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CLK/Components/1770/1770.cpp

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//
// 1770.cpp
// Clock Signal
//
// Created by Thomas Harte on 17/09/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#include "1770.hpp"
#include "../../Storage/Disk/Encodings/MFM.hpp"
using namespace WD;
unsigned int counter = 0;
WD1770::Status::Status() :
type(Status::One),
write_protect(false),
record_type(false),
spin_up(false),
record_not_found(false),
crc_error(false),
seek_error(false),
lost_data(false),
data_request(false),
interrupt_request(false),
busy(false)
{}
WD1770::WD1770(Personality p) :
Storage::Disk::Controller(8000000, 16, 300),
interesting_event_mask_(Event::Command),
resume_point_(0),
delay_time_(0),
index_hole_count_target_(-1),
is_awaiting_marker_value_(false),
is_reading_data_(false),
delegate_(nullptr),
personality_(p),
head_is_loaded_(false)
{
set_is_double_density(false);
posit_event(Event::Command);
}
void WD1770::set_is_double_density(bool is_double_density)
{
is_double_density_ = is_double_density;
Storage::Time bit_length;
bit_length.length = 1;
bit_length.clock_rate = is_double_density ? 500000 : 250000;
set_expected_bit_length(bit_length);
if(!is_double_density) is_awaiting_marker_value_ = false;
}
void WD1770::set_register(int address, uint8_t value)
{
switch(address&3)
{
case 0:
{
if((value&0xf0) == 0xd0)
{
printf("!!!TODO: force interrupt!!!\n");
update_status([] (Status &status) {
status.type = Status::One;
});
}
else
{
command_ = value;
posit_event(Event::Command);
}
}
break;
case 1: track_ = value; break;
case 2: sector_ = value; break;
case 3:
data_ = value;
update_status([] (Status &status) {
status.data_request = false;
});
break;
}
}
uint8_t WD1770::get_register(int address)
{
switch(address&3)
{
default:
{
update_status([] (Status &status) {
status.interrupt_request = false;
});
uint8_t status =
(status_.write_protect ? Flag::WriteProtect : 0) |
(status_.crc_error ? Flag::CRCError : 0) |
(status_.busy ? Flag::Busy : 0);
switch(status_.type)
{
case Status::One:
status |=
(get_is_track_zero() ? Flag::TrackZero : 0) |
(status_.seek_error ? Flag::SeekError : 0);
// TODO: index hole
break;
case Status::Two:
case Status::Three:
status |=
(status_.record_type ? Flag::RecordType : 0) |
(status_.lost_data ? Flag::LostData : 0) |
(status_.data_request ? Flag::DataRequest : 0) |
(status_.record_not_found ? Flag::RecordNotFound : 0);
break;
}
if(!has_motor_on_line())
{
status |= get_drive_is_ready() ? 0 : Flag::NotReady;
if(status_.type == Status::One)
status |= (head_is_loaded_ ? Flag::HeadLoaded : 0);
}
else
{
status |= (get_motor_on() ? Flag::MotorOn : 0);
if(status_.type == Status::One)
status |= (status_.spin_up ? Flag::SpinUp : 0);
}
return status;
}
case 1: return track_;
case 2: return sector_;
case 3:
update_status([] (Status &status) {
status.data_request = false;
});
return data_;
}
}
void WD1770::run_for_cycles(unsigned int number_of_cycles)
{
counter += number_of_cycles;
Storage::Disk::Controller::run_for_cycles((int)number_of_cycles);
if(delay_time_)
{
if(delay_time_ <= number_of_cycles)
{
delay_time_ = 0;
posit_event(Event::Timer);
}
else
{
delay_time_ -= number_of_cycles;
}
}
}
void WD1770::process_input_bit(int value, unsigned int cycles_since_index_hole)
{
shift_register_ = (shift_register_ << 1) | value;
bits_since_token_++;
Token::Type token_type = Token::Byte;
if(!is_reading_data_)
{
if(!is_double_density_)
{
switch(shift_register_ & 0xffff)
{
case Storage::Encodings::MFM::FMIndexAddressMark:
token_type = Token::Index;
break;
case Storage::Encodings::MFM::FMIDAddressMark:
token_type = Token::ID;
break;
case Storage::Encodings::MFM::FMDataAddressMark:
token_type = Token::Data;
break;
case Storage::Encodings::MFM::FMDeletedDataAddressMark:
token_type = Token::DeletedData;
break;
default:
break;
}
}
else
{
