::MFM::FMIDAddressMark) break;
|
|
}
|
|
if(index_count_ >= 2) return nullptr;
|
|
}
|
|
|
|
crc_generator_.reset();
|
|
sector->track = get_next_byte();
|
|
sector->side = get_next_byte();
|
|
sector->sector = get_next_byte();
|
|
uint8_t size = get_next_byte();
|
|
uint16_t header_crc = crc_generator_.get_value();
|
|
if((header_crc >> 8) != get_next_byte()) continue;
|
|
if((header_crc & 0xff) != get_next_byte()) continue;
|
|
|
|
// look for data mark
|
|
while(1)
|
|
{
|
|
run_for_cycles(1);
|
|
if(is_mfm_)
|
|
{
|
|
if(shift_register_ == Storage::Encodings::MFM::MFMAddressMark)
|
|
{
|
|
uint8_t mark = get_next_byte();
|
|
if(mark == Storage::Encodings::MFM::MFMDataAddressByte) break;
|
|
if(mark == Storage::Encodings::MFM::MFMIDAddressByte) return nullptr;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if(shift_register_ == Storage::Encodings::MFM::FMDataAddressMark) break;
|
|
if(shift_register_ == Storage::Encodings::MFM::FMIDAddressMark) return nullptr;
|
|
}
|
|
if(index_count_ >= 2) return nullptr;
|
|
}
|
|
|
|
size_t data_size = (size_t)(128 << size);
|
|
sector->data.reserve(data_size);
|
|
crc_generator_.reset();
|
|
for(size_t c = 0; c < data_size; c++)
|
|
{
|
|
sector->data.push_back(get_next_byte());
|
|
}
|
|
uint16_t data_crc = crc_generator_.get_value();
|
|
if((data_crc >> 8) != get_next_byte()) continue;
|
|
if((data_crc & 0xff) != get_next_byte()) continue;
|
|
|
|
return sector;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> get_sector(uint8_t sector)
|
|
{
|
|
// uint16_t sector_address = (uint16_t)((track_ << 8) | sector);
|
|
// if(sector_cache_[sector_address]) return sector_cache_[sector_address];
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> first_sector = get_next_sector();
|
|
if(!first_sector) return first_sector;
|
|
if(first_sector->sector == sector) return first_sector;
|
|
|
|
while(1)
|
|
{
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> next_sector = get_next_sector();
|
|
if(next_sector->sector == first_sector->sector) return nullptr;
|
|
if(next_sector->sector == sector) return next_sector;
|
|
}
|
|
}
|
|
};
|
|
|
|
std::unique_ptr<Catalogue> StaticAnalyser::Acorn::GetDFSCatalogue(const std::shared_ptr<Storage::Disk::Disk> &disk)
|
|
{
|
|
// c.f. http://beebwiki.mdfs.net/Acorn_DFS_disc_format
|
|
std::unique_ptr<Catalogue> catalogue(new Catalogue);
|
|
FMParser parser(false);
|
|
parser.drive->set_disk(disk);
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> names = parser.get_sector(0, 0);
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> details = parser.get_sector(0, 1);
|
|
|
|
if(!names || !details) return nullptr;
|
|
if(names->data.size() != 256 || details->data.size() != 256) return nullptr;
|
|
|
|
uint8_t final_file_offset = details->data[5];
|
|
if(final_file_offset&7) return nullptr;
|
|
|
|
char disk_name[13];
|
|
snprintf(disk_name, 13, "%.8s%.4s", &names->data[0], &details->data[0]);
|
|
catalogue->name = disk_name;
|
|
|
|
switch((details->data[6] >> 4)&3)
|
|
{
|
|
case 0: catalogue->bootOption = Catalogue::BootOption::None; break;
|
|
case 1: catalogue->bootOption = Catalogue::BootOption::LoadBOOT; break;
|
|
case 2: catalogue->bootOption = Catalogue::BootOption::RunBOOT; break;
|
|
case 3: catalogue->bootOption = Catalogue::BootOption::ExecBOOT; break;
|
|
}
|
|
|
|
// DFS files are stored contiguously, and listed in descending order of distance from track 0.
