summaryrefslogtreecommitdiffstatshomepage
path: root/src/emu/machine/msm6242.c
blob: d11c00def7962a736bd6dec08f74d4af2a2c2723 (plain) (blame)
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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
/***************************************************************************

    MSM6242 / Epson RTC 62421 / 62423 Real Time Clock

    TODO:
    - HOLD mechanism
    - IRQs are grossly mapped
    - STOP / RESET mechanism
    - why skns.c games try to read uninitialized registers?

***************************************************************************/

#include "emu.h"
#include "machine/msm6242.h"
#include "machine/devhelpr.h"


enum
{
	MSM6242_REG_S1		= 0,
	MSM6242_REG_S10,
	MSM6242_REG_MI1,
	MSM6242_REG_MI10,
	MSM6242_REG_H1,
	MSM6242_REG_H10,
	MSM6242_REG_D1,
	MSM6242_REG_D10,
	MSM6242_REG_MO1,
	MSM6242_REG_MO10,
	MSM6242_REG_Y1,
	MSM6242_REG_Y10,
	MSM6242_REG_W,
	MSM6242_REG_CD,
	MSM6242_REG_CE,
	MSM6242_REG_CF
};

//**************************************************************************
//  GLOBAL VARIABLES
//**************************************************************************

// device type definition
const device_type msm6242 = &device_creator<msm6242_device>;


//**************************************************************************
//  LIVE DEVICE
//**************************************************************************

//-------------------------------------------------
//  xxx_device - constructor
//-------------------------------------------------

msm6242_device::msm6242_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: device_t(mconfig, msm6242, "msm6242", tag, owner, clock)
{

}

void msm6242_device::rtc_timer_callback()
{
	static const UINT8 dpm[12] = { 0x31, 0x28, 0x31, 0x30, 0x31, 0x30, 0x31, 0x31, 0x30, 0x31, 0x30, 0x31 };
	int dpm_count;

	m_tick++;

	if(m_irq_flag == 1 && m_irq_type == 0 && ((m_tick % 0x200) == 0)) // 1/64 of second
	{
		if ( !m_out_int_func.isnull() )
			m_out_int_func( ASSERT_LINE );
	}

	if(m_tick & 0x8000) // 32,768 KHz == 0x8000 ticks
	{
		m_tick = 0;
		m_rtc.sec++;

		if(m_irq_flag == 1 && m_irq_type == 1) // 1 second clock
			if ( !m_out_int_func.isnull() )
				m_out_int_func(ASSERT_LINE);

		if(m_rtc.sec >= 60)
		{
			m_rtc.min++; m_rtc.sec = 0;
			if(m_irq_flag == 1 && m_irq_type == 2) // 1 minute clock
				if ( !m_out_int_func.isnull() )
					m_out_int_func(ASSERT_LINE);
		}
		if(m_rtc.min >= 60)
		{
			m_rtc.hour++; m_rtc.min = 0;
			if(m_irq_flag == 1 && m_irq_type == 3) // 1 hour clock
				if ( !m_out_int_func.isnull() )
					m_out_int_func(ASSERT_LINE);
		}
		if(m_rtc.hour >= 24)			{ m_rtc.day++; m_rtc.wday++; m_rtc.hour = 0; }
		if(m_rtc.wday >= 6)				{ m_rtc.wday = 1; }

		/* TODO: crude leap year support */
		dpm_count = (m_rtc.month)-1;

		if(((m_rtc.year % 4) == 0) && m_rtc.month == 2)
		{
			if((m_rtc.day) >= dpm[dpm_count]+1+1)
				{ m_rtc.month++; m_rtc.day = 0x01; }
		}
		else if(m_rtc.day >= dpm[dpm_count]+1)		{ m_rtc.month++; m_rtc.day = 0x01; }
		if(m_rtc.month >= 0x13)						{ m_rtc.year++; m_rtc.month = 1; }
		if(m_rtc.year >= 100)						{ m_rtc.year = 0; } //1900-1999 possible timeframe
	}
}

TIMER_CALLBACK( msm6242_device::rtc_inc_callback )
{
	reinterpret_cast<msm6242_device *>(ptr)->rtc_timer_callback();
}

//-------------------------------------------------
//  device_validity_check - perform validity checks
//  on this device
//-------------------------------------------------

void msm6242_device::device_validity_check(validity_checker &valid) const
{
}

//-------------------------------------------------
//  device_start - device-specific startup
//-------------------------------------------------

void msm6242_device::device_start()
{
	m_out_int_func.resolve( m_out_int_cb, *this );

	/* let's call the timer callback every second */
	machine().scheduler().timer_pulse(attotime::from_hz(clock()), FUNC(rtc_inc_callback), 0, (void *)this);

	system_time systime;
	machine().base_datetime(systime);

	m_rtc.day = (systime.local_time.mday);
	m_rtc.month = (systime.local_time.month+1);
	m_rtc.wday = (systime.local_time.weekday);
	m_rtc.year = (systime.local_time.year % 100);
	m_rtc.hour = (systime.local_time.hour);
	m_rtc.min = (systime.local_time.minute);
	m_rtc.sec = (systime.local_time.second);
	m_tick = 0;
	m_irq_flag = 0;
	m_irq_type = 0;