switch(shift_register_ & 0xffff)
{
case Storage::Encodings::MFM::MFMIndexAddressMark:
bits_since_token_ = 0;
is_awaiting_marker_value_ = true;
return;
case Storage::Encodings::MFM::MFMAddressMark:
bits_since_token_ = 0;
is_awaiting_marker_value_ = true;
return;
default:
break;
}
}
if(token_type != Token::Byte)
{
latest_token_.type = token_type;
bits_since_token_ = 0;
posit_event(Event::Token);
return;
}
}
if(bits_since_token_ == 16)
{
latest_token_.type = Token::Byte;
latest_token_.byte_value = (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));
bits_since_token_ = 0;
if(is_awaiting_marker_value_ && is_double_density_)
{
is_awaiting_marker_value_ = false;
switch(latest_token_.byte_value)
{
case Storage::Encodings::MFM::MFMIndexAddressByte:
latest_token_.type = Token::Index;
break;
case Storage::Encodings::MFM::MFMIDAddressByte:
latest_token_.type = Token::ID;
break;
case Storage::Encodings::MFM::MFMDataAddressByte:
latest_token_.type = Token::Data;
break;
case Storage::Encodings::MFM::MFMDeletedDataAddressByte:
latest_token_.type = Token::DeletedData;
break;
default: break;
}
}
posit_event(Event::Token);
return;
}
}
void WD1770::process_index_hole()
{
index_hole_count_++;
posit_event(Event::IndexHole);
if(index_hole_count_target_ == index_hole_count_)
{
posit_event(Event::IndexHoleTarget);
index_hole_count_target_ = -1;
}
// motor power-down
if(index_hole_count_ == 9 && !status_.busy && has_motor_on_line())
{
set_motor_on(false);
}
// head unload
if(index_hole_count_ == 15 && !status_.busy && has_head_load_line())
{
set_head_load_request(false);
}
}
void WD1770::process_write_completed()
{
posit_event(Event::DataWritten);
}
// +------+----------+-------------------------+
// ! ! ! BITS !
// ! TYPE ! COMMAND ! 7 6 5 4 3 2 1 0 !
// +------+----------+-------------------------+
// ! 1 ! Restore ! 0 0 0 0 h v r1 r0 !
// ! 1 ! Seek ! 0 0 0 1 h v r1 r0 !
// ! 1 ! Step ! 0 0 1 u h v r1 r0 !
// ! 1 ! Step-in ! 0 1 0 u h v r1 r0 !
// ! 1 ! Step-out ! 0 1 1 u h v r1 r0 !
// ! 2 ! Rd sectr ! 1 0 0 m h E 0 0 !
// ! 2 ! Wt sectr ! 1 0 1 m h E P a0 !
// ! 3 ! Rd addr ! 1 1 0 0 h E 0 0 !
// ! 3 ! Rd track ! 1 1 1 0 h E 0 0 !
// ! 3 ! Wt track ! 1 1 1 1 h E P 0 !
// ! 4 ! Forc int ! 1 1 0 1 i3 i2 i1 i0 !
// +------+----------+-------------------------+
#define WAIT_FOR_EVENT(mask) resume_point_ = __LINE__; interesting_event_mask_ = mask; return; case __LINE__:
#define WAIT_FOR_TIME(ms) resume_point_ = __LINE__; interesting_event_mask_ = Event::Timer; delay_time_ = ms * 8000; if(delay_time_) return; case __LINE__:
#define WAIT_FOR_BYTES(count) resume_point_ = __LINE__; interesting_event_mask_ = Event::Token; distance_into_section_ = 0; return; case __LINE__: if(latest_token_.type == Token::Byte) distance_into_section_++; if(distance_into_section_ < count) { interesting_event_mask_ = Event::Token; return; }
#define BEGIN_SECTION() switch(resume_point_) { default:
#define END_SECTION() 0; }
#define READ_ID() \
if(new_event_type == Event::Token) \
{ \
if(!distance_into_section_ && latest_token_.type == Token::ID) {is_reading_data_ = true; distance_into_section_++; } \
else if(distance_into_section_ && distance_into_section_ < 7 && latest_token_.type == Token::Byte) \
{ \
header_[distance_into_section_ - 1] = latest_token_.byte_value; \
distance_into_section_++; \
} \
}
#define CONCATENATE(x, y) x ## y
#define INDIRECT_CONCATENATE(x, y) TOKENPASTE(x, y)
#define LINE_LABEL INDIRECT_CONCATENATE(label, __LINE__)
#define SPIN_UP() \
set_motor_on(true); \
index_hole_count_ = 0; \
index_hole_count_target_ = 6; \
WAIT_FOR_EVENT(Event::IndexHoleTarget); \
status_.spin_up = true;
void WD1770::posit_event(Event new_event_type)
{
if(!(interesting_event_mask_ & (int)new_event_type)) return;
interesting_event_mask_ &= ~new_event_type;
Status new_status;
BEGIN_SECTION()
// Wait for a new command, branch to the appropriate handler.
