1 // license:BSD-3-Clause
2 // copyright-holders: R. Belmont
3 /****************************************************************************
4
5 micro20.cpp
6 GMX Micro 20 single-board computer
7
8 68020 + 68881 FPU
9
10 800a5e = end of initial 68020 torture test
11 ****************************************************************************/
12
13 #include "emu.h"
14 #include "cpu/m68000/m68000.h"
15 #include "machine/mc68681.h"
16 #include "machine/msm58321.h"
17 #include "machine/timer.h"
18 #include "machine/wd_fdc.h"
19 #include "machine/68230pit.h"
20 #include "bus/rs232/rs232.h"
21 #include "softlist.h"
22
23 #define MAINCPU_TAG "maincpu"
24 #define DUART_A_TAG "duarta"
25 #define DUART_B_TAG "duartb"
26 #define RTC_TAG "rtc"
27 #define FDC_TAG "fdc"
28 #define PIT_TAG "pit"
29
30 class micro20_state : public driver_device
31 {
32 public:
micro20_state(const machine_config & mconfig,device_type type,const char * tag)33 micro20_state(const machine_config &mconfig, device_type type, const char *tag) :
34 driver_device(mconfig, type, tag),
35 m_maincpu(*this, MAINCPU_TAG),
36 m_rom(*this, "bootrom"),
37 m_mainram(*this, "mainram"),
38 m_pit(*this, PIT_TAG),
39 m_rtc(*this, RTC_TAG)
40 {
41 }
42
43 void micro20(machine_config &config);
44
45 private:
46 required_device<m68020_device> m_maincpu;
47 required_memory_region m_rom;
48 required_shared_ptr<uint32_t> m_mainram;
49 required_device<pit68230_device> m_pit;
50 required_device<msm58321_device> m_rtc;
51
52 virtual void machine_start() override;
53 virtual void machine_reset() override;
54
55 DECLARE_WRITE_LINE_MEMBER(m68k_reset_callback);
56 u32 buserror_r();
57
58 TIMER_DEVICE_CALLBACK_MEMBER(micro20_timer);
59 DECLARE_WRITE_LINE_MEMBER(h4_w);
60 void portb_w(u8 data);
61 void portc_w(u8 data);
62
DECLARE_WRITE_LINE_MEMBER(timerirq_w)63 DECLARE_WRITE_LINE_MEMBER(timerirq_w)
64 {
65 m_maincpu->set_input_line(M68K_IRQ_4, state);
66 }
67
68 void micro20_map(address_map &map);
69
70 u8 m_tin;
71 u8 m_h4;
72 };
73
machine_start()74 void micro20_state::machine_start()
75 {
76 }
77
machine_reset()78 void micro20_state::machine_reset()
79 {
80 u32 *pROM = (uint32_t *)m_rom->base();
81 u32 *pRAM = (uint32_t *)m_mainram.target();
82
83 pRAM[0] = pROM[2];
84 pRAM[1] = pROM[3];
85 m_maincpu->reset();
86
87 m_maincpu->set_reset_callback(*this, FUNC(micro20_state::m68k_reset_callback));
88
89 m_tin = 0;
90 }
91
TIMER_DEVICE_CALLBACK_MEMBER(micro20_state::micro20_timer)92 TIMER_DEVICE_CALLBACK_MEMBER(micro20_state::micro20_timer)
93 {
94 m_pit->update_tin(m_tin ? ASSERT_LINE : CLEAR_LINE);
95 if (!m_h4 && m_tin)
96 m_maincpu->set_input_line(M68K_IRQ_6, HOLD_LINE);
97
98 m_tin ^= 1;
99 }
100
WRITE_LINE_MEMBER(micro20_state::h4_w)101 WRITE_LINE_MEMBER(micro20_state::h4_w)
102 {
103 printf("h4_w: %d\n", state);
104 m_h4 = state ^ 1;
105 }
106
WRITE_LINE_MEMBER(micro20_state::m68k_reset_callback)107 WRITE_LINE_MEMBER(micro20_state::m68k_reset_callback)
108 {
109 // startup test explicitly checks if the m68k RESET opcode resets the 68230
110 m_pit->reset();
111 }
112
portb_w(u8 data)113 void micro20_state::portb_w(u8 data)
114 {
115 m_rtc->d0_w((data & 1) ? ASSERT_LINE : CLEAR_LINE);
116 m_rtc->d1_w((data & 2) ? ASSERT_LINE : CLEAR_LINE);
117 m_rtc->d2_w((data & 4) ? ASSERT_LINE : CLEAR_LINE);
118 m_rtc->d3_w((data & 8) ? ASSERT_LINE : CLEAR_LINE);
119 }
120
portc_w(u8 data)121 void micro20_state::portc_w(u8 data)
122 {
123 // MSM58321 CS1 and CS2 are tied to /RST, inverted RESET.
