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frodo-wii/Src/VIC_SC.cpp

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/*
* VIC_SC.cpp - 6569R5 emulation (cycle based)
*
* Frodo (C) 1994-1997,2002-2005 Christian Bauer
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Incompatibilities:
* ------------------
*
* - Color of $ff bytes read when BA is low and AEC is high
* is not correct
* - Changes to border/background color are visible 7 pixels
* too late
* - Sprite data access doesn't respect BA
* - Sprite collisions are only detected within the visible
* screen area (excluding borders)
* - Sprites are only drawn if they completely fit within the
* left/right limits of the chunky bitmap
*/
#include "sysdeps.h"
#include "VIC.h"
#include "C64.h"
#include "CPUC64.h"
#include "Display.h"
#include "Prefs.h"
// First and last displayed line
const int FIRST_DISP_LINE = 0x10;
const int LAST_DISP_LINE = 0x11f;
// First and last possible line for Bad Lines
const int FIRST_DMA_LINE = 0x30;
const int LAST_DMA_LINE = 0xf7;
// Display window coordinates
const int ROW25_YSTART = 0x33;
const int ROW25_YSTOP = 0xfb;
const int ROW24_YSTART = 0x37;
const int ROW24_YSTOP = 0xf7;
#if defined(SMALL_DISPLAY)
/* This does not work yet, the sprite code doesn't know about it. */
const int COL40_XSTART = 0x14;
const int COL40_XSTOP = 0x154;
const int COL38_XSTART = 0x1B;
const int COL38_XSTOP = 0x14B;
#else
const int COL40_XSTART = 0x20;
const int COL40_XSTOP = 0x160;
const int COL38_XSTART = 0x27;
const int COL38_XSTOP = 0x157;
#endif
// Tables for sprite X expansion
uint16 ExpTable[256] = {
0x0000, 0x0003, 0x000C, 0x000F, 0x0030, 0x0033, 0x003C, 0x003F,
0x00C0, 0x00C3, 0x00CC, 0x00CF, 0x00F0, 0x00F3, 0x00FC, 0x00FF,
0x0300, 0x0303, 0x030C, 0x030F, 0x0330, 0x0333, 0x033C, 0x033F,
0x03C0, 0x03C3, 0x03CC, 0x03CF, 0x03F0, 0x03F3, 0x03FC, 0x03FF,
0x0C00, 0x0C03, 0x0C0C, 0x0C0F, 0x0C30, 0x0C33, 0x0C3C, 0x0C3F,
0x0CC0, 0x0CC3, 0x0CCC, 0x0CCF, 0x0CF0, 0x0CF3, 0x0CFC, 0x0CFF,
0x0F00, 0x0F03, 0x0F0C, 0x0F0F, 0x0F30, 0x0F33, 0x0F3C, 0x0F3F,
0x0FC0, 0x0FC3, 0x0FCC, 0x0FCF, 0x0FF0, 0x0FF3, 0x0FFC, 0x0FFF,
0x3000, 0x3003, 0x300C, 0x300F, 0x3030, 0x3033, 0x303C, 0x303F,
0x30C0, 0x30C3, 0x30CC, 0x30CF, 0x30F0, 0x30F3, 0x30FC, 0x30FF,
0x3300, 0x3303, 0x330C, 0x330F, 0x3330, 0x3333, 0x333C, 0x333F,
0x33C0, 0x33C3, 0x33CC, 0x33CF, 0x33F0, 0x33F3, 0x33FC, 0x33FF,
0x3C00, 0x3C03, 0x3C0C, 0x3C0F, 0x3C30, 0x3C33, 0x3C3C, 0x3C3F,
0x3CC0, 0x3CC3, 0x3CCC, 0x3CCF, 0x3CF0, 0x3CF3, 0x3CFC, 0x3CFF,
0x3F00, 0x3F03, 0x3F0C, 0x3F0F, 0x3F30, 0x3F33, 0x3F3C, 0x3F3F,
0x3FC0, 0x3FC3, 0x3FCC, 0x3FCF, 0x3FF0, 0x3FF3, 0x3FFC, 0x3FFF,
0xC000, 0xC003, 0xC00C, 0xC00F, 0xC030, 0xC033, 0xC03C, 0xC03F,
0xC0C0, 0xC0C3, 0xC0CC, 0xC0CF, 0xC0F0, 0xC0F3, 0xC0FC, 0xC0FF,
0xC300, 0xC303, 0xC30C, 0xC30F, 0xC330, 0xC333, 0xC33C, 0xC33F,
0xC3C0, 0xC3C3, 0xC3CC, 0xC3CF, 0xC3F0, 0xC3F3, 0xC3FC, 0xC3FF,
0xCC00, 0xCC03, 0xCC0C, 0xCC0F, 0xCC30, 0xCC33, 0xCC3C, 0xCC3F,
0xCCC0, 0xCCC3, 0xCCCC, 0xCCCF, 0xCCF0, 0xCCF3, 0xCCFC, 0xCCFF,
0xCF00, 0xCF03, 0xCF0C, 0xCF0F, 0xCF30, 0xCF33, 0xCF3C, 0xCF3F,
0xCFC0, 0xCFC3, 0xCFCC, 0xCFCF, 0xCFF0, 0xCFF3, 0xCFFC, 0xCFFF,
0xF000, 0xF003, 0xF00C, 0xF00F, 0xF030, 0xF033, 0xF03C, 0xF03F,
0xF0C0, 0xF0C3, 0xF0CC, 0xF0CF, 0xF0F0, 0xF0F3, 0xF0FC, 0xF0FF,
0xF300, 0xF303, 0xF30C, 0xF30F, 0xF330, 0xF333, 0xF33C, 0xF33F,
0xF3C0, 0xF3C3, 0xF3CC, 0xF3CF, 0xF3F0, 0xF3F3, 0xF3FC, 0xF3FF,
0xFC00, 0xFC03, 0xFC0C, 0xFC0F, 0xFC30, 0xFC33, 0xFC3C, 0xFC3F,
0xFCC0, 0xFCC3, 0xFCCC, 0xFCCF, 0xFCF0, 0xFCF3, 0xFCFC, 0xFCFF,
0xFF00, 0xFF03, 0xFF0C, 0xFF0F, 0xFF30, 0xFF33, 0xFF3C, 0xFF3F,
0xFFC0, 0xFFC3, 0xFFCC, 0xFFCF, 0xFFF0, 0xFFF3, 0xFFFC, 0xFFFF
};
uint16 MultiExpTable[256] = {
0x0000, 0x0005, 0x000A, 0x000F, 0x0050, 0x0055, 0x005A, 0x005F,
0x00A0, 0x00A5, 0x00AA, 0x00AF, 0x00F0, 0x00F5, 0x00FA, 0x00FF,
0x0500, 0x0505, 0x050A, 0x050F, 0x0550, 0x0555, 0x055A, 0x055F,
0x05A0, 0x05A5, 0x05AA, 0x05AF, 0x05F0, 0x05F5, 0x05FA, 0x05FF,
0x0A00, 0x0A05, 0x0A0A, 0x0A0F, 0x0A50, 0x0A55, 0x0A5A, 0x0A5F,