wait_for_command:
printf("Idle...\n");
is_reading_data_ = false;
index_hole_count_ = 0;
update_status([] (Status &status) {
status.busy = false;
status.interrupt_request = true;
});
WAIT_FOR_EVENT(Event::Command);
update_status([] (Status &status) {
status.busy = true;
status.interrupt_request = false;
});
printf("Starting %02x\n", command_);
if(!(command_ & 0x80)) goto begin_type_1;
if(!(command_ & 0x40)) goto begin_type_2;
goto begin_type_3;
/*
Type 1 entry point.
*/
begin_type_1:
// Set initial flags, skip spin-up if possible.
update_status([] (Status &status) {
status.type = Status::One;
status.seek_error = false;
status.crc_error = false;
status.data_request = false;
});
if(!has_motor_on_line() && !has_head_load_line()) goto test_type1_type;
if(has_motor_on_line()) goto begin_type1_spin_up;
goto begin_type1_load_head;
begin_type1_load_head:
if(!(command_&0x08))
{
set_head_load_request(false);
goto test_type1_type;
}
set_head_load_request(true);
if(head_is_loaded_) goto test_type1_type;
WAIT_FOR_EVENT(Event::HeadLoad);
goto test_type1_type;
begin_type1_spin_up:
if((command_&0x08) || get_motor_on()) goto test_type1_type;
SPIN_UP();
test_type1_type:
// Set step direction if this is a step in or out.
if((command_ >> 5) == 2) step_direction_ = 1;
if((command_ >> 5) == 3) step_direction_ = 0;
if((command_ >> 5) != 0) goto perform_step_command;
// This is now definitely either a seek or a restore; if it's a restore then set track to 0xff and data to 0x00.
if(!(command_ & 0x10))
{
track_ = 0xff;
data_ = 0;
}
perform_seek_or_restore_command:
if(track_ == data_) goto verify;
step_direction_ = (data_ > track_);
adjust_track:
if(step_direction_) track_++; else track_--;
perform_step:
if(!step_direction_ && get_is_track_zero())
{
track_ = 0;
goto verify;
}
step(step_direction_ ? 1 : -1);
int time_to_wait;
switch(command_ & 3)
{
default:
case 0: time_to_wait = 6; break;
case 1: time_to_wait = 12; break;
case 2: time_to_wait = (personality_ == P1772) ? 2 : 20; break;
case 3: time_to_wait = (personality_ == P1772) ? 3 : 30; break;
}
WAIT_FOR_TIME(time_to_wait);
if(command_ >> 5) goto verify;
goto perform_seek_or_restore_command;
perform_step_command:
if(command_ & 0x10) goto adjust_track;
goto perform_step;
verify:
if(!(command_ & 0x04))
{
goto wait_for_command;
}
index_hole_count_ = 0;
distance_into_section_ = 0;
verify_read_data:
WAIT_FOR_EVENT(Event::IndexHole | Event::Token);
READ_ID();
if(index_hole_count_ == 6)
{
update_status([] (Status &status) {
status.seek_error = true;
});
goto wait_for_command;
}
if(distance_into_section_ == 7)
{
is_reading_data_ = false;
// TODO: CRC check
if(header_[0] == track_)
{
printf("Reached track %d\n", track_);
update_status([] (Status &status) {
status.crc_error = false;
});
goto wait_for_command;
}
distance_into_section_ = 0;
}
goto verify_read_data;
/*
Type 2 entry point.
*/
begin_type_2:
update_status([] (Status &status) {
status.type = Status::Two;
status.lost_data = false;
status.record_not_found = false;
status.write_protect = false;
status.record_type = false;
status.data_request = false;
});
distance_into_section_ = 0;
if((command_&0x08) && has_motor_on_line()) goto test_type2_delay;
if(!has_motor_on_line() && !has_head_load_line()) goto test_type2_delay;
if(has_motor_on_line()) goto begin_type2_spin_up;
goto begin_type2_load_head;
begin_type2_load_head:
set_head_load_request(true);
if(head_is_loaded_) goto test_type2_delay;
WAIT_FOR_EVENT(Event::HeadLoad);
goto test_type2_delay;
begin_type2_spin_up:
if(get_motor_on()) goto test_type2_delay;
// Perform spin up.