124 // So they're always high when the system is not reset.
125 m_rtc->cs1_w(ASSERT_LINE);
126 m_rtc->cs2_w(ASSERT_LINE);
127 m_rtc->stop_w((data & 1) ? ASSERT_LINE : CLEAR_LINE);
128 m_rtc->write_w((data & 2) ? ASSERT_LINE : CLEAR_LINE);
129 m_rtc->read_w((data & 0x10) ? ASSERT_LINE : CLEAR_LINE);
130 m_rtc->address_write_w((data & 0x40) ? ASSERT_LINE : CLEAR_LINE);
131 m_rtc->test_w((data & 0x80) ? ASSERT_LINE : CLEAR_LINE);
132 }
133
buserror_r()134 u32 micro20_state::buserror_r()
135 {
136 m_maincpu->set_input_line(M68K_LINE_BUSERROR, ASSERT_LINE);
137 m_maincpu->set_input_line(M68K_LINE_BUSERROR, CLEAR_LINE);
138 return 0xffff;
139 }
140 /***************************************************************************
141 ADDRESS MAPS
142 ***************************************************************************/
143
micro20_map(address_map & map)144 void micro20_state::micro20_map(address_map &map)
145 {
146 map(0x00000000, 0x001fffff).ram().share("mainram");
147 map(0x00200000, 0x002fffff).r(FUNC(micro20_state::buserror_r));
148 map(0x00800000, 0x0083ffff).rom().region("bootrom", 0);
149 map(0xffff8000, 0xffff8000).rw(FDC_TAG, FUNC(wd1772_device::status_r), FUNC(wd1772_device::cmd_w));
150 map(0xffff8001, 0xffff8001).rw(FDC_TAG, FUNC(wd1772_device::track_r), FUNC(wd1772_device::track_w));
151 map(0xffff8002, 0xffff8002).rw(FDC_TAG, FUNC(wd1772_device::sector_r), FUNC(wd1772_device::sector_w));
152 map(0xffff8003, 0xffff8003).rw(FDC_TAG, FUNC(wd1772_device::data_r), FUNC(wd1772_device::data_w));
153 map(0xffff8080, 0xffff808f).rw(DUART_A_TAG, FUNC(mc68681_device::read), FUNC(mc68681_device::write));
154 map(0xffff80a0, 0xffff80af).rw(DUART_B_TAG, FUNC(mc68681_device::read), FUNC(mc68681_device::write));
155 map(0xffff80c0, 0xffff80df).rw(m_pit, FUNC(pit68230_device::read), FUNC(pit68230_device::write));
156 }
157
158 static DEVICE_INPUT_DEFAULTS_START( terminal )
159 DEVICE_INPUT_DEFAULTS( "RS232_TXBAUD", 0xff, RS232_BAUD_19200 )
160 DEVICE_INPUT_DEFAULTS( "RS232_RXBAUD", 0xff, RS232_BAUD_19200 )
161 DEVICE_INPUT_DEFAULTS( "RS232_STARTBITS", 0xff, RS232_STARTBITS_1 )
162 DEVICE_INPUT_DEFAULTS( "RS232_DATABITS", 0xff, RS232_DATABITS_7 )
163 DEVICE_INPUT_DEFAULTS( "RS232_PARITY", 0xff, RS232_PARITY_NONE )
164 DEVICE_INPUT_DEFAULTS( "RS232_STOPBITS", 0xff, RS232_STOPBITS_1 )
165 DEVICE_INPUT_DEFAULTS_END
166
micro20(machine_config & config)167 void micro20_state::micro20(machine_config &config)
168 {
169 /* basic machine hardware */
