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#include "emu.h"
#include "cpu/m6809/m6809.h"
#include "machine/6522via.h"
#include "includes/beezer.h"
TIMER_DEVICE_CALLBACK_MEMBER(beezer_state::beezer_interrupt)
{
int scanline = param;
via6522_device *via_0 = machine().device<via6522_device>("via6522_0");
via_0->write_ca2((scanline & 0x20) ? 1 : 0);
#if 0
if (scanline == 240) // actually unused by the game! (points to a tight loop)
m_maincpu->set_input_line(M6809_FIRQ_LINE, ASSERT_LINE);
else
m_maincpu->set_input_line(M6809_FIRQ_LINE, CLEAR_LINE);
#endif
}
UINT32 beezer_state::screen_update_beezer(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
UINT8 *videoram = m_videoram;
int x,y;
for (y = cliprect.min_y; y <= cliprect.max_y; y++)
for (x = cliprect.min_x; x <= cliprect.max_x; x+=2)
{
bitmap.pix16(y, x+1) = videoram[0x80*x+y] & 0x0f;
bitmap.pix16(y, x+0) = videoram[0x80*x+y] >> 4;
}
return 0;
}
WRITE8_MEMBER(beezer_state::beezer_map_w)
{
/*
bit 7 -- 330 ohm resistor -- BLUE
-- 560 ohm resistor -- BLUE
-- 330 ohm resistor -- GREEN
-- 560 ohm resistor -- GREEN
-- 1.2 kohm resistor -- GREEN
-- 330 ohm resistor -- RED
-- 560 ohm resistor -- RED
bit 0 -- 1.2 kohm resistor -- RED
*/
int r, g, b, bit0, bit1, bit2;
/* red component */
bit0 = (data >> 0) & 0x01;
bit1 = (data >> 1) & 0x01;
bit2 = (data >> 2) & 0x01;
r = 0x26 * bit0 + 0x50 * bit1 + 0x89 * bit2;
/* green component */
bit0 = (data >> 3) & 0x01;
bit1 = (data >> 4) & 0x01;
bit2 = (data >> 5) & 0x01;
g = 0x26 * bit0 + 0x50 * bit1 + 0x89 * bit2;
/* blue component */
bit0 = (data >> 6) & 0x01;
bit1 = (data >> 7) & 0x01;
b = 0x5f * bit0 + 0xa0 * bit1;
palette_set_color(machine(), offset, MAKE_RGB(r, g, b));
}
READ8_MEMBER(beezer_state::beezer_line_r)
{
return m_screen->vpos();
// Note: was (m_scanline & 0xfe) << 1; with scanline % 128
}
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