SPIN_UP();
test_type2_delay:
index_hole_count_ = 0;
if(!(command_ & 0x04)) goto test_type2_write_protection;
WAIT_FOR_TIME(30);
test_type2_write_protection:
if(command_&0x20 && get_drive_is_read_only())
{
update_status([] (Status &status) {
status.write_protect = true;
});
goto wait_for_command;
}
type2_get_header:
WAIT_FOR_EVENT(Event::IndexHole | Event::Token);
READ_ID();
if(index_hole_count_ == 5)
{
printf("Failed to find sector %d\n", sector_);
update_status([] (Status &status) {
status.record_not_found = true;
});
goto wait_for_command;
}
if(distance_into_section_ == 7)
{
is_reading_data_ = false;
if(header_[0] == track_ && header_[2] == sector_ &&
(has_motor_on_line() || !(command_&0x02) || ((command_&0x08) >> 3) == header_[1]))
{
// TODO: test CRC
goto type2_read_or_write_data;
}
distance_into_section_ = 0;
}
goto type2_get_header;
type2_read_or_write_data:
if(command_&0x20) goto type2_write_data;
goto type2_read_data;
type2_read_data:
WAIT_FOR_EVENT(Event::Token);
// TODO: timeout
if(latest_token_.type == Token::Data || latest_token_.type == Token::DeletedData)
{
update_status([this] (Status &status) {
status.record_type = (latest_token_.type == Token::DeletedData);
});
distance_into_section_ = 0;
is_reading_data_ = true;
goto type2_read_byte;
}
goto type2_read_data;
type2_read_byte:
WAIT_FOR_EVENT(Event::Token);
if(latest_token_.type != Token::Byte) goto type2_read_byte;
data_ = latest_token_.byte_value;
update_status([] (Status &status) {
status.lost_data |= status.data_request;
status.data_request = true;
});
distance_into_section_++;
if(distance_into_section_ == 128 << header_[3])
{
distance_into_section_ = 0;
goto type2_check_crc;
}
goto type2_read_byte;
type2_check_crc:
WAIT_FOR_EVENT(Event::Token);
if(latest_token_.type != Token::Byte) goto type2_read_byte;
header_[distance_into_section_] = latest_token_.byte_value;
distance_into_section_++;
if(distance_into_section_ == 2)
{
// TODO: check CRC
if(command_ & 0x10)
{
sector_++;
goto test_type2_write_protection;
}
printf("Read sector %d\n", sector_);
goto wait_for_command;
}
goto type2_check_crc;
type2_write_data:
WAIT_FOR_BYTES(2);
update_status([] (Status &status) {
status.data_request = true;
});
WAIT_FOR_BYTES(9);
if(status_.data_request)
{
update_status([] (Status &status) {
status.lost_data = true;
});
goto wait_for_command;
}
WAIT_FOR_BYTES(1);
if(is_double_density_)
{
WAIT_FOR_BYTES(11);
}
begin_writing();
for(int c = 0; c < (is_double_density_ ? 12 : 6); c++)
{
// zero is encoded the same way in both FM and MFM
for(int b = 0; b < 16; b++)
write_bit(!(b&1));
}
// printf("%d\n", counter);
WAIT_FOR_EVENT(Event::DataWritten);
distance_into_section_ = 0;
type2_write_loop:
// TODO: real data
for(int b = 0; b < 16; b++)
write_bit(!(b&1));
update_status([] (Status &status) {
status.data_request = true;
});
WAIT_FOR_EVENT(Event::DataWritten);
distance_into_section_++;
if(distance_into_section_ == 128 << header_[3])
{
goto type2_write_crc;
}
if(status_.data_request)
{
update_status([] (Status &status) {
status.lost_data = true;
});
goto wait_for_command;
}
type2_write_crc:
// TODO: write CRC and FF
for(int b = 0; b < 48; b++)
write_bit(!(b&1));
WAIT_FOR_EVENT(Event::DataWritten);
end_writing();
if(command_ & 0x10)
{
sector_++;
goto test_type2_write_protection;
}
printf("Wrote sector %d\n", sector_);
goto wait_for_command;
begin_type_3:
update_status([] (Status &status) {
status.type = Status::Three;
});
printf("!!!TODO: type 3 commands!!!\n");
END_SECTION()
}
void WD1770::update_status(std::function<void(Status &)> updater)
{
if(delegate_)
{
Status old_status = status_;
updater(status_);
bool did_change =
(status_.busy != old_status.busy) ||
(status_.data_request != old_status.data_request);
if(did_change) delegate_->wd1770_did_change_output(this);
}
else updater(status_);
}
void WD1770::set_head_load_request(bool head_load) {}
void WD1770::set_head_loaded(bool head_loaded)
{
head_is_loaded_ = head_loaded;
if(head_loaded) posit_event(Event::HeadLoad);
}
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