	/* TODO: skns writes 0x4 to D then expects E == 6 and F == 4, perhaps those are actually saved in the RTC CMOS? */
	m_reg[0] = 0;
	m_reg[1] = 0x6;
	m_reg[2] = 0x4;
}


//-------------------------------------------------
//  device_reset - device-specific reset
//-------------------------------------------------

void msm6242_device::device_reset()
{
	if ( !m_out_int_func.isnull() )
		m_out_int_func( CLEAR_LINE );
}


//-------------------------------------------------
//  device_config_complete - perform any
//  operations now that the configuration is
//  complete
//-------------------------------------------------

void msm6242_device::device_config_complete()
{
	const msm6242_interface *intf = reinterpret_cast<const msm6242_interface *>(static_config());

	if ( intf != NULL )
	{
		*static_cast<msm6242_interface *>(this) = *intf;
	}
	else
	{
		memset(&m_out_int_cb, 0, sizeof(m_out_int_cb));
	}
}

//**************************************************************************
//  READ/WRITE HANDLERS
//**************************************************************************

READ8_MEMBER( msm6242_device::read )
{
	rtc_regs_t cur_time;

	//cur_time = (m_reg[0] & 1) ? m_hold : m_rtc;

	cur_time = m_rtc;

	switch(offset)
	{
		case MSM6242_REG_S1: return (cur_time.sec % 10) & 0xf;
		case MSM6242_REG_S10: return (cur_time.sec / 10) & 0xf;
		case MSM6242_REG_MI1: return (cur_time.min % 10) & 0xf;
		case MSM6242_REG_MI10: return (cur_time.min / 10) & 0xf;
		case MSM6242_REG_H1:
		case MSM6242_REG_H10:
		{
			int	hour = cur_time.hour;
			int pm = 0;

			/* check for 12/24 hour mode */
			if ((m_reg[2] & 0x04) == 0) /* 12 hour mode? */
			{
				if (hour >= 12)
					pm = 1;

				hour %= 12;

				if ( hour == 0 )
					hour = 12;
			}

			if ( offset == MSM6242_REG_H1 )
				return hour % 10;

			return (hour / 10) | (pm <<2);
		}

		case MSM6242_REG_D1: return (cur_time.day % 10) & 0xf;
		case MSM6242_REG_D10: return (cur_time.day / 10) & 0xf;
		case MSM6242_REG_MO1: return (cur_time .month % 10) & 0xf;
		case MSM6242_REG_MO10: return (cur_time.month / 10) & 0xf;
		case MSM6242_REG_Y1: return (cur_time.year % 10) & 0xf;
		case MSM6242_REG_Y10: return ((cur_time.year / 10) % 10) & 0xf;
		case MSM6242_REG_W: return cur_time.wday;
		case MSM6242_REG_CD: return m_reg[0];
		case MSM6242_REG_CE: return m_reg[1];
		case MSM6242_REG_CF: return m_reg[2];
	}

	logerror("%s: MSM6242 unmapped offset %02x read\n", machine().describe_context(), offset);
	return 0;
}

WRITE8_MEMBER( msm6242_device::write )
{
	switch(offset)
	{
		case MSM6242_REG_CD:
		{
			/*
            x--- 30s ADJ
            -x-- IRQ FLAG
            --x- BUSY
            ---x HOLD
            */

			m_reg[0] = data & 0x0f;

			#if 0
			if (data & 1)	/* was Hold set? */
			{
				m_hold.day = m_rtc.day;
				m_hold.month = m_rtc.month;
				m_hold.hour = m_rtc.hour;
				m_hold.day = m_rtc.day;
				m_hold.month = m_rtc.month;
				m_hold.year = m_rtc.year;
				m_hold.wday = m_rtc.wday;
			}
			#endif

			return;
		}

		case MSM6242_REG_CE:
		{
			/*
            xx-- t0,t1 (timing irq)
            --x- STD
            ---x MASK
            */

			m_reg[1] = data & 0x0f;
			if((data & 3) == 0) // MASK & STD = 0
			{
				m_irq_flag = 1;
				m_irq_type = (data & 0xc) >> 2;
				//m_std_timer->adjust(attotime::from_msec(timer_param[(data & 0xc) >> 2]), 0, attotime::from_msec(timer_param[(data & 0xc) >> 2]));
			}
			else
			{
				m_irq_flag = 0;
				if ( !m_out_int_func.isnull() )
					m_out_int_func( CLEAR_LINE );
			}

			return;
		}

		case MSM6242_REG_CF:
		{
			/*
            x--- TEST
            -x-- 24/12
            --x- STOP
            ---x RESET
            */

			/* the 12/24 mode bit can only be changed when RESET does a 1 -> 0 transition */
			if (((data & 0x01) == 0x00) && (m_reg[2] & 0x01))
				m_reg[2] = (m_reg[2] & ~0x04) | (data & 0x04);
			else
				m_reg[2] = (data & 0x0b) | (m_reg[2] & 4);

			return;
		}
	}

	logerror("%s: MSM6242 unmapped offset %02x written with %02x\n", machine().describe_context(), offset, data);
}