1 // license:BSD-3-Clause
2 // copyright-holders:Patrick Mackinlay
3
4 /*
5 * While not physically compatible, the RT PC keyboard protocol is logically
6 * and electrically identical to the PC/AT. This implementation is copied from
7 * pc_kbdc and implements the same bi-directional clock and data lines.
8 */
9
10 #include "emu.h"
11 #include "kbd_con.h"
12
13 #define LOG_GENERAL (1U << 0)
14
15 #define VERBOSE (LOG_GENERAL)
16 #include "logmacro.h"
17
18 DEFINE_DEVICE_TYPE(RTPC_KBD_CON, rtpc_kbd_con_device, "rtpc_kbd_con", "RT PC keyboard connector")
19
rtpc_kbd_con_device(machine_config const & mconfig,char const * tag,device_t * owner,u32 clock)20 rtpc_kbd_con_device::rtpc_kbd_con_device(machine_config const &mconfig, char const *tag, device_t *owner, u32 clock)
21 : device_t(mconfig, RTPC_KBD_CON, tag, owner, clock)
22 , device_single_card_slot_interface<device_rtpc_kbd_interface>(mconfig, *this)
23 , m_out_clock_cb(*this)
24 , m_out_data_cb(*this)
25 , m_clock_state(-1)
26 , m_data_state(-1)
27 , m_mb_clock_state(0)
28 , m_mb_data_state(0)
29 , m_kb_clock_state(1)
30 , m_kb_data_state(1)
31 , m_keyboard(nullptr)
32 {
33 }
34
device_config_complete()35 void rtpc_kbd_con_device::device_config_complete()
36 {
37 m_keyboard = get_card_device();
38 }
39
device_resolve_objects()40 void rtpc_kbd_con_device::device_resolve_objects()
41 {
42 m_out_clock_cb.resolve_safe();
43 m_out_data_cb.resolve_safe();
44 }
45
device_start()46 void rtpc_kbd_con_device::device_start()
47 {
48 save_item(NAME(m_clock_state));
49 save_item(NAME(m_data_state));
50
51 save_item(NAME(m_mb_clock_state));
52 save_item(NAME(m_mb_data_state));
53 save_item(NAME(m_kb_clock_state));
54 save_item(NAME(m_kb_data_state));
55
56 m_clock_state = -1;
57 m_data_state = -1;
58
59 m_mb_clock_state = 1;
60 m_mb_data_state = 1;
61 m_kb_clock_state = 1;
62 m_kb_data_state = 1;
63 }
64
update_clock_state(bool fromkb)65 void rtpc_kbd_con_device::update_clock_state(bool fromkb)
66 {
67 int new_clock_state = m_mb_clock_state & m_kb_clock_state;
68
69 if (new_clock_state != m_clock_state)
70 {
71 m_clock_state = new_clock_state;
72 LOG("%s clock: %d\n", fromkb? "<-" : "->", m_clock_state);
73
74 // send state to host
75 m_out_clock_cb(m_clock_state);
76
77 // send state to keyboard
78 if (m_keyboard)
79 m_keyboard->clock_w(m_clock_state);
80 }
81 }
82
update_data_state(bool fromkb)83 void rtpc_kbd_con_device::update_data_state(bool fromkb)
84 {
85 int new_data_state = m_mb_data_state & m_kb_data_state;
86
87 if (new_data_state != m_data_state)
88 {
89 m_data_state = new_data_state;
90 LOG("%s data: %d\n", fromkb? "<-" : "->", m_data_state);
91
92 // send state to host
93 m_out_data_cb(m_data_state);
94
95 // send state to keyboard
96 if (m_keyboard)
97 m_keyboard->data_w(m_data_state);
98 }
99 }
100
clock_write_from_mb(int state)101 void rtpc_kbd_con_device::clock_write_from_mb(int state)
102 {
103 m_mb_clock_state = state;
104 update_clock_state(false);
105 }
106
data_write_from_mb(int state)107 void rtpc_kbd_con_device::data_write_from_mb(int state)
108 {
109 m_mb_data_state = state;
110 update_data_state(false);
111 }
112
clock_write_from_kb(int state)113 void rtpc_kbd_con_device::clock_write_from_kb(int state)
114 {
115 m_kb_clock_state = state;
116 update_clock_state(true);
117 }
118
data_write_from_kb(int state)119 void rtpc_kbd_con_device::data_write_from_kb(int state)
120 {
121 m_kb_data_state = state;
122 update_data_state(true);
123 }
124
device_rtpc_kbd_interface(machine_config const & mconfig,device_t & device)125 device_rtpc_kbd_interface::device_rtpc_kbd_interface(machine_config const &mconfig, device_t &device)
126 : device_interface(device, "rtpc_kbd_if")
127 , m_port(dynamic_cast<rtpc_kbd_con_device *>(device.owner()))
128 {
129 }
130