0x0AA0, 0x0AA5, 0x0AAA, 0x0AAF, 0x0AF0, 0x0AF5, 0x0AFA, 0x0AFF,
0x0F00, 0x0F05, 0x0F0A, 0x0F0F, 0x0F50, 0x0F55, 0x0F5A, 0x0F5F,
0x0FA0, 0x0FA5, 0x0FAA, 0x0FAF, 0x0FF0, 0x0FF5, 0x0FFA, 0x0FFF,
0x5000, 0x5005, 0x500A, 0x500F, 0x5050, 0x5055, 0x505A, 0x505F,
0x50A0, 0x50A5, 0x50AA, 0x50AF, 0x50F0, 0x50F5, 0x50FA, 0x50FF,
0x5500, 0x5505, 0x550A, 0x550F, 0x5550, 0x5555, 0x555A, 0x555F,
0x55A0, 0x55A5, 0x55AA, 0x55AF, 0x55F0, 0x55F5, 0x55FA, 0x55FF,
0x5A00, 0x5A05, 0x5A0A, 0x5A0F, 0x5A50, 0x5A55, 0x5A5A, 0x5A5F,
0x5AA0, 0x5AA5, 0x5AAA, 0x5AAF, 0x5AF0, 0x5AF5, 0x5AFA, 0x5AFF,
0x5F00, 0x5F05, 0x5F0A, 0x5F0F, 0x5F50, 0x5F55, 0x5F5A, 0x5F5F,
0x5FA0, 0x5FA5, 0x5FAA, 0x5FAF, 0x5FF0, 0x5FF5, 0x5FFA, 0x5FFF,
0xA000, 0xA005, 0xA00A, 0xA00F, 0xA050, 0xA055, 0xA05A, 0xA05F,
0xA0A0, 0xA0A5, 0xA0AA, 0xA0AF, 0xA0F0, 0xA0F5, 0xA0FA, 0xA0FF,
0xA500, 0xA505, 0xA50A, 0xA50F, 0xA550, 0xA555, 0xA55A, 0xA55F,
0xA5A0, 0xA5A5, 0xA5AA, 0xA5AF, 0xA5F0, 0xA5F5, 0xA5FA, 0xA5FF,
0xAA00, 0xAA05, 0xAA0A, 0xAA0F, 0xAA50, 0xAA55, 0xAA5A, 0xAA5F,
0xAAA0, 0xAAA5, 0xAAAA, 0xAAAF, 0xAAF0, 0xAAF5, 0xAAFA, 0xAAFF,
0xAF00, 0xAF05, 0xAF0A, 0xAF0F, 0xAF50, 0xAF55, 0xAF5A, 0xAF5F,
0xAFA0, 0xAFA5, 0xAFAA, 0xAFAF, 0xAFF0, 0xAFF5, 0xAFFA, 0xAFFF,
0xF000, 0xF005, 0xF00A, 0xF00F, 0xF050, 0xF055, 0xF05A, 0xF05F,
0xF0A0, 0xF0A5, 0xF0AA, 0xF0AF, 0xF0F0, 0xF0F5, 0xF0FA, 0xF0FF,
0xF500, 0xF505, 0xF50A, 0xF50F, 0xF550, 0xF555, 0xF55A, 0xF55F,
0xF5A0, 0xF5A5, 0xF5AA, 0xF5AF, 0xF5F0, 0xF5F5, 0xF5FA, 0xF5FF,
0xFA00, 0xFA05, 0xFA0A, 0xFA0F, 0xFA50, 0xFA55, 0xFA5A, 0xFA5F,
0xFAA0, 0xFAA5, 0xFAAA, 0xFAAF, 0xFAF0, 0xFAF5, 0xFAFA, 0xFAFF,
0xFF00, 0xFF05, 0xFF0A, 0xFF0F, 0xFF50, 0xFF55, 0xFF5A, 0xFF5F,
0xFFA0, 0xFFA5, 0xFFAA, 0xFFAF, 0xFFF0, 0xFFF5, 0xFFFA, 0xFFFF
};
/*
* Constructor: Initialize variables
*/
MOS6569::MOS6569(C64 *c64, C64Display *disp, MOS6510 *CPU, uint8 *RAM, uint8 *Char, uint8 *Color)
: ram(RAM), char_rom(Char), color_ram(Color), the_c64(c64), the_display(disp), the_cpu(CPU)
{
int i;
is_bad_line = false;
spr_exp_y = 0;
memset(mc_base, 0, sizeof(mc_base));
// Set pointers
matrix_base = 0;
char_base = 0;
bitmap_base = 0;
// Get bitmap info
chunky_ptr = chunky_line_start = disp->BitmapBase();
xmod = disp->BitmapXMod();
// Initialize VIC registers
mx8 = 0;
ctrl1 = ctrl2 = 0;
lpx = lpy = 0;
me = mxe = mye = mdp = mmc = 0;
vbase = irq_flag = irq_mask = 0;
clx_spr = clx_bgr = 0;
cia_vabase = 0;
ec = b0c = b1c = b2c = b3c = mm0 = mm1 = 0;
for (i=0; i<8; i++) mx[i] = my[i] = sc[i] = 0;
// Initialize other variables
raster_y = TOTAL_RASTERS - 1;
rc = 7;
irq_raster = vc = vc_base = x_scroll = y_scroll = 0;
dy_start = ROW24_YSTART;
dy_stop = ROW24_YSTOP;
ml_index = 0;
cycle = 1;
display_idx = 0;
display_state = false;
border_on = ud_border_on = vblanking = false;
lp_triggered = draw_this_line = false;
spr_dma_on = spr_disp_on = 0;
for (i=0; i<8; i++) {
mc[i] = 63;
spr_ptr[i] = 0;
}
frame_skipped = false;
skip_counter = 1;
memset(spr_coll_buf, 0, 0x180);
memset(fore_mask_buf, 0, 0x180/8);
// Preset colors to black
disp->InitColors(colors);
ec_color = b0c_color = b1c_color = b2c_color = b3c_color = mm0_color = mm1_color = colors[0];
for (i=0; i<8; i++) spr_color[i] = colors[0];
}
/*
* Reinitialize the colors table for when the palette has changed
*/
void MOS6569::ReInitColors(void)
{
int i;
// Build inverse color table.
uint8 xlate_colors[256];
memset(xlate_colors, 0, sizeof(xlate_colors));
for (i=0; i<16; i++)
xlate_colors[colors[i]] = i;
// Get the new colors.
the_display->InitColors(colors);
// Build color translation table.
for (i=0; i<256; i++)
xlate_colors[i] = colors[xlate_colors[i]];
// Translate all the old colors variables.
ec_color = colors[ec];
b0c_color = colors[b0c];
b1c_color = colors[b1c];
b2c_color = colors[b2c];
b3c_color = colors[b3c];
mm0_color = colors[mm0];
mm1_color = colors[mm1];
for (i=0; i<8; i++)
spr_color[i] = colors[sc[i]];
// Translate the border color sample buffer.
for (unsigned x = 0; x < sizeof(border_color_sample); x++)
border_color_sample[x] = xlate_colors[border_color_sample[x]];
// Translate the chunky buffer.
