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MemoryCard: Formatting

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This commit is contained in:
Connor McLaughlin 2019-09-30 01:53:47 +10:00
parent f3663fa018
commit 623b9996c7
2 changed files with 77 additions and 2 deletions
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73
src/pse/memory_card.cpp
View file

@ -5,6 +5,7 @@ Log_SetChannel(MemoryCard);
MemoryCard::MemoryCard()
{
m_FLAG.no_write_yet = true;
Format();
}
MemoryCard::~MemoryCard() = default;
@ -72,7 +73,7 @@ bool MemoryCard::Transfer(const u8 data_in, u8* data_out)
const u8 bits = m_data[ZeroExtend32(m_address) * SECTOR_SIZE + m_sector_offset];
if (m_sector_offset == 0)
{
Log_DebugPrintf("Reading memory card sector %u", ZeroExtend32(m_address));
Log_DevPrintf("Reading memory card sector %u", ZeroExtend32(m_address));
m_checksum = Truncate8(m_address >> 8) ^ Truncate8(m_address) ^ bits;
}
else
@ -106,7 +107,7 @@ bool MemoryCard::Transfer(const u8 data_in, u8* data_out)
{
if (m_sector_offset == 0)
{
Log_DebugPrintf("Writing memory card sector %u", ZeroExtend32(m_address));
Log_DevPrintf("Writing memory card sector %u", ZeroExtend32(m_address));
m_checksum = Truncate8(m_address >> 8) ^ Truncate8(m_address) ^ data_in;
}
else
@ -191,3 +192,71 @@ std::shared_ptr<MemoryCard> MemoryCard::Create()
{
return std::make_shared<MemoryCard>();
}
u8 MemoryCard::ChecksumFrame(const u8* fptr)
{
u8 value = fptr[0];
for (u32 i = 0; i < SECTOR_SIZE; i++)
value ^= fptr[i];
return value;
}
void MemoryCard::Format()
{
// fill everything with FF
m_data.fill(u8(0xFF));
// header
{
u8* fptr = GetSectorPtr(0);
std::fill_n(fptr, SECTOR_SIZE, u8(0));
fptr[0] = 'M';
fptr[1] = 'C';
fptr[0x7F] = ChecksumFrame(&m_data[0]);
}
// directory
for (u32 frame = 1; frame < 16; frame++)
{
u8* fptr = GetSectorPtr(frame);
std::fill_n(fptr, SECTOR_SIZE, u8(0));
fptr[0] = 0xA0; // free
fptr[0x7F] = ChecksumFrame(fptr); // checksum
}
// broken sector list
for (u32 frame = 16; frame < 36; frame++)
{
u8* fptr = GetSectorPtr(frame);
std::fill_n(fptr, SECTOR_SIZE, u8(0));
fptr[0] = 0xFF;
fptr[1] = 0xFF;
fptr[2] = 0xFF;
fptr[3] = 0xFF;
fptr[0x7F] = ChecksumFrame(fptr); // checksum
}
// broken sector replacement data
for (u32 frame = 36; frame < 56; frame++)
{
u8* fptr = GetSectorPtr(frame);
std::fill_n(fptr, SECTOR_SIZE, u8(0xFF));
}
// unused frames
for (u32 frame = 56; frame < 63; frame++)
{
u8* fptr = GetSectorPtr(frame);
std::fill_n(fptr, SECTOR_SIZE, u8(0xFF));
}
// write test frame
std::memcpy(GetSectorPtr(63), GetSectorPtr(0), SECTOR_SIZE);
}
u8* MemoryCard::GetSectorPtr(u32 sector)
{
Assert(sector < NUM_SECTORS);
return &m_data[sector * SECTOR_SIZE];
}

6
src/pse/memory_card.h
View file

@ -22,6 +22,8 @@ public:
void ResetTransferState() override;
bool Transfer(const u8 data_in, u8* data_out) override;
void Format();
private:
union FLAG
{
@ -60,6 +62,10 @@ private:
WriteEnd,
};
static u8 ChecksumFrame(const u8* fptr);
u8* GetSectorPtr(u32 sector);
State m_state = State::Idle;
u16 m_address = 0;
u8 m_sector_offset = 0;