mirror of
https://github.com/davidgiven/fluxengine.git
synced 2025-10-31 11:17:01 -07:00
d303067deb
mapping is now done at the last stage and should, ideally, be automatic. I'm sure there are bugs everywhere.
87 lines
2.5 KiB
C++
87 lines
2.5 KiB
C++
#include "globals.h"
|
|
#include "fluxmap.h"
|
|
#include "decoders/fluxmapreader.h"
|
|
#include "protocol.h"
|
|
#include "decoders/decoders.h"
|
|
#include "sector.h"
|
|
#include "amiga.h"
|
|
#include "bytes.h"
|
|
#include "fmt/format.h"
|
|
#include "lib/decoders/decoders.pb.h"
|
|
#include <string.h>
|
|
#include <algorithm>
|
|
|
|
/*
|
|
* Amiga disks use MFM but it's not quite the same as IBM MFM. They only use
|
|
* a single type of record with a different marker byte.
|
|
*
|
|
* See the big comment in the IBM MFM decoder for the gruesome details of how
|
|
* MFM works.
|
|
*/
|
|
|
|
static const FluxPattern SECTOR_PATTERN(48, AMIGA_SECTOR_RECORD);
|
|
|
|
class AmigaDecoder : public AbstractDecoder
|
|
{
|
|
public:
|
|
AmigaDecoder(const DecoderProto& config):
|
|
AbstractDecoder(config),
|
|
_config(config.amiga())
|
|
{}
|
|
|
|
nanoseconds_t advanceToNextRecord() override
|
|
{
|
|
return seekToPattern(SECTOR_PATTERN);
|
|
}
|
|
|
|
void decodeSectorRecord() override
|
|
{
|
|
if (readRaw48() != AMIGA_SECTOR_RECORD)
|
|
return;
|
|
|
|
const auto& rawbits = readRawBits(AMIGA_RECORD_SIZE*16);
|
|
if (rawbits.size() < (AMIGA_RECORD_SIZE*16))
|
|
return;
|
|
const auto& rawbytes = toBytes(rawbits).slice(0, AMIGA_RECORD_SIZE*2);
|
|
const auto& bytes = decodeFmMfm(rawbits).slice(0, AMIGA_RECORD_SIZE);
|
|
|
|
const uint8_t* ptr = bytes.begin();
|
|
|
|
Bytes header = amigaDeinterleave(ptr, 4);
|
|
Bytes recoveryinfo = amigaDeinterleave(ptr, 16);
|
|
|
|
_sector->logicalTrack = header[1] >> 1;
|
|
_sector->logicalSide = header[1] & 1;
|
|
_sector->logicalSector = header[2];
|
|
|
|
uint32_t wantedheaderchecksum = amigaDeinterleave(ptr, 4).reader().read_be32();
|
|
uint32_t gotheaderchecksum = amigaChecksum(rawbytes.slice(0, 40));
|
|
if (gotheaderchecksum != wantedheaderchecksum)
|
|
return;
|
|
|
|
uint32_t wanteddatachecksum = amigaDeinterleave(ptr, 4).reader().read_be32();
|
|
uint32_t gotdatachecksum = amigaChecksum(rawbytes.slice(56, 1024));
|
|
|
|
Bytes data;
|
|
data.writer().append(amigaDeinterleave(ptr, 512)).append(recoveryinfo);
|
|
_sector->data = data;
|
|
_sector->status = (gotdatachecksum == wanteddatachecksum) ? Sector::OK : Sector::BAD_CHECKSUM;
|
|
}
|
|
|
|
std::set<unsigned> requiredSectors(const Location&) const override
|
|
{
|
|
static std::set<unsigned> sectors = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
|
|
return sectors;
|
|
}
|
|
|
|
private:
|
|
const AmigaDecoderProto& _config;
|
|
nanoseconds_t _clock;
|
|
};
|
|
|
|
std::unique_ptr<AbstractDecoder> createAmigaDecoder(const DecoderProto& config)
|
|
{
|
|
return std::unique_ptr<AbstractDecoder>(new AmigaDecoder(config));
|
|
}
|
|
|