uint8 *scanline = the_display->BitmapBase();
for (int y=0; y<DISPLAY_Y; y++) {
for (int x=0; x<DISPLAY_X; x++)
scanline[x] = xlate_colors[scanline[x]];
scanline += xmod;
}
}
/*
* Get VIC state
*/
void MOS6569::GetState(MOS6569State *vd)
{
int i;
vd->m0x = mx[0] & 0xff; vd->m0y = my[0];
vd->m1x = mx[1] & 0xff; vd->m1y = my[1];
vd->m2x = mx[2] & 0xff; vd->m2y = my[2];
vd->m3x = mx[3] & 0xff; vd->m3y = my[3];
vd->m4x = mx[4] & 0xff; vd->m4y = my[4];
vd->m5x = mx[5] & 0xff; vd->m5y = my[5];
vd->m6x = mx[6] & 0xff; vd->m6y = my[6];
vd->m7x = mx[7] & 0xff; vd->m7y = my[7];
vd->mx8 = mx8;
vd->ctrl1 = (ctrl1 & 0x7f) | ((raster_y & 0x100) >> 1);
vd->raster = raster_y & 0xff;
vd->lpx = lpx; vd->lpy = lpy;
vd->ctrl2 = ctrl2;
vd->vbase = vbase;
vd->irq_flag = irq_flag;
vd->irq_mask = irq_mask;
vd->me = me; vd->mxe = mxe; vd->mye = mye; vd->mdp = mdp; vd->mmc = mmc;
vd->mm = clx_spr; vd->md = clx_bgr;
vd->ec = ec;
vd->b0c = b0c; vd->b1c = b1c; vd->b2c = b2c; vd->b3c = b3c;
vd->mm0 = mm0; vd->mm1 = mm1;
vd->m0c = sc[0];
vd->m1c = sc[1];
vd->m2c = sc[2];
vd->m3c = sc[3];
vd->m4c = sc[4];
vd->m5c = sc[5];
vd->m6c = sc[6];
vd->m7c = sc[7];
vd->pad0 = 0;
vd->irq_raster = irq_raster;
vd->vc = vc;
vd->vc_base = vc_base;
vd->rc = rc;
vd->spr_dma = spr_dma_on;
vd->spr_disp = spr_disp_on;
for (i=0; i<8; i++) {
vd->mc[i] = mc[i];
vd->mc_base[i] = mc_base[i];
}
vd->display_state = display_state;
vd->bad_line = raster_y >= FIRST_DMA_LINE && raster_y <= LAST_DMA_LINE && ((raster_y & 7) == y_scroll) && bad_lines_enabled;
vd->bad_line_enable = bad_lines_enabled;
vd->lp_triggered = lp_triggered;
vd->border_on = border_on;
vd->bank_base = cia_vabase;
vd->matrix_base = ((vbase & 0xf0) << 6) | cia_vabase;
vd->char_base = ((vbase & 0x0e) << 10) | cia_vabase;
vd->bitmap_base = ((vbase & 0x08) << 10) | cia_vabase;
for (i=0; i<8; i++)
vd->sprite_base[i] = spr_ptr[i] | cia_vabase;
vd->cycle = cycle;
vd->raster_x = raster_x;
vd->ml_index = ml_index;
vd->ref_cnt = ref_cnt;
vd->last_vic_byte = LastVICByte;
vd->ud_border_on = ud_border_on;
}
/*
* Set VIC state (only works if in VBlank)
*/
void MOS6569::SetState(MOS6569State *vd)
{
int i, j;
mx[0] = vd->m0x; my[0] = vd->m0y;
mx[1] = vd->m1x; my[1] = vd->m1y;
mx[2] = vd->m2x; my[2] = vd->m2y;
mx[3] = vd->m3x; my[3] = vd->m3y;
mx[4] = vd->m4x; my[4] = vd->m4y;
mx[5] = vd->m5x; my[5] = vd->m5y;
mx[6] = vd->m6x; my[6] = vd->m6y;
mx[7] = vd->m7x; my[7] = vd->m7y;
mx8 = vd->mx8;
for (i=0, j=1; i<8; i++, j<<=1) {
if (mx8 & j)
mx[i] |= 0x100;
else
mx[i] &= 0xff;
}
ctrl1 = vd->ctrl1;
ctrl2 = vd->ctrl2;
x_scroll = ctrl2 & 7;
y_scroll = ctrl1 & 7;
if (ctrl1 & 8) {
dy_start = ROW25_YSTART;
dy_stop = ROW25_YSTOP;
} else {
dy_start = ROW24_YSTART;
dy_stop = ROW24_YSTOP;
}
display_idx = ((ctrl1 & 0x60) | (ctrl2 & 0x10)) >> 4;
raster_y = 0;
lpx = vd->lpx; lpy = vd->lpy;
vbase = vd->vbase;
cia_vabase = vd->bank_base;
matrix_base = (vbase & 0xf0) << 6;
char_base = (vbase & 0x0e) << 10;
bitmap_base = (vbase & 0x08) << 10;
irq_flag = vd->irq_flag;
irq_mask = vd->irq_mask;
me = vd->me; mxe = vd->mxe; mye = vd->mye; mdp = vd->mdp; mmc = vd->mmc;
clx_spr = vd->mm; clx_bgr = vd->md;
ec = vd->ec;
ec_color = colors[ec];
b0c = vd->b0c; b1c = vd->b1c; b2c = vd->b2c; b3c = vd->b3c;
b0c_color = colors[b0c];
b1c_color = colors[b1c];
b2c_color = colors[b2c];
b3c_color = colors[b3c];
mm0 = vd->mm0; mm1 = vd->mm1;
mm0_color = colors[mm0];
mm1_color = colors[mm1];
sc[0] = vd->m0c; sc[1] = vd->m1c;
sc[2] = vd->m2c; sc[3] = vd->m3c;
sc[4] = vd->m4c; sc[5] = vd->m5c;
sc[6] = vd->m6c; sc[7] = vd->m7c;
for (i=0; i<8; i++)
spr_color[i] = colors[sc[i]];
irq_raster = vd->irq_raster;
vc = vd->vc;
vc_base = vd->vc_base;
rc = vd->rc;
spr_dma_on = vd->spr_dma;
spr_disp_on = vd->spr_disp;
for (i=0; i<8; i++) {
mc[i] = vd->mc[i];
mc_base[i] = vd->mc_base[i];
spr_ptr[i] = vd->sprite_base[i] & 0x3fff;
}
display_state = vd->display_state;
bad_lines_enabled = vd->bad_line_enable;
lp_triggered = vd->lp_triggered;
border_on = vd->border_on;
cycle = vd->cycle;
raster_x = vd->raster_x;
ml_index = vd->ml_index;
ref_cnt = vd->ref_cnt;
LastVICByte = vd->last_vic_byte;
ud_border_on = vd->ud_border_on;
}
/*
* Trigger raster IRQ
*/
inline void MOS6569::raster_irq(void)
{
irq_flag |= 0x01;
if (irq_mask & 0x01) {
irq_flag |= 0x80;
the_cpu->TriggerVICIRQ();
}
}
/*
* Read from VIC register
*/
uint8 MOS6569::ReadRegister(uint16 adr)
{
switch (adr) {
case 0x00: case 0x02: case 0x04: case 0x06:
case 0x08: case 0x0a: case 0x0c: case 0x0e:
return mx[adr >> 1];
case 0x01: case 0x03: case 0x05: case 0x07:
case 0x09: case 0x0b: case 0x0d: case 0x0f:
return my[adr >> 1];
case 0x10: // Sprite X position MSB
