1 // license:BSD-3-Clause
2 // copyright-holders:Miodrag Milanovic, Robbbert
3 /***************************************************************************
4
5 Chaos2
6
7 2010-04-08 Skeleton driver.
8 2012-05-19 Connected to a terminal, system is usable [Robbbert]
9
10 This is a homebrew system: http://koo.corpus.cam.ac.uk/chaos/
11
12 There are no schematics or manuals, so the results might not be
13 totally accurate.
14
15 With the DOS config switch turned off, the only accepted input
16 is a line starting with '&'. The actual commands are unknown.
17
18 With DOS enabled, a large number of commands become available.
19 These are:
20 access, ask, ascdis, bpclr, bpset, close, control, copy, devfive, dir,
21 end, exec, execute, fill, find, goto, if, input, let, list, load, lowercase,
22 memdis, memset, open, port, read, reboot, runhex, run, save, type, typesl,
23 verify.
24 An example is: memdis 0 8 (memory dump starting at 0, show 8 lines)
25 Don't try 'fill' - it fills all memory with zeroes, crashing the system.
26
27 ToDo:
28 - Connect up floppy disk (WD1771 fdc, 5.25", single density,
29 no other info available)
30
31 ****************************************************************************/
32
33 #include "emu.h"
34 #include "cpu/s2650/s2650.h"
35 #include "machine/terminal.h"
36
37
38 class chaos_state : public driver_device
39 {
40 public:
chaos_state(const machine_config & mconfig,device_type type,const char * tag)41 chaos_state(const machine_config &mconfig, device_type type, const char *tag)
42 : driver_device(mconfig, type, tag)
43 , m_terminal(*this, "terminal")
44 , m_p_ram(*this, "ram")
45 , m_maincpu(*this, "maincpu")
46 { }
47
48 void chaos(machine_config &config);
49
50 private:
51 u8 port1e_r();
52 void port1f_w(u8 data);
53 u8 port90_r();
54 u8 port91_r();
55 void kbd_put(u8 data);
56 void data_map(address_map &map);
57 void io_map(address_map &map);
58 void mem_map(address_map &map);
59 u8 m_term_data;
60 void machine_reset() override;
61 void machine_start() override;
62 required_device<generic_terminal_device> m_terminal;
63 required_shared_ptr<u8> m_p_ram;
64 required_device<cpu_device> m_maincpu;
65 };
66
67
mem_map(address_map & map)68 void chaos_state::mem_map(address_map &map)
69 {
70 map.unmap_value_high();
71 map(0x0000, 0x7fff).ram().share("ram");
72 }
73
io_map(address_map & map)74 void chaos_state::io_map(address_map &map)
75 {
76 map.unmap_value_high();
77 map(0x1e, 0x1e).r(FUNC(chaos_state::port1e_r));
78 map(0x1f, 0x1f).rw(FUNC(chaos_state::port90_r), FUNC(chaos_state::port1f_w));
79 map(0x90, 0x90).r(FUNC(chaos_state::port90_r));
80 map(0x91, 0x91).r(FUNC(chaos_state::port91_r));
81 map(0x92, 0x92).w(m_terminal, FUNC(generic_terminal_device::write));
82 }
83
data_map(address_map & map)84 void chaos_state::data_map(address_map &map)
85 {
86 map(S2650_DATA_PORT, S2650_DATA_PORT).noprw(); // stops error log filling up while using debug
87 }
88
89 /* Input ports */
90 static INPUT_PORTS_START( chaos )
91 PORT_START("CONFIG")
92 PORT_CONFNAME( 0x01, 0x00, "Enable DOS")
DEF_STR(No)93 PORT_CONFSETTING( 0x01, DEF_STR(No))
94 PORT_CONFSETTING( 0x00, DEF_STR(Yes))
95 INPUT_PORTS_END
96
97
98 // Port 1E - Bit 0 indicates key pressed, Bit 1 indicates ok to output
99
100 u8 chaos_state::port1e_r()
101 {
102 return (m_term_data) ? 1 : 0;
103 }
104
port1f_w(u8 data)105 void chaos_state::port1f_w(u8 data)
106 {
107 // make the output readable on our terminal
108 if (data == 0x09)
109 return;
110 else
111 if (!data)
112 data = 0x24;
113
114 m_terminal->write(data);
115
116 if (data == 0x0d)
117 m_terminal->write(0x0a);
118 }
119
port90_r()120 u8 chaos_state::port90_r()
121 {
122 u8 ret = m_term_data;
123 m_term_data = 0;
124 return ret;
125 }
126
127 // Status port
128 // Bit 0 = L use ports 1E & 1F; H use ports 90 & 92
129 // Bit 3 = key pressed
130 // Bit 7 = ok to output
131
port91_r()132 u8 chaos_state::port91_r()
133 {
134 u8 ret = 0x80 | ioport("CONFIG")->read();
135 ret |= (m_term_data) ? 8 : 0;
136 return ret;
137 }
138
kbd_put(u8 data)139 void chaos_state::kbd_put(u8 data)
140 {
141 m_term_data = data;
142 }
143
machine_start()144 void chaos_state::machine_start()
145 {
146 save_item(NAME(m_term_data));
147 }
148
machine_reset()149 void chaos_state::machine_reset()
150 {
151 // copy the roms into ram
152 u8* ROM = memregion("roms")->base();
153 memcpy(m_p_ram, ROM, 0x3000);
154 memcpy(m_p_ram+0x7000, ROM+0x3000, 0x1000);
155 }
156
chaos(machine_config & config)157 void chaos_state::chaos(machine_config &config)
158 {
159 /* basic machine hardware */
160 S2650(config, m_maincpu, XTAL(1'000'000));
161 m_maincpu->set_addrmap(AS_PROGRAM, &chaos_state::mem_map);
162 m_maincpu->set_addrmap(AS_IO, &chaos_state::io_map);
163 m_maincpu->set_addrmap(AS_DATA, &chaos_state::data_map);
164
165 /* video hardware */
166 GENERIC_TERMINAL(config, m_terminal, 0);
167 m_terminal->set_keyboard_callback(FUNC(chaos_state::kbd_put));
168 }
169
170 /* ROM definition */
171 ROM_START( chaos )
172 ROM_REGION( 0x4000, "roms", 0 )
173 ROM_LOAD( "chaos.001", 0x0000, 0x1000, CRC(3b433e72) SHA1(5b487337d71253d0e64e123f405da9eaf20e87ac))
174 ROM_LOAD( "chaos.002", 0x1000, 0x1000, CRC(8b0b487f) SHA1(0d167cf3004a81c87446f2f1464e3debfa7284fe))
175 ROM_LOAD( "chaos.003", 0x2000, 0x1000, CRC(5880db81) SHA1(29b8f1b03c83953f66464ad1fbbfe2e019637ce1))
176 ROM_LOAD( "chaos.004", 0x3000, 0x1000, CRC(5d6839d6) SHA1(237f52f0780ac2e29d57bf06d0f7a982eb523084))
177 ROM_END
178
179 /* Driver */
180
181 // YEAR NAME PARENT COMPAT MACHINE INPUT CLASS INIT COMPANY FULLNAME FLAGS
182 COMP( 1983, chaos, 0, 0, chaos, chaos, chaos_state, empty_init, "David Greaves", "Chaos 2", MACHINE_NO_SOUND_HW | MACHINE_SUPPORTS_SAVE )
183