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
|
// license:BSD-3-Clause
// copyright-holders:Aaron Giles
#ifndef MAME_SOUND_YM2154_H
#define MAME_SOUND_YM2154_H
#pragma once
//**************************************************************************
// TYPE DEFINITIONS
//**************************************************************************
DECLARE_DEVICE_TYPE(YM2154, ym2154_device)
// ======================> ym2154_device
class ym2154_device : public device_t, public device_sound_interface, public device_memory_interface
{
static constexpr uint8_t ADDR_SHIFT = 6;
public:
// internal constructor
ym2154_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock);
// configuration helpers
auto irq_handler() { return m_update_irq.bind(); }
auto io_read_handler() { return m_io_read.bind(); }
auto io_write_handler() { return m_io_write.bind(); }
// register reads
u8 read(offs_t offset);
// register writes
void write(offs_t offset, u8 data);
protected:
// device-level overrides
virtual void device_start() override;
virtual void device_reset() override;
virtual void device_clock_changed() override;
// sound overrides
virtual void sound_stream_update(sound_stream &stream, std::vector<read_stream_view> const &inputs, std::vector<write_stream_view> &outputs) override;
// memory space configuration
virtual space_config_vector memory_space_config() const override;
TIMER_CALLBACK_MEMBER(delayed_irq);
private:
struct channel
{
channel() :
m_pos(0xfffffff), m_start(0), m_end(0), m_panpot(0), m_output_level(0), m_rate(0) { }
void reset()
{
m_pos = 0;
m_start = m_end = 0;
m_panpot = 0;
m_output_level = 0;
m_rate = 0;
}
void start()
{
m_pos = m_start << ADDR_SHIFT;
}
uint32_t m_pos;
uint16_t m_start;
uint16_t m_end;
uint8_t m_panpot;
uint8_t m_output_level;
uint8_t m_rate;
};
// internal helpers
u32 sample_rate() const { return device_t::clock() / 18 / 6; }
void update_irq_state(u8 state) { if (m_irq_state != state) { m_irq_state = state; m_update_irq(state); } }
// internal state
sound_stream *m_stream; // sound stream
emu_timer *m_timer; // two timers
uint16_t m_timer_count; // current timer count
uint8_t m_timer_enable; // timer enable
uint8_t m_irq_state; // current IRQ state
uint8_t m_irq_count; // current IRQ count
uint8_t m_total_level; // master volume
channel m_channel[12]; // output channels
devcb_write_line m_update_irq; // IRQ update callback
devcb_read8 m_io_read; // input port handler
devcb_write8 m_io_write; // output port handler
address_space_config const m_group0_config; // address space 0 config
address_space_config const m_group1_config; // address space 1 config
optional_memory_region m_group0_region; // group 0 memory region
optional_memory_region m_group1_region; // group 1 memory region
};
#endif // MAME_SOUND_YM2154_H
|