return mx8;
case 0x11: // Control register 1
return (ctrl1 & 0x7f) | ((raster_y & 0x100) >> 1);
case 0x12: // Raster counter
return raster_y;
case 0x13: // Light pen X
return lpx;
case 0x14: // Light pen Y
return lpy;
case 0x15: // Sprite enable
return me;
case 0x16: // Control register 2
return ctrl2 | 0xc0;
case 0x17: // Sprite Y expansion
return mye;
case 0x18: // Memory pointers
return vbase | 0x01;
case 0x19: // IRQ flags
return irq_flag | 0x70;
case 0x1a: // IRQ mask
return irq_mask | 0xf0;
case 0x1b: // Sprite data priority
return mdp;
case 0x1c: // Sprite multicolor
return mmc;
case 0x1d: // Sprite X expansion
return mxe;
case 0x1e:{ // Sprite-sprite collision
uint8 ret = clx_spr;
clx_spr = 0; // Read and clear
return ret;
}
case 0x1f:{ // Sprite-background collision
uint8 ret = clx_bgr;
clx_bgr = 0; // Read and clear
return ret;
}
case 0x20: return ec | 0xf0;
case 0x21: return b0c | 0xf0;
case 0x22: return b1c | 0xf0;
case 0x23: return b2c | 0xf0;
case 0x24: return b3c | 0xf0;
case 0x25: return mm0 | 0xf0;
case 0x26: return mm1 | 0xf0;
case 0x27: case 0x28: case 0x29: case 0x2a:
case 0x2b: case 0x2c: case 0x2d: case 0x2e:
return sc[adr - 0x27] | 0xf0;
default:
return 0xff;
}
}
/*
* Write to VIC register
*/
void MOS6569::WriteRegister(uint16 adr, uint8 byte)
{
switch (adr) {
case 0x00: case 0x02: case 0x04: case 0x06:
case 0x08: case 0x0a: case 0x0c: case 0x0e:
mx[adr >> 1] = (mx[adr >> 1] & 0xff00) | byte;
break;
case 0x10:{
int i, j;
mx8 = byte;
for (i=0, j=1; i<8; i++, j<<=1) {
if (mx8 & j)
mx[i] |= 0x100;
else
mx[i] &= 0xff;
}
break;
}
case 0x01: case 0x03: case 0x05: case 0x07:
case 0x09: case 0x0b: case 0x0d: case 0x0f:
my[adr >> 1] = byte;
break;
case 0x11:{ // Control register 1
ctrl1 = byte;
y_scroll = byte & 7;
uint16 new_irq_raster = (irq_raster & 0xff) | ((byte & 0x80) << 1);
if (irq_raster != new_irq_raster && raster_y == new_irq_raster)
raster_irq();
irq_raster = new_irq_raster;
if (byte & 8) {
dy_start = ROW25_YSTART;
dy_stop = ROW25_YSTOP;
} else {
dy_start = ROW24_YSTART;
dy_stop = ROW24_YSTOP;
}
// In line $30, the DEN bit controls if Bad Lines can occur
if (raster_y == 0x30 && byte & 0x10)
bad_lines_enabled = true;
// Bad Line condition?
is_bad_line = (raster_y >= FIRST_DMA_LINE && raster_y <= LAST_DMA_LINE && ((raster_y & 7) == y_scroll) && bad_lines_enabled);
display_idx = ((ctrl1 & 0x60) | (ctrl2 & 0x10)) >> 4;
break;
}
case 0x12:{ // Raster counter
uint16 new_irq_raster = (irq_raster & 0xff00) | byte;
if (irq_raster != new_irq_raster && raster_y == new_irq_raster)
raster_irq();
irq_raster = new_irq_raster;
break;
}
case 0x15: // Sprite enable
me = byte;
break;
case 0x16: // Control register 2
ctrl2 = byte;
x_scroll = byte & 7;
display_idx = ((ctrl1 & 0x60) | (ctrl2 & 0x10)) >> 4;
break;
case 0x17: // Sprite Y expansion
mye = byte;
spr_exp_y |= ~byte;
break;
case 0x18: // Memory pointers
vbase = byte;
matrix_base = (byte & 0xf0) << 6;
char_base = (byte & 0x0e) << 10;
bitmap_base = (byte & 0x08) << 10;
break;
case 0x19: // IRQ flags
irq_flag = irq_flag & (~byte & 0x0f);
if (irq_flag & irq_mask) // Set master bit if allowed interrupt still pending
irq_flag |= 0x80;
else
the_cpu->ClearVICIRQ(); // Else clear interrupt
break;
case 0x1a: // IRQ mask
irq_mask = byte & 0x0f;
if (irq_flag & irq_mask) { // Trigger interrupt if pending and now allowed
irq_flag |= 0x80;
the_cpu->TriggerVICIRQ();
} else {
irq_flag &= 0x7f;
the_cpu->ClearVICIRQ();
}
break;
case 0x1b: // Sprite data priority
mdp = byte;
break;
case 0x1c: // Sprite multicolor
mmc = byte;
break;
case 0x1d: // Sprite X expansion
mxe = byte;
break;
case 0x20: ec_color = colors[ec = byte]; break;
case 0x21: b0c_color = colors[b0c = byte]; break;
case 0x22: b1c_color = colors[b1c = byte]; break;
case 0x23: b2c_color = colors[b2c = byte]; break;
case 0x24: b3c_color = colors[b3c = byte]; break;
case 0x25: mm0_color = colors[mm0 = byte]; break;
case 0x26: mm1_color = colors[mm1 = byte]; break;
case 0x27: case 0x28: case 0x29: case 0x2a:
case 0x2b: case 0x2c: case 0x2d: case 0x2e:
spr_color[adr - 0x27] = colors[sc[adr - 0x27] = byte];
break;
}
}
/*
* CIA VA14/15 has changed
*/
void MOS6569::ChangedVA(uint16 new_va)
{
cia_vabase = new_va << 14;
WriteRegister(0x18, vbase); // Force update of memory pointers
}
/*
* Trigger lightpen interrupt, latch lightpen coordinates
*/
void MOS6569::TriggerLightpen(void)
{
if (!lp_triggered) { // Lightpen triggers only once per frame
lp_triggered = true;
lpx = raster_x >> 1; // Latch current coordinates
lpy = raster_y;
irq_flag |= 0x08; // Trigger IRQ
if (irq_mask & 0x08) {
irq_flag |= 0x80;
the_cpu->TriggerVICIRQ();
