6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2025-01-11 08:30:55 +00:00
Code Issues Projects Releases Wiki Activity

Implements the ALTIND bits and attempts ATTR mode.

Browse Source
This commit is contained in:
Thomas Harte 2021-06-19 13:04:18 -04:00
parent 1651efe4fc
commit 1dcac304d3
2 changed files with 61 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
Machines/Enterprise/Nick.cpp
View File

@ -133,7 +133,7 @@ void Nick::run_for(Cycles duration) {
case Mode::CH128:
case Mode::CH256:
case Mode::LPixel: column_size_ = 8 / bpp_; break;
// case Mode::Attr: column_size_ = 8; break;
case Mode::Attr: column_size_ = 8; break;
}
// Act as if proper state transitions had occurred while HSYNC is being output.
@ -158,6 +158,16 @@ void Nick::run_for(Cycles duration) {
for(int c = 0; c < 8; c++) {
palette_[c] = mapped_colour(line_parameters_[8 + c]);
}
// Use ALTIND0 and ALTIND1 to pick the alt_ind_palettes.
//
// ALTIND1 = b6 of params[3], if set => character codes with bit 7 set should use palette indices 2 and 3.
// ALTIND0 = b7 of params[3], if set => character codes with bit 6 set should use palette indices 4... instead of 0... .
alt_ind_palettes[0] = palette_;
alt_ind_palettes[2] = alt_ind_palettes[0] + ((line_parameters_[3] & 0x40) ? 2 : 0);
alt_ind_palettes[1] = alt_ind_palettes[0] + ((line_parameters_[3] & 0x80) ? 4 : 0);
alt_ind_palettes[3] = alt_ind_palettes[2] + ((line_parameters_[3] & 0x80) ? 4 : 0);
}
}
@ -219,6 +229,7 @@ void Nick::run_for(Cycles duration) {
#define ch256(x) output_character<x, 8>
#define ch128(x) output_character<x, 7>
#define ch64(x) output_character<x, 6>
#define attr(x) output_attributed<x>
int columns_remaining = next_event - window;
while(columns_remaining) {
@ -237,6 +248,7 @@ void Nick::run_for(Cycles duration) {
case Mode::CH256: DispatchBpp(ch256); break;
case Mode::CH128: DispatchBpp(ch128); break;
case Mode::CH64: DispatchBpp(ch64); break;
case Mode::Attr: DispatchBpp(attr); break;
}
pixel_pointer_ += output_duration * column_size_;
@ -255,6 +267,7 @@ void Nick::run_for(Cycles duration) {
}
}
#undef attr
#undef ch64
#undef ch128
#undef ch256
@ -306,6 +319,13 @@ void Nick::run_for(Cycles duration) {
line_data_pointer_[0] = uint16_t(line_parameters_[4] | (line_parameters_[5] << 8));
++line_data_pointer_[1];
break;
case Mode::Attr:
// Reload the attribute address if VRES is set.
if(line_parameters_[1] & 0x10) {
line_data_pointer_[1] = uint16_t(line_parameters_[6] | (line_parameters_[7] << 8));
}
break;
}
}
}
@ -459,17 +479,45 @@ template <int bpp, int index_bits> void Nick::output_character(uint16_t *target,
assert(false);
break;
case 1:
target[0] = palette_[(pixels & 0x80) >> 7];
target[1] = palette_[(pixels & 0x40) >> 6];
target[2] = palette_[(pixels & 0x20) >> 5];
target[3] = palette_[(pixels & 0x10) >> 4];
target[4] = palette_[(pixels & 0x08) >> 3];
target[5] = palette_[(pixels & 0x04) >> 2];
target[6] = palette_[(pixels & 0x02) >> 1];
target[7] = palette_[(pixels & 0x01) >> 0];
case 1: {
// This applies ALTIND0 and ALTIND1.
const uint16_t *palette = alt_ind_palettes[character >> 6];
target[0] = palette[(pixels & 0x80) >> 7];
target[1] = palette[(pixels & 0x40) >> 6];
target[2] = palette[(pixels & 0x20) >> 5];
target[3] = palette[(pixels & 0x10) >> 4];
target[4] = palette[(pixels & 0x08) >> 3];
target[5] = palette[(pixels & 0x04) >> 2];
target[6] = palette[(pixels & 0x02) >> 1];
target[7] = palette[(pixels & 0x01) >> 0];
target += 8;
break;
} break;
}
}
}
template <int bpp> void Nick::output_attributed(uint16_t *target, int columns) {
static_assert(bpp == 1 || bpp == 2 || bpp == 4 || bpp == 8);
for(int c = 0; c < columns; c++) {
const uint8_t pixels = ram_[line_data_pointer_[0]];
const uint8_t attributes = ram_[line_data_pointer_[1]];
++line_data_pointer_[0];
++line_data_pointer_[1];
const uint16_t palette[2] = {
palette_[attributes >> 4], palette_[attributes & 0x0f]
};
target[0] = palette[(pixels & 0x80) >> 7];
target[1] = palette[(pixels & 0x40) >> 6];
target[2] = palette[(pixels & 0x20) >> 5];
target[3] = palette[(pixels & 0x10) >> 4];
target[4] = palette[(pixels & 0x08) >> 3];
target[5] = palette[(pixels & 0x04) >> 2];
target[6] = palette[(pixels & 0x02) >> 1];
target[7] = palette[(pixels & 0x01) >> 0];
target += 8;
}
}

2
Machines/Enterprise/Nick.hpp
View File

@ -56,6 +56,7 @@ class Nick {
// Current mode line parameters.
uint8_t lines_remaining_ = 0x00;
int left_margin_ = 0, right_margin_ = 0;
const uint16_t *alt_ind_palettes[4];
enum class Mode {
Vsync,
Pixel,
@ -93,6 +94,7 @@ class Nick {
// Specific outputters.
template <int bpp, bool is_lpixel> void output_pixel(uint16_t *target, int columns);
template <int bpp, int index_bits> void output_character(uint16_t *target, int columns);
template <int bpp> void output_attributed(uint16_t *target, int columns);
};