/********************************************************************** mm58167.c - National Semiconductor MM58167 real-time clock emulation TODO: alarms and IRQs not used by the Apple /// and aren't implemented. **********************************************************************/ #include "mm58167.h" //************************************************************************** // LIVE DEVICE //************************************************************************** // device type definition const device_type MM58167 = &device_creator; // registers (0-7 are the live data, 8-f are the setting for the compare IRQ) typedef enum { R_CNT_MILLISECONDS = 0, // 0 = milliseconds R_CNT_HUNDTENTHS, // 1 = hundreds and tenths of seconds R_CNT_SECONDS, // 2 = seconds R_CNT_MINUTES, // 3 = minutes R_CNT_HOURS, // 4 = hours R_CNT_DAYOFWEEK, // 5 = day of the week R_CNT_DAYOFMONTH, // 6 = day of the month R_CNT_MONTH, // 7 = month R_RAM_MILLISECONDS, // 8 = milliseconds R_RAM_HUNDTENTHS, // 9 = hundreds and tenths of seconds R_RAM_SECONDS, // a = seconds R_RAM_MINUTES, // b = minutes R_RAM_HOURS, // c = hours R_RAM_DAYOFWEEK, // d = day of the week R_RAM_DAYOFMONTH, // e = day of the month R_RAM_MONTH, // f = month R_CTL_IRQSTATUS, // 10 = IRQ status (b7 = compare, b6 = 10th sec, b5 = sec, b4 = min, b3 = hour, b2 = day, b1 = week, b0 = month) R_CTL_IRQCONTROL, // 11 = IRQ control (same bit layout as status, but write here to enable/disable/clear) R_CTL_RESETCOUNTERS, // 12 = reset counters R_CTL_RESETRAM, // 13 = reset RAM R_CTL_STATUS, // 14 = status bit R_CTL_GOCMD, // 15 = GO Command R_CTL_STANDBYIRQ, // 16 = standby IRQ R_CTL_TESTMODE // 17 = test mode } mm58167_regs_t; //------------------------------------------------- // mm58167_device - constructor //------------------------------------------------- mm58167_device::mm58167_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : device_t(mconfig, MM58167, "National Semiconductor MM58167", tag, owner, clock, "mm58167", __FILE__), device_rtc_interface(mconfig, *this), m_irq_w(*this) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void mm58167_device::device_start() { // allocate timers m_clock_timer = timer_alloc(); m_clock_timer->adjust(attotime::from_hz(clock() / 32.768f), 0, attotime::from_hz(clock() / 32.768f)); m_irq_w.resolve_safe(); // state saving save_item(NAME(m_regs)); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void mm58167_device::device_reset() { set_current_time(machine()); m_regs[R_CTL_STATUS] = 0; // not busy m_milliseconds = 0; } INLINE UINT8 make_bcd(UINT8 data) { return ((data / 10) << 4) | (data % 10); } //------------------------------------------------- // device_timer - handler timer events //------------------------------------------------- void mm58167_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) { m_milliseconds++; if (m_milliseconds >= 999) { advance_seconds(); m_milliseconds = 0; } m_regs[R_CNT_MILLISECONDS] = make_bcd(m_milliseconds % 10); m_regs[R_CNT_HUNDTENTHS] = make_bcd(m_milliseconds / 10); } //------------------------------------------------- // rtc_clock_updated - //------------------------------------------------- void mm58167_device::rtc_clock_updated(int year, int month, int day, int day_of_week, int hour, int minute, int second) { m_regs[R_CNT_SECONDS] = make_bcd(second); // seconds (BCD) m_regs[R_CNT_MINUTES] = make_bcd(minute); // minutes (BCD) m_regs[R_CNT_HOURS] = make_bcd(hour); // hour (BCD) m_regs[R_CNT_DAYOFWEEK] = make_bcd(day_of_week); // day of the week (BCD) m_regs[R_CNT_DAYOFMONTH] = make_bcd(day); // day of the month (BCD) m_regs[R_CNT_MONTH] = make_bcd(month); // month (BCD) } READ8_MEMBER(mm58167_device::read) { // printf("read reg %x = %02x\n", offset, m_regs[offset]); return m_regs[offset]; } WRITE8_MEMBER(mm58167_device::write) { // printf("%02x to reg %x\n", data, offset); if ((offset >= R_RAM_MILLISECONDS) && (offset != R_CTL_IRQSTATUS)) { m_regs[offset] = data; } switch (offset) { // any write to this starts at the current time and zero milliseconds case R_CTL_GOCMD: m_milliseconds = 0; break; case R_CTL_RESETRAM: if (data == 0xff) { for (int i = R_RAM_MILLISECONDS; i < R_CTL_IRQSTATUS; i++) { m_regs[i] = 0; } } break; case R_CTL_IRQCONTROL: if (data != 0) { logerror("MM58167: IRQs not implemented\n"); } break; } }