}
}
}
/*
* Read a byte from the VIC's address space
*/
inline uint8 MOS6569::read_byte(uint16 adr)
{
uint16 va = adr | cia_vabase;
if ((va & 0x7000) == 0x1000)
return LastVICByte = char_rom[va & 0x0fff];
else
return LastVICByte = ram[va];
}
/*
* Quick memset of 8 bytes
*/
inline void memset8(uint8 *p, uint8 c)
{
p[0] = p[1] = p[2] = p[3] = p[4] = p[5] = p[6] = p[7] = c;
}
/*
* Video matrix access
*/
void MOS6569::matrix_access(void)
{
if (the_cpu->BALow) {
if (the_c64->CycleCounter-first_ba_cycle < 3)
matrix_line[ml_index] = color_line[ml_index] = 0xff;
else {
uint16 adr = (vc & 0x03ff) | matrix_base;
matrix_line[ml_index] = read_byte(adr);
color_line[ml_index] = color_ram[adr & 0x03ff];
}
}
}
/*
* Graphics data access
*/
void MOS6569::graphics_access(void)
{
if (display_state) {
uint16 adr;
if (ctrl1 & 0x20) // Bitmap
adr = ((vc & 0x03ff) << 3) | bitmap_base | rc;
else // Text
adr = (matrix_line[ml_index] << 3) | char_base | rc;
if (ctrl1 & 0x40) // ECM
adr &= 0xf9ff;
gfx_data = read_byte(adr);
char_data = matrix_line[ml_index];
color_data = color_line[ml_index];
ml_index++;
vc++;
} else {
// Display is off
gfx_data = read_byte(ctrl1 & 0x40 ? 0x39ff : 0x3fff);
char_data = color_data = 0;
}
}
/*
* Background display (8 pixels)
*/
void MOS6569::draw_background(void)
{
uint8 *p = chunky_ptr;
uint8 c;
if (!draw_this_line)
return;
switch (display_idx) {
case 0: // Standard text
case 1: // Multicolor text
case 3: // Multicolor bitmap
c = b0c_color;
break;
case 2: // Standard bitmap
c = colors[last_char_data];
break;
case 4: // ECM text
if (last_char_data & 0x80)
if (last_char_data & 0x40)
c = b3c_color;
else
c = b2c_color;
else
if (last_char_data & 0x40)
c = b1c_color;
else
c = b0c_color;
break;
default:
c = colors[0];
break;
}
memset8(p, c);
}
/*
* Graphics display (8 pixels)
*/
void MOS6569::draw_graphics(void)
{
uint8 *p = chunky_ptr + x_scroll;
uint8 c[4], data;
if (!draw_this_line)
return;
if (ud_border_on) {
draw_background();
return;
}
switch (display_idx) {
case 0: // Standard text
c[0] = b0c_color;
c[1] = colors[color_data];
goto draw_std;
case 1: // Multicolor text
if (color_data & 8) {
c[0] = b0c_color;
c[1] = b1c_color;
c[2] = b2c_color;
c[3] = colors[color_data & 7];
goto draw_multi;
} else {
c[0] = b0c_color;
c[1] = colors[color_data];
goto draw_std;
}
case 2: // Standard bitmap
c[0] = colors[char_data];
c[1] = colors[char_data >> 4];
goto draw_std;
case 3: // Multicolor bitmap
c[0]= b0c_color;
c[1] = colors[char_data >> 4];
c[2] = colors[char_data];
c[3] = colors[color_data];
goto draw_multi;
case 4: // ECM text
if (char_data & 0x80)
if (char_data & 0x40)
c[0] = b3c_color;
else
c[0] = b2c_color;
else
if (char_data & 0x40)
c[0] = b1c_color;
else
c[0] = b0c_color;
c[1] = colors[color_data];
goto draw_std;
case 5: // Invalid multicolor text
memset8(p, colors[0]);
if (color_data & 8) {
fore_mask_ptr[0] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) >> x_scroll;
fore_mask_ptr[1] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) << (8-x_scroll);
} else {
fore_mask_ptr[0] |= gfx_data >> x_scroll;
fore_mask_ptr[1] |= gfx_data << (7-x_scroll);
}
return;
case 6: // Invalid standard bitmap
memset8(p, colors[0]);
fore_mask_ptr[0] |= gfx_data >> x_scroll;
fore_mask_ptr[1] |= gfx_data << (7-x_scroll);
return;
case 7: // Invalid multicolor bitmap
memset8(p, colors[0]);
fore_mask_ptr[0] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) >> x_scroll;
fore_mask_ptr[1] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) << (8-x_scroll);
return;
default: // Can't happen
return;
}
draw_std:
fore_mask_ptr[0] |= gfx_data >> x_scroll;
fore_mask_ptr[1] |= gfx_data << (7-x_scroll);
data = gfx_data;
p[7] = c[data & 1]; data >>= 1;
p[6] = c[data & 1]; data >>= 1;
p[5] = c[data & 1]; data >>= 1;
p[4] = c[data & 1]; data >>= 1;
p[3] = c[data & 1]; data >>= 1;
p[2] = c[data & 1]; data >>= 1;
p[1] = c[data & 1]; data >>= 1;
p[0] = c[data];
return;
draw_multi:
fore_mask_ptr[0] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) >> x_scroll;
fore_mask_ptr[1] |= ((gfx_data & 0xaa) | (gfx_data & 0xaa) >> 1) << (8-x_scroll);
data = gfx_data;
p[7] = p[6] = c[data & 3]; data >>= 2;
p[5] = p[4] = c[data & 3]; data >>= 2;
p[3] = p[2] = c[data & 3]; data >>= 2;
p[1] = p[0] = c[data];
return;
}
/*
* Sprite display
*/
inline void MOS6569::draw_sprites(void)
{
int i;
int snum, sbit; // Sprite number/bit mask
int spr_coll=0, gfx_coll=0;
// Clear sprite collision buffer
{
uint32 *lp = (uint32 *)spr_coll_buf - 1;
for (i=0; i<DISPLAY_X/4; i++)
*++lp = 0;
}
// Loop for all sprites
for (snum=0, sbit=1; snum<8; snum++, sbit<<=1) {
// Is sprite visible?