|
|
// So iterating backwards implies the least amount of seeking.
|
|
for(size_t file_offset = final_file_offset - 8; file_offset > 0; file_offset -= 8)
|
|
{
|
|
File new_file;
|
|
char name[10];
|
|
snprintf(name, 10, "%c.%.7s", names->data[file_offset + 7] & 0x7f, &names->data[file_offset]);
|
|
new_file.name = name;
|
|
new_file.load_address = (uint32_t)(details->data[file_offset] | (details->data[file_offset+1] << 8) | ((details->data[file_offset+6]&0x0c) << 14));
|
|
new_file.execution_address = (uint32_t)(details->data[file_offset+2] | (details->data[file_offset+3] << 8) | ((details->data[file_offset+6]&0xc0) << 10));
|
|
new_file.is_protected = !!(names->data[file_offset + 7] & 0x80);
|
|
|
|
long data_length = (long)(details->data[file_offset+4] | (details->data[file_offset+5] << 8) | ((details->data[file_offset+6]&0x30) << 12));
|
|
int start_sector = details->data[file_offset+7] | ((details->data[file_offset+6]&0x03) << 8);
|
|
new_file.data.reserve((size_t)data_length);
|
|
|
|
if(start_sector < 2) continue;
|
|
while(data_length > 0)
|
|
{
|
|
uint8_t sector = (uint8_t)(start_sector % 10);
|
|
uint8_t track = (uint8_t)(start_sector / 10);
|
|
start_sector++;
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> next_sector = parser.get_sector(track, sector);
|
|
if(!next_sector) break;
|
|
|
|
long length_from_sector = std::min(data_length, 256l);
|
|
new_file.data.insert(new_file.data.end(), next_sector->data.begin(), next_sector->data.begin() + length_from_sector);
|
|
data_length -= length_from_sector;
|
|
}
|
|
if(!data_length) catalogue->files.push_front(new_file);
|
|
}
|
|
|
|
return catalogue;
|
|
}
|
|
std::unique_ptr<Catalogue> StaticAnalyser::Acorn::GetADFSCatalogue(const std::shared_ptr<Storage::Disk::Disk> &disk)
|
|
{
|
|
std::unique_ptr<Catalogue> catalogue(new Catalogue);
|
|
FMParser parser(true);
|
|
parser.drive->set_disk(disk);
|
|
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> free_space_map_second_half = parser.get_sector(0, 1);
|
|
if(!free_space_map_second_half) return nullptr;
|
|
|
|
std::vector<uint8_t> root_directory;
|
|
root_directory.reserve(5 * 256);
|
|
for(uint8_t c = 2; c < 7; c++)
|
|
{
|
|
std::shared_ptr<Storage::Encodings::MFM::Sector> sector = parser.get_sector(0, c);
|
|
if(!sector) return nullptr;
|
|
root_directory.insert(root_directory.end(), sector->data.begin(), sector->data.end());
|
|
}
|
|
|
|
// Quick sanity checks.
|
|
if(root_directory[0x4cb]) return nullptr;
|
|
if(root_directory[1] != 'H' || root_directory[2] != 'u' || root_directory[3] != 'g' || root_directory[4] != 'o') return nullptr;
|
|
if(root_directory[0x4FB] != 'H' || root_directory[0x4FC] != 'u' || root_directory[0x4FD] != 'g' || root_directory[0x4FE] != 'o') return nullptr;
|
|
|
|
switch(free_space_map_second_half->data[0xfd])
|
|
{
|
|
default: catalogue->bootOption = Catalogue::BootOption::None; break;
|
|
case 1: catalogue->bootOption = Catalogue::BootOption::LoadBOOT; break;
|
|
case 2: catalogue->bootOption = Catalogue::BootOption::RunBOOT; break;
|
|
case 3: catalogue->bootOption = Catalogue::BootOption::ExecBOOT; break;
|
|
}
|
|
|
|
return catalogue;
|
|
}
|