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r31534 Wednesday 6th August, 2014 at 22:35:34 UTC by hap
fix array out of bounds access

[src/emu/machine]

rtc4543.c rtc4543.h

trunk/src/emu/machine/rtc4543.c

r31533	r31534
52	52	save_item(NAME(m_clk));
53	53	save_item(NAME(m_wr));
54	54	save_item(NAME(m_data));
	55	save_item(NAME(m_shiftreg));
55	56	save_item(NAME(m_regs));
56	57	save_item(NAME(m_curreg));
57	58	}
r31533	r31534
69	70	m_wr = 0;
70	71	m_clk = 0;
71	72	m_data = 0;
	73	m_shiftreg = 0;
72	74	m_curreg = 0;
	75	m_curbit = 0;
73	76	}
74	77
75	78
r31533	r31534
96	99	{
97	100	static const int weekday[7] = { 7, 1, 2, 3, 4, 5, 6 };
98	101
99		m_regs[0] = make_bcd(second);               // seconds (BCD, 0-59) in bits 0-6, bit 7 = battery low
100		m_regs[1] = make_bcd(minute);               // minutes (BCD, 0-59)
101		m_regs[2] = make_bcd(hour);                 // hour (BCD, 0-23)
102		m_regs[3] = make_bcd(weekday[day_of_week-1]);   // low nibble = day of the week
103		m_regs[3] |= (make_bcd(day) & 0x0f)<<4;     // high nibble = low digit of day
104		m_regs[4] = (make_bcd(day) >> 4);           // low nibble = high digit of day
105		m_regs[4] |= (make_bcd(month & 0x0f)<<4);   // high nibble = low digit of month
106		m_regs[5] = make_bcd(month & 0x0f) >> 4;    // low nibble = high digit of month
107		m_regs[5] |= (make_bcd(year % 10) << 4);    // high nibble = low digit of year
108		m_regs[6] = make_bcd(year % 100) >> 4;  // low nibble = tens digit of year (BCD, 0-9)
	102	m_regs[0] = make_bcd(second);                   // seconds (BCD, 0-59) in bits 0-6, bit 7 = battery low
	103	m_regs[1] = make_bcd(minute);                   // minutes (BCD, 0-59)
	104	m_regs[2] = make_bcd(hour);                     // hour (BCD, 0-23)
	105	m_regs[3] = make_bcd(weekday[day_of_week - 1]); // low nibble = day of the week
	106	m_regs[3] |= (make_bcd(day) & 0x0f) << 4;       // high nibble = low digit of day
	107	m_regs[4] = (make_bcd(day) >> 4);               // low nibble = high digit of day
	108	m_regs[4] |= (make_bcd(month & 0x0f) << 4);     // high nibble = low digit of month
	109	m_regs[5] = make_bcd(month & 0x0f) >> 4;        // low nibble = high digit of month
	110	m_regs[5] |= (make_bcd(year % 10) << 4);        // high nibble = low digit of year
	111	m_regs[6] = make_bcd(year % 100) >> 4;          // low nibble = tens digit of year (BCD, 0-9)
109	112	}
110	113
111	114	//-------------------------------------------------
r31533	r31534
116	119	{
117	120	if (VERBOSE) printf("RTC4543 '%s' CE: %u\n", tag(), state);
118	121
119		if (!state && m_ce)         // complete transfer
	122	if (!state && m_ce) // complete transfer
120	123	{
121	124	}
122		else if (state && !m_ce)    // start new data transfer
	125	else if (state && !m_ce) // start new data transfer
123	126	{
124	127	m_curreg = 0;
125		m_bit = 8;      // force immediate reload of output data
	128	m_curbit = 0; // force immediate reload of output data
126	129	}
127	130
128	131	m_ce = state;
r31533	r31534
149	152
150	153	if (!m_ce) return;
151	154
152		if (!m_clk && state) // rising edge - read data becomes valid here
	155	// rising edge - read data becomes valid here
	156	if (!m_clk && state)
153	157	{
154	158	if (!m_wr)
155	159	{
156		if (m_bit > 7)  // reload data?
	160	// reload data?
	161	if ((m_curbit & 7) == 0)
157	162	{
158		m_bit = 0;
159		m_data = m_regs[m_curreg++];
	163	m_shiftreg = m_regs[m_curreg++];
	164
160	165	if (VERBOSE)
161		logerror("RTC4543 '%s' sending byte: %02x\n", tag(), m_data);
	166	logerror("RTC4543 '%s' sending byte: %02x\n", tag(), m_shiftreg);
162	167	}
163		else            // no reload, just continue with the current byte
	168
	169	// shift data bit
	170	// note: output data does not change when clk at final bit
	171	if (m_curbit != 55)
164	172	{
165		m_data >>= 1;
	173	m_data = m_shiftreg & 1;
	174	m_curbit++;
	175	m_shiftreg >>= 1;
	176	data_cb(m_data);
166	177	}
167
168		m_bit++;
169
170		data_cb(m_data & 0x01);
171	178	}
172	179	}
173	180
r31533	r31534
183	190	{
184	191	if (VERBOSE) logerror("RTC4543 '%s' I/O: %u\n", tag(), state);
185	192
186		m_data |= (state & 1);
	193	m_data = state & 1;
187	194	}
188	195
189	196
r31533	r31534
193	200
194	201	READ_LINE_MEMBER( rtc4543_device::data_r )
195	202	{
196		return (m_data & 0x80) ? 1 : 0;
	203	return m_data;
197	204	}

trunk/src/emu/machine/rtc4543.h

r31533	r31534
64	64	int m_clk;
65	65	int m_wr;
66	66	int m_data;
	67	int m_shiftreg;
67	68	int m_regs[7];
68	69	int m_curreg;
69		int m_bit;
	70	int m_curbit;
70	71
71	72	// timers
72	73	emu_timer *m_clock_timer;

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