Files
fluxengine/arch/zilogmcz/decoder.cc
2024-10-15 00:00:27 +02:00

57 lines
1.5 KiB
C++

#include "lib/core/globals.h"
#include "lib/data/fluxmap.h"
#include "lib/data/fluxmapreader.h"
#include "lib/data/fluxpattern.h"
#include "protocol.h"
#include "lib/decoders/decoders.h"
#include "lib/data/sector.h"
#include "zilogmcz.h"
#include "lib/core/bytes.h"
#include "lib/core/crc.h"
#include "fmt/format.h"
#include <string.h>
#include <algorithm>
static const FluxPattern SECTOR_START_PATTERN(16, 0xaaab);
class ZilogMczDecoder : public Decoder
{
public:
ZilogMczDecoder(const DecoderProto& config): Decoder(config) {}
nanoseconds_t advanceToNextRecord() override
{
seekToIndexMark();
return seekToPattern(SECTOR_START_PATTERN);
}
void decodeSectorRecord() override
{
readRawBits(14);
auto rawbits = readRawBits(140 * 16);
auto bytes = decodeFmMfm(rawbits).slice(0, 140);
ByteReader br(bytes);
_sector->logicalSector = br.read_8() & 0x1f;
_sector->logicalSide = 0;
_sector->logicalTrack = br.read_8() & 0x7f;
if (_sector->logicalSector > 31)
return;
if (_sector->logicalTrack > 80)
return;
_sector->data = br.read(132);
uint16_t wantChecksum = br.read_be16();
uint16_t gotChecksum = crc16(MODBUS_POLY, 0x0000, bytes.slice(0, 134));
_sector->status =
(wantChecksum == gotChecksum) ? Sector::OK : Sector::BAD_CHECKSUM;
}
};
std::unique_ptr<Decoder> createZilogMczDecoder(const DecoderProto& config)
{
return std::unique_ptr<Decoder>(new ZilogMczDecoder(config));
}