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mirror of https://github.com/TomHarte/CLK.git synced 2024-06-29 00:29:34 +00:00

Breaks video output while attempting to pull it into the main loop.

This commit is contained in:
Thomas Harte 2021-07-27 21:33:07 -04:00
parent b6bf4d73ad
commit 402eab10f8
2 changed files with 92 additions and 92 deletions

View File

@ -126,6 +126,89 @@ bool Chipset::Copper::advance(uint16_t position) {
return true;
}
template <int cycle> void Chipset::output() {
// Hardware stop is at 0x18;
// 12/64 * 227 = 42.5625
//
// "However, horizontal blanking actually limits the displayable
// video to 368 low resolution pixel"
//
// => 184 windows out of 227 are visible, which concurs.
//
// A complete from-thin-air guess:
//
// 7 cycles blank;
// 17 cycles sync;
// 3 cycles blank;
// 9 cycles colour burst;
// 7 cycles blank.
constexpr int blank1 = 7;
constexpr int sync = 17 + blank1;
constexpr int blank2 = 3 + sync;
constexpr int burst = 9 + blank2;
constexpr int blank3 = 7 + burst;
static_assert(blank3 == 43);
#define LINK(location, action, length) \
if(cycle == (location)) { \
crt_.action((length) * 4); \
}
if(y_ < vertical_blank_height_) {
// Put three lines of sync at the centre of the vertical blank period.
// Offset by half a line if interlaced and on an odd frame.
const int midline = vertical_blank_height_ >> 1;
if(frame_height_ & 1) {
if(y_ < midline - 1 || y_ > midline + 2) {
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(line_length_ - 1, output_blank, line_length_ - 1 - sync);
} else if(y_ == midline - 1) {
LINK(113, output_blank, 113);
LINK(line_length_ - 1, output_sync, line_length_ - 1 - 113);
} else if(y_ == midline + 2) {
LINK(113, output_sync, 113);
LINK(line_length_ - 1, output_blank, line_length_ - 1 - 113);
} else {
LINK(blank1, output_sync, blank1);
LINK(sync, output_blank, sync - blank1);
LINK(line_length_ - 1, output_sync, line_length_ - 1 - sync);
}
} else {
if(y_ < midline - 1 || y_ > midline + 1) {
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(line_length_ - 1, output_blank, line_length_ - 1 - sync);
} else {
LINK(blank1, output_sync, blank1);
LINK(sync, output_blank, sync - blank1);
LINK(line_length_ - 1, output_sync, line_length_ - 1 - sync);
}
}
} else {
// Output the correct sequence of blanks, syncs and burst atomically.
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(blank2, output_blank, blank2 - sync);
LINK(burst, output_default_colour_burst, burst - blank2); // TODO: only if colour enabled.
LINK(blank3, output_blank, blank3 - burst);
// Output colour 0 to fill the rest of the line; Kickstart uses this
// colour to post the error code. TODO: actual pixels, etc.
if(cycle == line_length_ - 1) {
uint16_t *const pixels = reinterpret_cast<uint16_t *>(crt_.begin_data(1));
if(pixels) {
*pixels = palette_[0];
}
crt_.output_data((cycle - blank3) * 4, 1);
}
}
#undef LINK
}
template <int cycle, bool stop_if_cpu> bool Chipset::perform_cycle() {
// TODO: actual CPU scheduling.
if constexpr (stop_if_cpu) {
@ -169,8 +252,7 @@ template <bool stop_on_cpu> Chipset::Changes Chipset::run(HalfCycles length) {
// Update raster position, spooling out graphics.
while(pixels_remaining) {
// Determine number of pixels left on this line.
int line_pixels = std::min(pixels_remaining, line_length_ - line_cycle_);
pixels_remaining -= line_pixels;
int line_pixels = std::min(pixels_remaining, (line_length_ * 4) - line_cycle_);
//
// Run DMA scheduler.
@ -187,10 +269,12 @@ template <bool stop_on_cpu> Chipset::Changes Chipset::run(HalfCycles length) {
// Advance to window boundary.
const int distance_to_boundary = ((line_cycle_ - 1) & 3) ^ 3;
line_pixels -= distance_to_boundary;
pixels_remaining -= distance_to_boundary;
line_cycle_ += distance_to_boundary;
#define C(x) \
case x: \
assert(!(line_cycle_&3)); \
if constexpr(stop_on_cpu) {\
if(perform_cycle<x, stop_on_cpu>()) {\
break;\