if ((spr_draw & sbit) && mx[snum] <= DISPLAY_X-32) {
#ifdef __POWERPC__
uint8 *p = (uint8 *)chunky_tmp + mx[snum] + 8;
#else
uint8 *p = chunky_line_start + mx[snum] + 8;
#endif
uint8 *q = spr_coll_buf + mx[snum] + 8;
uint8 color = spr_color[snum];
// Fetch sprite data and mask
uint32 sdata = (spr_draw_data[snum][0] << 24) | (spr_draw_data[snum][1] << 16) | (spr_draw_data[snum][2] << 8);
int spr_mask_pos = mx[snum] + 8; // Sprite bit position in fore_mask_buf
uint8 *fmbp = fore_mask_buf + (spr_mask_pos / 8);
int sshift = spr_mask_pos & 7;
uint32 fore_mask = (((*(fmbp+0) << 24) | (*(fmbp+1) << 16) | (*(fmbp+2) << 8)
| (*(fmbp+3))) << sshift) | (*(fmbp+4) >> (8-sshift));
if (mxe & sbit) { // X-expanded
if (mx[snum] > DISPLAY_X-56)
continue;
uint32 sdata_l = 0, sdata_r = 0, fore_mask_r;
fore_mask_r = (((*(fmbp+4) << 24) | (*(fmbp+5) << 16) | (*(fmbp+6) << 8)
| (*(fmbp+7))) << sshift) | (*(fmbp+8) >> (8-sshift));
if (mmc & sbit) { // Multicolor mode
uint32 plane0_l, plane0_r, plane1_l, plane1_r;
// Expand sprite data
sdata_l = MultiExpTable[sdata >> 24 & 0xff] << 16 | MultiExpTable[sdata >> 16 & 0xff];
sdata_r = MultiExpTable[sdata >> 8 & 0xff] << 16;
// Convert sprite chunky pixels to bitplanes
plane0_l = (sdata_l & 0x55555555) | (sdata_l & 0x55555555) << 1;
plane1_l = (sdata_l & 0xaaaaaaaa) | (sdata_l & 0xaaaaaaaa) >> 1;
plane0_r = (sdata_r & 0x55555555) | (sdata_r & 0x55555555) << 1;
plane1_r = (sdata_r & 0xaaaaaaaa) | (sdata_r & 0xaaaaaaaa) >> 1;
// Collision with graphics?
if ((fore_mask & (plane0_l | plane1_l)) || (fore_mask_r & (plane0_r | plane1_r))) {
gfx_coll |= sbit;
if (mdp & sbit) {
plane0_l &= ~fore_mask; // Mask sprite if in background
plane1_l &= ~fore_mask;
plane0_r &= ~fore_mask_r;
plane1_r &= ~fore_mask_r;
}
}
// Paint sprite
for (i=0; i<32; i++, plane0_l<<=1, plane1_l<<=1) {
uint8 col;
if (plane1_l & 0x80000000) {
if (plane0_l & 0x80000000)
col = mm1_color;
else
col = color;
} else {
if (plane0_l & 0x80000000)
col = mm0_color;
else
continue;
}
if (q[i])
spr_coll |= q[i] | sbit;
else {
p[i] = col;
q[i] = sbit;
}
}
for (; i<48; i++, plane0_r<<=1, plane1_r<<=1) {
uint8 col;
if (plane1_r & 0x80000000) {
if (plane0_r & 0x80000000)
col = mm1_color;
else
col = color;
} else {
if (plane0_r & 0x80000000)
col = mm0_color;
else
continue;
}
if (q[i])
spr_coll |= q[i] | sbit;
else {
p[i] = col;
q[i] = sbit;
}
}
} else { // Standard mode
// Expand sprite data
sdata_l = ExpTable[sdata >> 24 & 0xff] << 16 | ExpTable[sdata >> 16 & 0xff];
sdata_r = ExpTable[sdata >> 8 & 0xff] << 16;
// Collision with graphics?
if ((fore_mask & sdata_l) || (fore_mask_r & sdata_r)) {
gfx_coll |= sbit;
if (mdp & sbit) {
sdata_l &= ~fore_mask; // Mask sprite if in background
sdata_r &= ~fore_mask_r;
}
}
// Paint sprite
for (i=0; i<32; i++, sdata_l<<=1)
if (sdata_l & 0x80000000) {
if (q[i]) // Collision with sprite?
spr_coll |= q[i] | sbit;
else { // Draw pixel if no collision
p[i] = color;
q[i] = sbit;
}
}
for (; i<48; i++, sdata_r<<=1)
if (sdata_r & 0x80000000) {
if (q[i]) // Collision with sprite?
spr_coll |= q[i] | sbit;
else { // Draw pixel if no collision
p[i] = color;
q[i] = sbit;
}
}
}
} else { // Unexpanded
if (mmc & sbit) { // Multicolor mode
uint32 plane0, plane1;
// Convert sprite chunky pixels to bitplanes
plane0 = (sdata & 0x55555555) | (sdata & 0x55555555) << 1;
plane1 = (sdata & 0xaaaaaaaa) | (sdata & 0xaaaaaaaa) >> 1;
// Collision with graphics?
if (fore_mask & (plane0 | plane1)) {
gfx_coll |= sbit;
if (mdp & sbit) {
plane0 &= ~fore_mask; // Mask sprite if in background
plane1 &= ~fore_mask;
}
}
// Paint sprite
for (i=0; i<24; i++, plane0<<=1, plane1<<=1) {
uint8 col;
if (plane1 & 0x80000000) {
if (plane0 & 0x80000000)
col = mm1_color;
else
col = color;
} else {
if (plane0 & 0x80000000)
col = mm0_color;
else
continue;
}
if (q[i])
spr_coll |= q[i] | sbit;
else {
p[i] = col;
q[i] = sbit;
}
}
} else { // Standard mode
// Collision with graphics?
if (fore_mask & sdata) {
gfx_coll |= sbit;
if (mdp & sbit)
sdata &= ~fore_mask; // Mask sprite if in background
}
// Paint sprite
for (i=0; i<24; i++, sdata<<=1)
if (sdata & 0x80000000) {
if (q[i]) { // Collision with sprite?
