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
|
// license:BSD-3-Clause
// copyright-holders:Curt Coder
/**********************************************************************
Intel 8255(A) Programmable Peripheral Interface emulation
**********************************************************************
_____ _____
PA3 1 |* \_/ | 40 PA4
PA2 2 | | 39 PA5
PA1 3 | | 38 PA6
PA0 4 | | 37 PA7
_RD 5 | | 36 WR
_CS 6 | | 35 RESET
GND 7 | | 34 D0
A1 8 | | 33 D1
A0 9 | | 32 D2
PC7 10 | 8255 | 31 D3
PC6 11 | 8255A | 30 D4
PC5 12 | | 29 D5
PC4 13 | | 28 D6
PC0 14 | | 27 D7
PC1 15 | | 26 Vcc
PC2 16 | | 25 PB7
PC3 17 | | 24 PB6
PB0 18 | | 23 PB5
PB1 19 | | 22 PB4
PB2 20 |_____________| 21 PB3
**********************************************************************/
#ifndef MAME_MACHINE_I8255_H
#define MAME_MACHINE_I8255_H
#pragma once
//**************************************************************************
// TYPE DEFINITIONS
//**************************************************************************
// ======================> i8255_device
class i8255_device : public device_t
{
public:
// construction/destruction
i8255_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
auto in_pa_callback() { return m_in_pa_cb.bind(); }
auto in_pb_callback() { return m_in_pb_cb.bind(); }
auto in_pc_callback() { return m_in_pc_cb.bind(); }
auto out_pa_callback() { return m_out_pa_cb.bind(); }
auto out_pb_callback() { return m_out_pb_cb.bind(); }
auto out_pc_callback() { return m_out_pc_cb.bind(); }
// output state when pins are in tri-state, default 0xff
auto tri_pa_callback() { return m_tri_pa_cb.bind(); }
auto tri_pb_callback() { return m_tri_pb_cb.bind(); }
auto tri_pc_callback() { return m_tri_pc_cb.bind(); }
uint8_t read(offs_t offset);
void write(offs_t offset, uint8_t data );
uint8_t pa_r();
uint8_t acka_r();
uint8_t pb_r();
uint8_t ackb_r();
void pc2_w(int state);
void pc4_w(int state);
void pc6_w(int state);
protected:
i8255_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock, bool is_ams40489);
// device-level overrides
virtual void device_resolve_objects() override;
virtual void device_start() override;
virtual void device_reset() override;
const bool m_force_portb_in;
const bool m_force_portc_out;
const bool m_dont_clear_output_latches;
private:
inline void check_interrupt(int port);
inline void set_ibf(int port, int state);
inline void set_obf(int port, int state);
inline void set_inte(int port, int state);
inline void set_inte1(int state);
inline void set_inte2(int state);
inline void set_intr(int port, int state);
inline int group_mode(int group);
inline int port_mode(int port);
inline int port_c_lower_mode();
inline int port_c_upper_mode();
uint8_t read_mode0(int port);
uint8_t read_mode1(int port);
uint8_t read_mode2();
uint8_t read_pc();
void write_mode0(int port, uint8_t data);
void write_mode1(int port, uint8_t data);
void write_mode2(uint8_t data);
void output_pc();
void set_mode(uint8_t data);
void set_pc_bit(int bit, int state);
devcb_read8 m_in_pa_cb;
devcb_read8 m_in_pb_cb;
devcb_read8 m_in_pc_cb;
devcb_write8 m_out_pa_cb;
devcb_write8 m_out_pb_cb;
devcb_write8 m_out_pc_cb;
devcb_read8 m_tri_pa_cb;
devcb_read8 m_tri_pb_cb;
devcb_read8 m_tri_pc_cb;
uint8_t m_control; // mode control word
uint8_t m_output[3]; // output latch
uint8_t m_input[3]; // input latch
int m_ibf[2]; // input buffer full flag
int m_obf[2]; // output buffer full flag, negative logic
int m_inte[2]; // interrupt enable
int m_inte1; // interrupt enable
int m_inte2; // interrupt enable
int m_intr[2]; // interrupt
};
// AMS40489 ASIC (Amstrad Plus/GX4000 PPI implementation)
class ams40489_ppi_device : public i8255_device
{
public:
// construction/destruction
ams40489_ppi_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
};
// device type definition
DECLARE_DEVICE_TYPE(I8255, i8255_device)
static auto &I8255A = I8255;
DECLARE_DEVICE_TYPE(AMS40489_PPI, ams40489_ppi_device)
#endif // MAME_MACHINE_I8255_H
|