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Made an attempt at read track. Which means process_input_bit can't just swallow syncs any more; it now reports them as tokens of type ::Sync.

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This commit is contained in:
Thomas Harte 2017-01-01 20:39:19 -05:00
parent 4ad2d2bedd
commit f94f34f053
3 changed files with 58 additions and 20 deletions
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73
Components/1770/1770.cpp
View File

@ -165,9 +165,9 @@ 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(data_mode_ == DataMode::Scanning)
{
Token::Type token_type = Token::Byte;
if(!is_double_density_)
{
switch(shift_register_ & 0xffff)
@ -175,22 +175,22 @@ void WD1770::process_input_bit(int value, unsigned int cycles_since_index_hole)
case Storage::Encodings::MFM::FMIndexAddressMark:
token_type = Token::Index;
crc_generator_.reset();
crc_generator_.add(Storage::Encodings::MFM::IndexAddressByte);
crc_generator_.add(latest_token_.byte_value = Storage::Encodings::MFM::IndexAddressByte);
break;
case Storage::Encodings::MFM::FMIDAddressMark:
token_type = Token::ID;
crc_generator_.reset();
crc_generator_.add(Storage::Encodings::MFM::IDAddressByte);
crc_generator_.add(latest_token_.byte_value = Storage::Encodings::MFM::IDAddressByte);
break;
case Storage::Encodings::MFM::FMDataAddressMark:
token_type = Token::Data;
crc_generator_.reset();
crc_generator_.add(Storage::Encodings::MFM::DataAddressByte);
crc_generator_.add(latest_token_.byte_value = Storage::Encodings::MFM::DataAddressByte);
break;
case Storage::Encodings::MFM::FMDeletedDataAddressMark:
token_type = Token::DeletedData;
crc_generator_.reset();
crc_generator_.add(Storage::Encodings::MFM::DeletedDataAddressByte);
crc_generator_.add(latest_token_.byte_value = Storage::Encodings::MFM::DeletedDataAddressByte);
break;
default:
break;
@ -203,12 +203,18 @@ void WD1770::process_input_bit(int value, unsigned int cycles_since_index_hole)
case Storage::Encodings::MFM::MFMIndexSync:
bits_since_token_ = 0;
is_awaiting_marker_value_ = true;
return;
token_type = Token::Sync;
latest_token_.byte_value = Storage::Encodings::MFM::MFMIndexSyncByteValue;
break;
case Storage::Encodings::MFM::MFMSync:
bits_since_token_ = 0;
is_awaiting_marker_value_ = true;
crc_generator_.set_value(Storage::Encodings::MFM::MFMPostSyncCRCValue);
return;
token_type = Token::Sync;
latest_token_.byte_value = Storage::Encodings::MFM::MFMSyncByteValue;
break;
default:
break;
}
@ -763,6 +769,26 @@ void WD1770::posit_event(Event new_event_type)
update_status([] (Status &status) {
status.type = Status::Three;
});
if(!has_motor_on_line() && !has_head_load_line()) goto type3_test_delay;
if(has_motor_on_line()) goto begin_type3_spin_up;
goto begin_type3_load_head;
begin_type3_load_head:
set_head_load_request(true);
if(head_is_loaded_) goto type3_test_delay;
WAIT_FOR_EVENT(Event::HeadLoad);
goto type3_test_delay;
begin_type3_spin_up:
if((command_&0x08) || get_motor_on()) goto type3_test_delay;
SPIN_UP();
type3_test_delay:
if(!(command_&0x04)) goto test_type3_type;
WAIT_FOR_TIME(30);
test_type3_type:
switch(command_ >> 4)
{
case 0xa: goto begin_read_address;
@ -774,24 +800,33 @@ void WD1770::posit_event(Event new_event_type)
printf("!!!TODO: read address!!!\n");
begin_read_track:
printf("!!!TODO: read track!!!\n");
WAIT_FOR_EVENT(Event::IndexHole);
index_hole_count_ = 0;
read_track_read_byte:
WAIT_FOR_EVENT(Event::Token | Event::IndexHole);
if(index_hole_count_)
{
goto wait_for_command;
}
if(status_.data_request)
{
update_status([] (Status &status) {
status.lost_data = true;
});
goto wait_for_command;
}
data_ = latest_token_.byte_value;
update_status([] (Status &status) {
status.data_request = true;
});
goto read_track_read_byte;
begin_write_track:
update_status([] (Status &status) {
status.data_request = false;
status.lost_data = false;
});
set_motor_on(true);
if(!(command_ & 0x08) || !has_motor_on_line()) goto write_track_test_delay;
index_hole_count_ = 0;
write_track_test_index_hole_count:
WAIT_FOR_EVENT(Event::IndexHoleTarget);
if(index_hole_count_target_ < 6) goto write_track_test_index_hole_count;
write_track_test_delay:
if(!(command_&0x04)) goto write_track_test_write_protect;
WAIT_FOR_TIME(30);
write_track_test_write_protect:
if(get_drive_is_read_only())

2
Components/1770/1770.hpp
View File

@ -104,7 +104,7 @@ class WD1770: public Storage::Disk::Controller {
int shift_register_;
struct Token {
enum Type {
Index, ID, Data, DeletedData, Byte
Index, ID, Data, DeletedData, Sync, Byte
} type;
uint8_t byte_value;
} latest_token_;

3
Storage/Disk/Encodings/MFM.hpp
View File

@ -33,6 +33,9 @@ const uint16_t MFMIndexSync = 0x5224; // data 0xc2, with a missing clock at 0
const uint16_t MFMSync = 0x4489; // data 0xa1, with a missing clock at 0x0020 => 0100 0100 1010 1001 without 0010 0000
const uint16_t MFMPostSyncCRCValue = 0xcdb4; // the value the CRC generator should have after encountering three 0xa1s
const uint8_t MFMIndexSyncByteValue = 0xc2;
const uint8_t MFMSyncByteValue = 0xa1;
struct Sector {
uint8_t track, side, sector;
std::vector<uint8_t> data;