170 M68020(config, m_maincpu, 16.67_MHz_XTAL);
171 m_maincpu->set_addrmap(AS_PROGRAM, µ20_state::micro20_map);
172
173 mc68681_device &duart_a(MC68681(config, DUART_A_TAG, 3.6864_MHz_XTAL));
174 duart_a.a_tx_cb().set("rs232", FUNC(rs232_port_device::write_txd));
175
176 rs232_port_device &rs232(RS232_PORT(config, "rs232", default_rs232_devices, "terminal"));
177 rs232.rxd_handler().set(DUART_A_TAG, FUNC(mc68681_device::rx_a_w));
178 rs232.set_option_device_input_defaults("terminal", DEVICE_INPUT_DEFAULTS_NAME(terminal));
179
180 MC68681(config, DUART_B_TAG, 3.6864_MHz_XTAL);
181
182 WD1772(config, FDC_TAG, 16.67_MHz_XTAL / 2);
183
184 PIT68230(config, m_pit, 16.67_MHz_XTAL / 2);
185 m_pit->timer_irq_callback().set(FUNC(micro20_state::timerirq_w));
186 m_pit->h4_out_callback().set(FUNC(micro20_state::h4_w));
187 m_pit->pb_out_callback().set(FUNC(micro20_state::portb_w));
188 m_pit->pc_out_callback().set(FUNC(micro20_state::portc_w));
189
190 MSM58321(config, m_rtc, 32768_Hz_XTAL);
191 m_rtc->set_default_24h(false);
192 m_rtc->d0_handler().set(m_pit, FUNC(pit68230_device::pb0_w));
193 m_rtc->d1_handler().set(m_pit, FUNC(pit68230_device::pb1_w));
194 m_rtc->d2_handler().set(m_pit, FUNC(pit68230_device::pb2_w));
195 m_rtc->d3_handler().set(m_pit, FUNC(pit68230_device::pb3_w));
196 m_rtc->busy_handler().set(m_pit, FUNC(pit68230_device::pb7_w));
197
198 TIMER(config, "timer").configure_periodic(FUNC(micro20_state::micro20_timer), attotime::from_hz(200));
199 }
200
201 static INPUT_PORTS_START( micro20 )
202 INPUT_PORTS_END
203
204 /***************************************************************************
205
206 Machine driver(s)
207
208 ***************************************************************************/
209
210
211 ROM_START( micro20 )
212 ROM_REGION32_BE(0x40000, "bootrom", 0)
213 ROM_LOAD32_BYTE( "d00-07_u6_6791.bin", 0x000003, 0x010000, CRC(63d66ea1) SHA1(c5dfbc4d81920e1d2e981c52c1af3d486d382a35) )
214 ROM_LOAD32_BYTE( "d08-15_u8_0dc6.bin", 0x000002, 0x010000, CRC(d62ef21f) SHA1(2779d430b1a0b835807627e707d46547b29ef579) )
215 ROM_LOAD32_BYTE( "d16-23_u10_e5b0.bin", 0x000001, 0x010000, CRC(cd7acf86) SHA1(db994ed714a1079fbb66616355e8f18d2d1a2005) )
216 ROM_LOAD32_BYTE( "d24-31_u13_d115.bin", 0x000000, 0x010000, CRC(3646d943) SHA1(97ee54063e2fe49fef2ff68d0f2e39345a75eac5) )
217 ROM_END
218
219 COMP( 1984, micro20, 0, 0, micro20, micro20, micro20_state, empty_init, "GMX", "Micro 20", MACHINE_NOT_WORKING | MACHINE_NO_SOUND )
220