static BYTE __stdcall DiskControlStepper(WORD, WORD address, BYTE, BYTE, ULONG)
{
Disk_t * fptr = &g_aFloppyDisk[currdrive];
#if 1
int phase = (address >> 1) & 3;
int phase_bit = (1 << phase);
// update the magnet states
if (address & 1)
{
// phase on
phases |= phase_bit;
LOG_DISK("track %02X phases %X phase %d on address $C0E%X\r", fptr->phase, phases, phase, address & 0xF);
}
else
{
// phase off
phases &= ~phase_bit;
LOG_DISK("track %02X phases %X phase %d off address $C0E%X\r", fptr->phase, phases, phase, address & 0xF);
}
// check for any stepping effect from a magnet
// - move only when the magnet opposite the cog is off
// - move in the direction of an adjacent magnet if one is on
// - do not move if both adjacent magnets are on
// momentum and timing are not accounted for ... maybe one day!
int direction = 0;
if (phases & (1 << ((fptr->phase + 1) & 3)))
direction += 1;
if (phases & (1 << ((fptr->phase + 3) & 3)))
direction -= 1;
// apply magnet step, if any
if (direction)
{
fptr->phase = MAX(0, MIN(79, fptr->phase + direction));
const int nNumTracksInImage = ImageGetNumTracks(fptr->imagehandle);
const int newtrack = (nNumTracksInImage == 0) ? 0
: MIN(nNumTracksInImage-1, fptr->phase >> 1); // (round half tracks down)
LOG_DISK("newtrack %2X%s\r", newtrack, (fptr->phase & 1) ? ".5" : "");
if (newtrack != fptr->track)
{
if (fptr->trackimage && fptr->trackimagedirty)
{
WriteTrack(currdrive);
}
fptr->track = newtrack;
fptr->trackimagedata = 0;
}
// Feature Request #201 Show track status
// https://github.com/AppleWin/AppleWin/issues/201
FrameDrawDiskStatus( (HDC)0 );
}
#else // Old 1.13.1 code for Chessmaster 2000 to work! (see bug#18109)
const int nNumTracksInImage = ImageGetNumTracks(fptr->imagehandle);
if (address & 1) {
int phase = (address >> 1) & 3;
int direction = 0;
if (phase == ((fptr->phase+1) & 3))
direction = 1;
if (phase == ((fptr->phase+3) & 3))
direction = -1;
if (direction) {
fptr->phase = MAX(0,MIN(79,fptr->phase+direction));
if (!(fptr->phase & 1)) {
int newtrack = MIN(nNumTracksInImage-1,fptr->phase >> 1);
if (newtrack != fptr->track) {
if (fptr->trackimage && fptr->trackimagedirty)
WriteTrack(currdrive);
fptr->track = newtrack;
fptr->trackimagedata = 0;
}
}
}
void __stdcall Disk2InterfaceCard::ControlStepper(WORD, WORD address, BYTE, BYTE, ULONG uExecutedCycles)
{
FloppyDrive* pDrive = &m_floppyDrive[m_currDrive];
FloppyDisk* pFloppy = &pDrive->m_disk;
if (!m_floppyMotorOn) // GH#525
{
if (!pDrive->m_spinning)
{
#if LOG_DISK_PHASES
LOG_DISK("stepper accessed whilst motor is off and not spinning\r\n");
#endif
return;
}
#if LOG_DISK_PHASES
LOG_DISK("stepper accessed whilst motor is off, but still spinning\r\n");
#endif
}
int phase = (address >> 1) & 3;
int phase_bit = (1 << phase);
#if 1
// update the magnet states
if (address & 1)
{
// phase on
m_phases |= phase_bit;
}
else
{
// phase off
m_phases &= ~phase_bit;
}
// check for any stepping effect from a magnet
// - move only when the magnet opposite the cog is off
// - move in the direction of an adjacent magnet if one is on
// - do not move if both adjacent magnets are on
// momentum and timing are not accounted for ... maybe one day!
int direction = 0;
if (m_phases & (1 << ((pDrive->m_phase + 1) & 3)))
direction += 1;
if (m_phases & (1 << ((pDrive->m_phase + 3) & 3)))
direction -= 1;
// apply magnet step, if any
if (direction)
{
pDrive->m_phase = MAX(0, MIN(79, pDrive->m_phase + direction));
const int nNumTracksInImage = ImageGetNumTracks(pFloppy->m_imagehandle);
const int newtrack = (nNumTracksInImage == 0) ? 0
: MIN(nNumTracksInImage-1, pDrive->m_phase >> 1); // (round half tracks down)
if (newtrack != pDrive->m_track)
{
FlushCurrentTrack(m_currDrive);
pDrive->m_track = newtrack;
pFloppy->m_trackimagedata = false;
m_formatTrack.DriveNotWritingTrack();
}
// Feature Request #201 Show track status
// https://github.com/AppleWin/AppleWin/issues/201
FrameDrawDiskStatus( (HDC)0 );
}
#else
// substitute alternate stepping code here to test
#endif
#if LOG_DISK_PHASES
LOG_DISK("track $%02X%s phases %d%d%d%d phase %d %s address $%4X\r\n",
pDrive->m_phase >> 1,
(pDrive->m_phase & 1) ? ".5" : " ",
(m_phases >> 3) & 1,
(m_phases >> 2) & 1,
(m_phases >> 1) & 1,
(m_phases >> 0) & 1,
phase,
(address & 1) ? "on " : "off",
address);
#endif
}
