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flopimg: Fix issues when wrapping in generate_bitstream_from_track which were especially damaging for apple drivers

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Olivier Galibert 2022-04-19 17:53:17 +02:00
parent 6d3c4ff49a
commit 5b17570612
1 changed files with 119 additions and 69 deletions
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188
src/lib/formats/flopimg.cpp
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@ -1316,92 +1316,142 @@ std::vector<bool> floppy_image_format_t::generate_bitstream_from_track(int track
return trackbuf; return trackbuf;
} }
// Start at the write splice class pll {
uint32_t splice = image->get_write_splice_position(track, head, subtrack); private:
int cur_pos = splice; const std::vector<uint32_t> &tbuf;
int cur_entry = 0; int cur_pos;
while(cur_entry < int(tbuf.size())-1 && (tbuf[cur_entry+1] & floppy_image::TIME_MASK) < cur_pos) int cur_entry;
cur_entry++; int period;
int period_adjust_base;
int min_period;
int max_period;
int phase_adjust;
int freq_hist;
bool next_is_first;
int period = cell_size; public:
int period_adjust_base = period * 0.05; pll(const std::vector<uint32_t> &_tbuf, int cell_size) : tbuf(_tbuf) {
period = cell_size;
period_adjust_base = period * 0.05;
int min_period = int(cell_size*0.75); min_period = int(cell_size*0.75);
int max_period = int(cell_size*1.25); max_period = int(cell_size*1.25);
int phase_adjust = 0; phase_adjust = 0;
int freq_hist = 0; freq_hist = 0;
uint32_t scanned = 0; // Try to go back 16 flux changes from the end of the track, or at most at the start
while(scanned < 200000000) { int flux_to_step = 16;
// Note that only MG_F edges are taken into account, the rest is ignored. cur_entry = tbuf.size()-1;
// The lack of MG_F has been tested for previously. while(cur_entry > 0 && flux_to_step) {
while((tbuf[cur_entry] & floppy_image::MG_MASK) != floppy_image::MG_F) { if((tbuf[cur_entry] & floppy_image::MG_MASK) == floppy_image::MG_F)
cur_entry ++; flux_to_step --;
if(cur_entry == tbuf.size()) cur_entry--;
cur_entry = 0; }
// Go back by half-a-period
cur_pos = (tbuf[cur_entry] & floppy_image::TIME_MASK) - period/2;
// Adjust the entry accordingly
while(cur_entry > 0 && (cur_pos > (tbuf[cur_entry] & floppy_image::TIME_MASK)))
cur_entry --;
// Now go to the next flux change from there (the no-MG_F case has been handled earlier)
while((tbuf[cur_entry] & floppy_image::MG_MASK) != floppy_image::MG_F)
cur_entry ++;
next_is_first = false;
} }
int edge = tbuf[cur_entry] & floppy_image::TIME_MASK; std::pair<bool, bool> get() {
if(edge < cur_pos) bool bit, first;
edge += 200000000; int edge = tbuf[cur_entry] & floppy_image::TIME_MASK;
int next = cur_pos + period + phase_adjust; if(edge < cur_pos)
scanned += period + phase_adjust; edge += 200000000;
int next = cur_pos + period + phase_adjust;
if(edge >= next) { if(edge >= next) {
// No transition in the window means 0 and pll in free run mode // No transition in the window means 0 and pll in free run mode
trackbuf.push_back(false); bit = false;
phase_adjust = 0; phase_adjust = 0;
} else { } else {
// Transition in the window means 1, and the pll is adjusted // Transition in the window means 1, and the pll is adjusted
trackbuf.push_back(true); bit = true;
int delta = edge - (next - period/2); int delta = edge - (next - period/2);
phase_adjust = 0.65*delta; phase_adjust = 0.65*delta;
if(delta < 0) { if(delta < 0) {
if(freq_hist < 0) if(freq_hist < 0)
freq_hist--; freq_hist--;
else else
freq_hist = -1; freq_hist = -1;
} else if(delta > 0) { } else if(delta > 0) {
if(freq_hist > 0) if(freq_hist > 0)
freq_hist++; freq_hist++;
else else
freq_hist = 1; freq_hist = 1;
} else } else
freq_hist = 0; freq_hist = 0;
if(freq_hist) { if(freq_hist) {
int afh = freq_hist < 0 ? -freq_hist : freq_hist; int afh = freq_hist < 0 ? -freq_hist : freq_hist;
if(afh > 1) { if(afh > 1) {
int aper = period_adjust_base*delta/period; int aper = period_adjust_base*delta/period;
if(!aper) if(!aper)
aper = freq_hist < 0 ? -1 : 1; aper = freq_hist < 0 ? -1 : 1;
period += aper; period += aper;
if(period < min_period) if(period < min_period)
period = min_period; period = min_period;
else if(period > max_period) else if(period > max_period)
period = max_period; period = max_period;
}
} }
} }
}
cur_pos = next; first = next_is_first;
if(cur_pos >= 200000000) { next_is_first = false;
cur_pos -= 200000000;
cur_entry = 0;
}
while(cur_entry < int(tbuf.size())-1 && (tbuf[cur_entry] & floppy_image::TIME_MASK) < cur_pos)
cur_entry++;
// Wrap around cur_pos = next;
if(cur_entry == int(tbuf.size())-1 && if(cur_pos >= 200000000) {
(tbuf[cur_entry] & floppy_image::TIME_MASK) < cur_pos) cur_pos -= 200000000;
cur_entry = 0; cur_entry = 0;
if(cur_pos >= period/2)
first = true;
else
next_is_first = true;
}
while(cur_entry < int(tbuf.size())-1 && (tbuf[cur_entry] & floppy_image::TIME_MASK) < cur_pos)
cur_entry++;
// Wrap around
if(cur_entry == int(tbuf.size())-1 &&
(tbuf[cur_entry] & floppy_image::TIME_MASK) < cur_pos)
cur_entry = 0;
return std::make_pair(bit, first);
}
};
pll cpll(tbuf, cell_size);
for(;;) {
auto r = cpll.get();
if(r.second) {
trackbuf.push_back(r.first);
break;
}
} }
for(;;) {
auto r = cpll.get();
if(r.second)
break;
trackbuf.push_back(r.first);
}
return trackbuf; return trackbuf;
} }