1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
// license:BSD-3-Clause
// copyright-holders:Sergey Svishchev
/***************************************************************************
Monochrome register-addressable framebuffer used in DVK.
To do: overlay on IE15's screen.
***************************************************************************/
#include "emu.h"
#include "dvk_kgd.h"
#include "emupal.h"
//**************************************************************************
// DEVICE DEFINITIONS
//**************************************************************************
DEFINE_DEVICE_TYPE(DVK_KGD, dvk_kgd_device, "kgd", "DVK KGD framebuffer")
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
//-------------------------------------------------
// dvk_kgd_device - constructor
//-------------------------------------------------
dvk_kgd_device::dvk_kgd_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, DVK_KGD, tag, owner, clock)
, device_qbus_card_interface(mconfig, *this)
, m_screen(*this, "screen")
{
}
uint32_t dvk_kgd_device::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
// CR bit 15: display graphics
// CR bit 14: pass through video signal (usually from IE15)
if (!(m_cr & (2 << 14)))
{
bitmap.fill(0);
return 0;
}
for (u16 y = 0; y < 286; y++)
{
for (u16 x = 0; x < 50; x++)
{
u16 const code = m_videoram[y * 50 + x];
for (u8 b = 0; b < 8; b++)
{
bitmap.pix(y, x * 16 + b + b) = BIT(code, b);
bitmap.pix(y, x * 16 + b + b + 1) = BIT(code, b);
}
}
}
return 0;
}
void dvk_kgd_device::device_add_mconfig(machine_config &config)
{
SCREEN(config, m_screen, SCREEN_TYPE_RASTER);
m_screen->set_color(rgb_t::green());
m_screen->set_screen_update(FUNC(dvk_kgd_device::screen_update));
m_screen->set_raw(XTAL(30'800'000) / 2, 800, 0, 800, 286, 0, 286);
m_screen->set_palette("palette");
PALETTE(config, "palette", palette_device::MONOCHROME);
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void dvk_kgd_device::device_start()
{
m_bus->install_device(0176640, 0176647, read16sm_delegate(*this, FUNC(dvk_kgd_device::read)),
write16sm_delegate(*this, FUNC(dvk_kgd_device::write)));
// save state
save_item(NAME(m_cr));
save_item(NAME(m_dr));
save_item(NAME(m_ar));
save_item(NAME(m_ct));
m_videoram_base = std::make_unique<uint8_t[]>(16384);
m_videoram = m_videoram_base.get();
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void dvk_kgd_device::device_reset()
{
m_cr = m_dr = m_ar = m_ct = 0;
}
//-------------------------------------------------
// read - register read
//-------------------------------------------------
uint16_t dvk_kgd_device::read(offs_t offset)
{
uint16_t data = 0;
switch (offset & 3)
{
case 0:
data = m_cr;
break;
case 1:
data = m_videoram[m_ar];
break;
case 2:
data = m_ar;
break;
case 3:
data = m_ct;
break;
}
return data;
}
//-------------------------------------------------
// write - register write
//-------------------------------------------------
void dvk_kgd_device::write(offs_t offset, uint16_t data)
{
switch (offset & 3)
{
case 0:
m_cr = ((m_cr & ~KGDCR_WR) | (data & KGDCR_WR));
break;
case 1:
m_dr = ((m_dr & ~KGDDR_WR) | (data & KGDDR_WR));
m_videoram[m_ar] = m_dr;
break;
case 2:
m_ar = ((m_ar & ~KGDAR_WR) | (data & KGDAR_WR));
break;
case 3:
m_ct = ((m_ct & ~KGDCT_WR) | (data & KGDCT_WR));
break;
}
}
|