@ -198,8 +282,10 @@ template <bool stop_on_cpu> Chipset::Changes Chipset::run(HalfCycles length) {
} else {\
perform_cycle<x, stop_on_cpu>(); \
} \
output<x>(); \
if((line_cycle_ >> 2) == final_slot) break; \
line_cycle_ += 4;
line_cycle_ += 4; \
pixels_remaining -= 4;
#define C10(x) C(x); C(x+1); C(x+2); C(x+3); C(x+4); C(x+5); C(x+6); C(x+7); C(x+8); C(x+9);
switch(line_cycle_ >> 2) {
@ -215,95 +301,9 @@ template <bool stop_on_cpu> Chipset::Changes Chipset::run(HalfCycles length) {
}
#undef C
// Update per the possibility that the above ended early.
final_slot = line_cycle_ >> 2;
int slot = line_cycle_ >> 2;
//
// Output video signal as implied by whatever happened above.
//
// Hardware stop is at 0x18;
// 12/64 * 227 = 42.5625
//
// "However, horizontal blanking actually limits the displayable
// video to 368 low resolution pixel"
//
// => 184 windows out of 227 are visible, which concurs.
//
// A complete from-thin-air guess:
//
// 7 cycles blank;
// 17 cycles sync;
// 3 cycles blank;
// 9 cycles colour burst;
// 7 cycles blank.
constexpr int blank1 = 7;
constexpr int sync = 17 + blank1;
constexpr int blank2 = 3 + sync;
constexpr int burst = 9 + blank2;
constexpr int blank3 = 7 + burst;
static_assert(blank3 == 43);
#define LINK(location, action, length) \
if(slot < (location) && final_slot >= (location)) { \
crt_.action((length) * 4); \
}
if(y_ < vertical_blank_height_) {
// Put three lines of sync at the centre of the vertical blank period.
// TODO: offset by half a line if interlaced and on an odd frame.
const int midline = vertical_blank_height_ >> 1;
if(frame_height_ & 1) {
if(y_ < midline - 1 || y_ > midline + 2) {
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(line_length_, output_blank, line_length_ - sync);
} else if(y_ == midline - 1) {
LINK(113, output_blank, 113);
LINK(line_length_, output_sync, line_length_ - 113);
} else if(y_ == midline + 2) {
LINK(113, output_sync, 113);
LINK(line_length_, output_blank, line_length_ - 113);
} else {
LINK(blank1, output_sync, blank1);
LINK(sync, output_blank, sync - blank1);
LINK(line_length_, output_sync, line_length_ - sync);
}
} else {
if(y_ < midline - 1 || y_ > midline + 1) {
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(line_length_, output_blank, line_length_ - sync);
} else {
LINK(blank1, output_sync, blank1);
LINK(sync, output_blank, sync - blank1);
LINK(line_length_, output_sync, line_length_ - sync);
}
}
} else {
// Output the correct sequence of blanks, syncs and burst atomically.
LINK(blank1, output_blank, blank1);
LINK(sync, output_sync, sync - blank1);
LINK(blank2, output_blank, blank2 - sync);
LINK(burst, output_default_colour_burst, burst - blank2); // TODO: only if colour enabled.
LINK(blank3, output_blank, blank3 - burst);
// Output colour 0 to fill the rest of the line; Kickstart uses this
// colour to post the error code. TODO: actual pixels, etc.
if(line_cycle_ == line_length_) {
uint16_t *const pixels = reinterpret_cast<uint16_t *>(crt_.begin_data(1));
if(pixels) {
*pixels = palette_[0];
}
crt_.output_data(line_length_ - blank3 * 4, 1);
}
}
// Advance intraline counter and possibly ripple upwards into
// lines and fields.
if(line_cycle_ == line_length_) {
if(line_cycle_ == (line_length_ * 4)) {
++changes.hsyncs;
line_cycle_ = 0;
@ -321,7 +321,6 @@ template <bool stop_on_cpu> Chipset::Changes Chipset::run(HalfCycles length) {
}
}
}
#undef LINK
changes.interrupt_level = interrupt_level_;
changes.duration = length;

View File

@ -67,6 +67,7 @@ class Chipset {
template <bool stop_on_cpu> Changes run(HalfCycles duration = HalfCycles());
template <int cycle, bool stop_if_cpu> bool perform_cycle();
template <int cycle> void output();
// MARK: - DMA Control, Scheduler and Blitter.
@ -85,7 +86,7 @@ class Chipset {
// MARK: - Raster.
int line_cycle_ = 0, y_ = 0;
int line_length_ = 227 * 4;
int line_length_ = 227;
int frame_height_ = 312;
int vertical_blank_height_ = 29;