spr_coll |= q[i] | sbit;
} else { // Draw pixel if no collision
p[i] = color;
q[i] = sbit;
}
}
}
}
}
}
if (ThePrefs.SpriteCollisions) {
// Check sprite-sprite collisions
if (clx_spr)
clx_spr |= spr_coll;
else {
clx_spr |= spr_coll;
irq_flag |= 0x04;
if (irq_mask & 0x04) {
irq_flag |= 0x80;
the_cpu->TriggerVICIRQ();
}
}
// Check sprite-background collisions
if (clx_bgr)
clx_bgr |= gfx_coll;
else {
clx_bgr |= gfx_coll;
irq_flag |= 0x02;
if (irq_mask & 0x02) {
irq_flag |= 0x80;
the_cpu->TriggerVICIRQ();
}
}
}
}
#ifdef __POWERPC__
static asm void fastcopy(register uchar *dst, register uchar *src);
static asm void fastcopy(register uchar *dst, register uchar *src)
{
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
lfd fp0,0(src)
lfd fp1,8(src)
lfd fp2,16(src)
lfd fp3,24(src)
lfd fp4,32(src)
lfd fp5,40(src)
lfd fp6,48(src)
lfd fp7,56(src)
addi src,src,64
stfd fp0,0(dst)
stfd fp1,8(dst)
stfd fp2,16(dst)
stfd fp3,24(dst)
stfd fp4,32(dst)
stfd fp5,40(dst)
stfd fp6,48(dst)
stfd fp7,56(dst)
addi dst,dst,64
blr
}
#endif
/*
* Emulate one clock cycle, returns true if new raster line has started
*/
// Set BA low
#define SetBALow \
if (!the_cpu->BALow) { \
first_ba_cycle = the_c64->CycleCounter; \
the_cpu->BALow = true; \
}
// Turn on display if Bad Line
#define DisplayIfBadLine \
if (is_bad_line) \
display_state = true;
// Turn on display and matrix access if Bad Line
#define FetchIfBadLine \
if (is_bad_line) { \
display_state = true; \
SetBALow; \
}
// Turn on display and matrix access and reset RC if Bad Line
#define RCIfBadLine \
if (is_bad_line) { \
display_state = true; \
rc = 0; \
SetBALow; \
}
// Idle access
#define IdleAccess \
read_byte(0x3fff)
// Refresh access
#define RefreshAccess \
read_byte(0x3f00 | ref_cnt--)
// Turn on sprite DMA if necessary
#define CheckSpriteDMA \
mask = 1; \
for (i=0; i<8; i++, mask<<=1) \
if ((me & mask) && (raster_y & 0xff) == my[i]) { \
spr_dma_on |= mask; \
mc_base[i] = 0; \
if (mye & mask) \
spr_exp_y &= ~mask; \
}
// Fetch sprite data pointer
#define SprPtrAccess(num) \
spr_ptr[num] = read_byte(matrix_base | 0x03f8 | num) << 6;
// Fetch sprite data, increment data counter
#define SprDataAccess(num, bytenum) \
if (spr_dma_on & (1 << num)) { \
spr_data[num][bytenum] = read_byte((mc[num] & 0x3f) | spr_ptr[num]); \
mc[num]++; \
} else if (bytenum == 1) \
IdleAccess;
// Sample border color and increment chunky_ptr and fore_mask_ptr
#define SampleBorder \
if (draw_this_line) { \
if (border_on) \
border_color_sample[cycle-13] = ec_color; \
chunky_ptr += 8; \
fore_mask_ptr++; \
}
bool MOS6569::EmulateCycle(void)
{
uint8 mask;
int i;
switch (cycle) {
// Fetch sprite pointer 3, increment raster counter, trigger raster IRQ,
// test for Bad Line, reset BA if sprites 3 and 4 off, read data of sprite 3
case 1:
if (raster_y == TOTAL_RASTERS-1)
// Trigger VBlank in cycle 2
vblanking = true;
else {
// Increment raster counter
raster_y++;
// Trigger raster IRQ if IRQ line reached
if (raster_y == irq_raster)
raster_irq();
// In line $30, the DEN bit controls if Bad Lines can occur
if (raster_y == 0x30)
bad_lines_enabled = ctrl1 & 0x10;
// Bad Line condition?
is_bad_line = (raster_y >= FIRST_DMA_LINE && raster_y <= LAST_DMA_LINE && ((raster_y & 7) == y_scroll) && bad_lines_enabled);
// Don't draw all lines, hide some at the top and bottom
draw_this_line = (raster_y >= FIRST_DISP_LINE && raster_y <= LAST_DISP_LINE && !frame_skipped);
}
// First sample of border state
border_on_sample[0] = border_on;
SprPtrAccess(3);
SprDataAccess(3, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x18))
the_cpu->BALow = false;
break;
// Set BA for sprite 5, read data of sprite 3
case 2:
if (vblanking) {
// Vertical blank, reset counters
raster_y = vc_base = 0;
ref_cnt = 0xff;
lp_triggered = vblanking = false;
if (!(frame_skipped = --skip_counter))
skip_counter = ThePrefs.SkipFrames;
the_c64->VBlank(!frame_skipped);
// Get bitmap pointer for next frame. This must be done
// after calling the_c64->VBlank() because the preferences
// and screen configuration may have been changed there
chunky_line_start = the_display->BitmapBase();
xmod = the_display->BitmapXMod();
// Trigger raster IRQ if IRQ in line 0
if (irq_raster == 0)
raster_irq();
}
// Our output goes here
#ifdef __POWERPC__
chunky_ptr = (uint8 *)chunky_tmp;
#else
chunky_ptr = chunky_line_start;
#endif
// Clear foreground mask
memset(fore_mask_buf, 0, DISPLAY_X/8);
fore_mask_ptr = fore_mask_buf;
SprDataAccess(3,1);
SprDataAccess(3,2);
DisplayIfBadLine;
if (spr_dma_on & 0x20)
SetBALow;
break;
// Fetch sprite pointer 4, reset BA is sprite 4 and 5 off
case 3:
SprPtrAccess(4);
SprDataAccess(4, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x30))
the_cpu->BALow = false;
break;
// Set BA for sprite 6, read data of sprite 4
case 4:
SprDataAccess(4, 1);
SprDataAccess(4, 2);
DisplayIfBadLine;
if (spr_dma_on & 0x40)
SetBALow;
break;
// Fetch sprite pointer 5, reset BA if sprite 5 and 6 off
case 5:
SprPtrAccess(5);
SprDataAccess(5, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x60))
the_cpu->BALow = false;
break;
// Set BA for sprite 7, read data of sprite 5
case 6:
SprDataAccess(5, 1);
SprDataAccess(5, 2);
DisplayIfBadLine;
if (spr_dma_on & 0x80)
SetBALow;
break;
// Fetch sprite pointer 6, reset BA if sprite 6 and 7 off
case 7:
SprPtrAccess(6);
SprDataAccess(6, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0xc0))
the_cpu->BALow = false;
break;
// Read data of sprite 6
case 8:
SprDataAccess(6, 1);
SprDataAccess(6, 2);
DisplayIfBadLine;
break;
// Fetch sprite pointer 7, reset BA if sprite 7 off
case 9:
SprPtrAccess(7);
SprDataAccess(7, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x80))
the_cpu->BALow = false;
break;
// Read data of sprite 7
case 10:
SprDataAccess(7, 1);
SprDataAccess(7, 2);
DisplayIfBadLine;
break;
// Refresh, reset BA
case 11:
RefreshAccess;
DisplayIfBadLine;
the_cpu->BALow = false;
break;
// Refresh, turn on matrix access if Bad Line
case 12:
RefreshAccess;
FetchIfBadLine;
break;
// Refresh, turn on matrix access if Bad Line, reset raster_x, graphics display starts here
case 13:
draw_background();
SampleBorder;
RefreshAccess;
FetchIfBadLine;
raster_x = 0xfffc;
break;
// Refresh, VCBASE->VCCOUNT, turn on matrix access and reset RC if Bad Line
case 14:
draw_background();
SampleBorder;
RefreshAccess;
RCIfBadLine;
vc = vc_base;
break;
// Refresh and matrix access, increment mc_base by 2 if y expansion flipflop is set
case 15:
draw_background();
SampleBorder;
RefreshAccess;
FetchIfBadLine;
for (i=0; i<8; i++)
if (spr_exp_y & (1 << i))
mc_base[i] += 2;
ml_index = 0;
matrix_access();
break;
// Graphics and matrix access, increment mc_base by 1 if y expansion flipflop is set
// and check if sprite DMA can be turned off
case 16:
draw_background();
SampleBorder;
graphics_access();
FetchIfBadLine;
mask = 1;
for (i=0; i<8; i++, mask<<=1) {
if (spr_exp_y & mask)
mc_base[i]++;
if ((mc_base[i] & 0x3f) == 0x3f)
spr_dma_on &= ~mask;
}
matrix_access();
break;
// Graphics and matrix access, turn off border in 40 column mode, display window starts here
case 17:
if (ctrl2 & 8) {
if (raster_y == dy_stop)
ud_border_on = true;
else {
if (ctrl1 & 0x10) {
if (raster_y == dy_start)
border_on = ud_border_on = false;
else
if (!ud_border_on)
border_on = false;
} else
if (!ud_border_on)
border_on = false;
}
}
// Second sample of border state
border_on_sample[1] = border_on;
draw_background();
draw_graphics();
SampleBorder;
graphics_access();
FetchIfBadLine;
matrix_access();
break;
// Turn off border in 38 column mode
case 18:
if (!(ctrl2 & 8)) {
if (raster_y == dy_stop)
ud_border_on = true;
else {
if (ctrl1 & 0x10) {
if (raster_y == dy_start)
border_on = ud_border_on = false;
else
if (!ud_border_on)
border_on = false;
} else
if (!ud_border_on)
border_on = false;
}
}
// Third sample of border state
border_on_sample[2] = border_on;
// Falls through
// Graphics and matrix access
case 19: case 20: case 21: case 22: case 23: case 24:
case 25: case 26: case 27: case 28: case 29: case 30:
case 31: case 32: case 33: case 34: case 35: case 36:
case 37: case 38: case 39: case 40: case 41: case 42:
case 43: case 44: case 45: case 46: case 47: case 48:
case 49: case 50: case 51: case 52: case 53: case 54: // Gnagna...
