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Convert the Durango F85 decoder.

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This commit is contained in:
David Given
2021-07-11 15:50:35 +02:00
parent 1fa2547aff
commit aed9e44b6b
3 changed files with 58 additions and 61 deletions
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100
arch/f85/decoder.cc
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@@ -52,49 +52,63 @@ static Bytes decode(const std::vector<bool>& bits)
return output;
}
AbstractDecoder::RecordType DurangoF85Decoder::advanceToNextRecord()
class DurangoF85Decoder : public AbstractDecoder
{
const FluxMatcher* matcher = nullptr;
_sector->clock = _fmr->seekToPattern(ANY_RECORD_PATTERN, matcher);
if (matcher == &SECTOR_RECORD_PATTERN)
return RecordType::SECTOR_RECORD;
if (matcher == &DATA_RECORD_PATTERN)
return RecordType::DATA_RECORD;
return RecordType::UNKNOWN_RECORD;
public:
DurangoF85Decoder(const DecoderProto& config):
AbstractDecoder(config)
{}
RecordType advanceToNextRecord()
{
const FluxMatcher* matcher = nullptr;
_sector->clock = _fmr->seekToPattern(ANY_RECORD_PATTERN, matcher);
if (matcher == &SECTOR_RECORD_PATTERN)
return RecordType::SECTOR_RECORD;
if (matcher == &DATA_RECORD_PATTERN)
return RecordType::DATA_RECORD;
return RecordType::UNKNOWN_RECORD;
}
void decodeSectorRecord()
{
/* Skip sync bits and ID byte. */
readRawBits(24);
/* Read header. */
const auto& bytes = decode(readRawBits(6*10));
_sector->logicalSector = bytes[2];
_sector->logicalSide = 0;
_sector->logicalTrack = bytes[0];
uint16_t wantChecksum = bytes.reader().seek(4).read_be16();
uint16_t gotChecksum = crc16(CCITT_POLY, 0xef21, bytes.slice(0, 4));
if (wantChecksum == gotChecksum)
_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
}
void decodeDataRecord()
{
/* Skip sync bits ID byte. */
readRawBits(24);
const auto& bytes = decode(readRawBits((F85_SECTOR_LENGTH+3)*10))
.slice(0, F85_SECTOR_LENGTH+3);
ByteReader br(bytes);
_sector->data = br.read(F85_SECTOR_LENGTH);
uint16_t wantChecksum = br.read_be16();
uint16_t gotChecksum = crc16(CCITT_POLY, 0xbf84, _sector->data);
_sector->status = (wantChecksum == gotChecksum) ? Sector::OK : Sector::BAD_CHECKSUM;
}
};
std::unique_ptr<AbstractDecoder> createDurangoF85Decoder(const DecoderProto& config)
{
return std::unique_ptr<AbstractDecoder>(new DurangoF85Decoder(config));
}
void DurangoF85Decoder::decodeSectorRecord()
{
/* Skip sync bits and ID byte. */
readRawBits(24);
/* Read header. */
const auto& bytes = decode(readRawBits(6*10));
_sector->logicalSector = bytes[2];
_sector->logicalSide = 0;
_sector->logicalTrack = bytes[0];
uint16_t wantChecksum = bytes.reader().seek(4).read_be16();
uint16_t gotChecksum = crc16(CCITT_POLY, 0xef21, bytes.slice(0, 4));
if (wantChecksum == gotChecksum)
_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
}
void DurangoF85Decoder::decodeDataRecord()
{
/* Skip sync bits ID byte. */
readRawBits(24);
const auto& bytes = decode(readRawBits((F85_SECTOR_LENGTH+3)*10))
.slice(0, F85_SECTOR_LENGTH+3);
ByteReader br(bytes);
_sector->data = br.read(F85_SECTOR_LENGTH);
uint16_t wantChecksum = br.read_be16();
uint16_t gotChecksum = crc16(CCITT_POLY, 0xbf84, _sector->data);
_sector->status = (wantChecksum == gotChecksum) ? Sector::OK : Sector::BAD_CHECKSUM;
}