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Eliminates the full_frame_counter_ and slightly tweaks NTSC raster timing.

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Thomas Harte 2018-04-08 18:51:20 -04:00
parent f541986333
commit cf6f6c5c15
1 changed files with 4 additions and 5 deletions
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9
Components/6560/6560.hpp
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@ -138,7 +138,7 @@ template <class T> class MOS6560 {
chrominances = ntsc_chrominances;
display_type = Outputs::CRT::DisplayType::NTSC60;
timing_.cycles_per_line = 65;
timing_.line_counter_increment_offset = 65 - 33; // TODO: this is a bit of a hack; separate vertical and horizontal counting
timing_.line_counter_increment_offset = 34; // Indicates that the raster count increments 34 cycles ahead of the vertical counter overflowing.
timing_.lines_per_progressive_field = 261;
timing_.supports_interlacing = true;
break;
@ -176,7 +176,6 @@ template <class T> class MOS6560 {
// keep track of internal time relative to this scanline
horizontal_counter_++;
full_frame_counter_++;
if(horizontal_counter_ == timing_.cycles_per_line) {
if(horizontal_drawing_latch_) {
current_character_row_++;
@ -200,7 +199,6 @@ template <class T> class MOS6560 {
vertical_counter_ ++;
if(vertical_counter_ == lines_this_field()) {
vertical_counter_ = 0;
full_frame_counter_ = 0;
if(output_mode_ == OutputMode::NTSC) is_odd_frame_ ^= true;
current_row_ = 0;
@ -399,6 +397,7 @@ template <class T> class MOS6560 {
registers_.invertedCells = !((value >> 3)&1);
registers_.borderColour = new_border_colour;
registers_.backgroundColour = colours_[value >> 4];
// printf("%d\n", horizontal_counter_);
}
break;
@ -452,12 +451,12 @@ template <class T> class MOS6560 {
unsigned int cycles_in_state_;
// counters that cover an entire field
int horizontal_counter_ = 0, vertical_counter_ = 0, full_frame_counter_;
int horizontal_counter_ = 0, vertical_counter_ = 0;
const int lines_this_field() {
return registers_.interlaced ? (is_odd_frame_ ? 262 : 263) : timing_.lines_per_progressive_field;
}
const int raster_value() {
return ((full_frame_counter_ + timing_.line_counter_increment_offset) / timing_.cycles_per_line) % lines_this_field();
return (vertical_counter_ + ((horizontal_counter_ + timing_.line_counter_increment_offset) / timing_.cycles_per_line)) % lines_this_field();
}
// latches dictating start and length of drawing