draw_graphics();
SampleBorder;
graphics_access();
FetchIfBadLine;
matrix_access();
last_char_data = char_data;
break;
// Last graphics access, turn off matrix access, turn on sprite DMA if Y coordinate is
// right and sprite is enabled, handle sprite y expansion, set BA for sprite 0
case 55:
draw_graphics();
SampleBorder;
graphics_access();
DisplayIfBadLine;
// Invert y expansion flipflop if bit in MYE is set
mask = 1;
for (i=0; i<8; i++, mask<<=1)
if (mye & mask)
spr_exp_y ^= mask;
CheckSpriteDMA;
if (spr_dma_on & 0x01) { // Don't remove these braces!
SetBALow;
} else
the_cpu->BALow = false;
break;
// Turn on border in 38 column mode, turn on sprite DMA if Y coordinate is right and
// sprite is enabled, set BA for sprite 0, display window ends here
case 56:
if (!(ctrl2 & 8))
border_on = true;
// Fourth sample of border state
border_on_sample[3] = border_on;
draw_graphics();
SampleBorder;
IdleAccess;
DisplayIfBadLine;
CheckSpriteDMA;
if (spr_dma_on & 0x01)
SetBALow;
break;
// Turn on border in 40 column mode, set BA for sprite 1, paint sprites
case 57:
if (ctrl2 & 8)
border_on = true;
// Fifth sample of border state
border_on_sample[4] = border_on;
// Sample spr_disp_on and spr_data for sprite drawing
if ((spr_draw = spr_disp_on) != 0)
memcpy(spr_draw_data, spr_data, 8*4);
// Turn off sprite display if DMA is off
mask = 1;
for (i=0; i<8; i++, mask<<=1)
if ((spr_disp_on & mask) && !(spr_dma_on & mask))
spr_disp_on &= ~mask;
draw_background();
SampleBorder;
IdleAccess;
DisplayIfBadLine;
if (spr_dma_on & 0x02)
SetBALow;
break;
// Fetch sprite pointer 0, mc_base->mc, turn on sprite display if necessary,
// turn off display if RC=7, read data of sprite 0
case 58:
draw_background();
SampleBorder;
mask = 1;
for (i=0; i<8; i++, mask<<=1) {
mc[i] = mc_base[i];
if ((spr_dma_on & mask) && (raster_y & 0xff) == my[i])
spr_disp_on |= mask;
}
SprPtrAccess(0);
SprDataAccess(0, 0);
if (rc == 7) {
vc_base = vc;
display_state = false;
}
if (is_bad_line || display_state) {
display_state = true;
rc = (rc + 1) & 7;
}
break;
// Set BA for sprite 2, read data of sprite 0
case 59:
draw_background();
SampleBorder;
SprDataAccess(0, 1);
SprDataAccess(0, 2);
DisplayIfBadLine;
if (spr_dma_on & 0x04)
SetBALow;
break;
// Fetch sprite pointer 1, reset BA if sprite 1 and 2 off, graphics display ends here
case 60:
draw_background();
SampleBorder;
if (draw_this_line) {
// Draw sprites
if (spr_draw && ThePrefs.SpritesOn)
draw_sprites();
// Draw border
#ifdef __POWERPC__
if (border_on_sample[0])
for (i=0; i<4; i++)
memset8((uint8 *)chunky_tmp+i*8, border_color_sample[i]);
if (border_on_sample[1])
memset8((uint8 *)chunky_tmp+4*8, border_color_sample[4]);
if (border_on_sample[2])
for (i=5; i<43; i++)
memset8((uint8 *)chunky_tmp+i*8, border_color_sample[i]);
if (border_on_sample[3])
memset8((uint8 *)chunky_tmp+43*8, border_color_sample[43]);
if (border_on_sample[4])
for (i=44; i<DISPLAY_X/8; i++)
memset8((uint8 *)chunky_tmp+i*8, border_color_sample[i]);
#else
if (border_on_sample[0])
for (i=0; i<4; i++)
memset8(chunky_line_start+i*8, border_color_sample[i]);
if (border_on_sample[1])
memset8(chunky_line_start+4*8, border_color_sample[4]);
if (border_on_sample[2])
for (i=5; i<43; i++)
memset8(chunky_line_start+i*8, border_color_sample[i]);
if (border_on_sample[3])
memset8(chunky_line_start+43*8, border_color_sample[43]);
if (border_on_sample[4])
for (i=44; i<DISPLAY_X/8; i++)
memset8(chunky_line_start+i*8, border_color_sample[i]);
#endif
#ifdef __POWERPC__
// Copy temporary buffer to bitmap
fastcopy(chunky_line_start, (uint8 *)chunky_tmp);
#endif
// Increment pointer in chunky buffer
chunky_line_start += xmod;
}
SprPtrAccess(1);
SprDataAccess(1, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x06))
the_cpu->BALow = false;
break;
// Set BA for sprite 3, read data of sprite 1
case 61:
SprDataAccess(1, 1);
SprDataAccess(1, 2);
DisplayIfBadLine;
if (spr_dma_on & 0x08)
SetBALow;
break;
// Read sprite pointer 2, reset BA if sprite 2 and 3 off, read data of sprite 2
case 62:
SprPtrAccess(2);
SprDataAccess(2, 0);
DisplayIfBadLine;
if (!(spr_dma_on & 0x0c))
the_cpu->BALow = false;
break;
// Set BA for sprite 4, read data of sprite 2
case 63:
SprDataAccess(2, 1);
SprDataAccess(2, 2);
DisplayIfBadLine;
if (raster_y == dy_stop)
ud_border_on = true;
else
if (ctrl1 & 0x10 && raster_y == dy_start)
ud_border_on = false;
if (spr_dma_on & 0x10)
SetBALow;
// Last cycle
raster_x += 8;
cycle = 1;
return true;
}
// Next cycle
raster_x += 8;
cycle++;
return false;
}
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