diff options
author | 2020-12-07 14:57:31 -0500 | |
---|---|---|
committer | 2020-12-07 15:00:14 -0500 | |
commit | cc954c2adeb3aaec4402e8f893b1d591ebbf6c57 (patch) | |
tree | 11c013827294c528fb37863939c880f6a742554c /src/devices/cpu/z80/tmpz84c015.cpp | |
parent | 1c1355655531bbe0995ae6b7136503e920115c9e (diff) |
tmpz84c015: Add WDT emulation
Diffstat (limited to 'src/devices/cpu/z80/tmpz84c015.cpp')
-rw-r--r-- | src/devices/cpu/z80/tmpz84c015.cpp | 82 |
1 files changed, 78 insertions, 4 deletions
diff --git a/src/devices/cpu/z80/tmpz84c015.cpp b/src/devices/cpu/z80/tmpz84c015.cpp index 08ceb2bc1f0..329aec51f9f 100644 --- a/src/devices/cpu/z80/tmpz84c015.cpp +++ b/src/devices/cpu/z80/tmpz84c015.cpp @@ -8,7 +8,7 @@ TODO: - SIO configuration, or should that be up to the driver? - CGC (clock generator/controller) - - WDT (watchdog timer) + - Halt modes ***************************************************************************/ @@ -17,22 +17,26 @@ DEFINE_DEVICE_TYPE(TMPZ84C015, tmpz84c015_device, "tmpz84c015", "Toshiba TMPZ84C015") -void tmpz84c015_device::tmpz84c015_internal_io_map(address_map &map) +void tmpz84c015_device::internal_io_map(address_map &map) { map(0x10, 0x13).mirror(0xff00).rw(m_ctc, FUNC(z80ctc_device::read), FUNC(z80ctc_device::write)); map(0x18, 0x1b).mirror(0xff00).rw(m_sio, FUNC(z80sio_device::ba_cd_r), FUNC(z80sio_device::ba_cd_w)); map(0x1c, 0x1f).mirror(0xff00).rw(m_pio, FUNC(z80pio_device::read_alt), FUNC(z80pio_device::write_alt)); + map(0xf0, 0xf0).mirror(0xff00).rw(FUNC(tmpz84c015_device::wdtmr_r), FUNC(tmpz84c015_device::wdtmr_w)); + map(0xf1, 0xf1).mirror(0xff00).w(FUNC(tmpz84c015_device::wdtcr_w)); map(0xf4, 0xf4).mirror(0xff00).w(FUNC(tmpz84c015_device::irq_priority_w)); } tmpz84c015_device::tmpz84c015_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : z80_device(mconfig, TMPZ84C015, tag, owner, clock), - m_io_space_config( "io", ENDIANNESS_LITTLE, 8, 16, 0, address_map_constructor(FUNC(tmpz84c015_device::tmpz84c015_internal_io_map), this)), + m_io_space_config( "io", ENDIANNESS_LITTLE, 8, 16, 0, address_map_constructor(FUNC(tmpz84c015_device::internal_io_map), this)), m_ctc(*this, "tmpz84c015_ctc"), m_sio(*this, "tmpz84c015_sio"), m_pio(*this, "tmpz84c015_pio"), m_irq_priority(-1), // ! + m_wdtmr(0xfb), + m_watchdog_timer(nullptr), m_out_txda_cb(*this), m_out_dtra_cb(*this), @@ -59,7 +63,9 @@ tmpz84c015_device::tmpz84c015_device(const machine_config &mconfig, const char * m_in_pb_cb(*this), m_out_pb_cb(*this), - m_out_brdy_cb(*this) + m_out_brdy_cb(*this), + + m_wdtout_cb(*this) { } @@ -107,8 +113,14 @@ void tmpz84c015_device::device_start() m_out_pb_cb.resolve_safe(); m_out_brdy_cb.resolve_safe(); + m_wdtout_cb.resolve(); + + // setup watchdog timer + m_watchdog_timer = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(tmpz84c015_device::watchdog_timeout), this)); + // register for save states save_item(NAME(m_irq_priority)); + save_item(NAME(m_wdtmr)); } @@ -119,6 +131,9 @@ void tmpz84c015_device::device_start() void tmpz84c015_device::device_reset() { irq_priority_w(0); + m_wdtmr = 0xfb; + watchdog_clear(); + z80_device::device_reset(); } @@ -176,6 +191,65 @@ void tmpz84c015_device::irq_priority_w(uint8_t data) } } + +uint8_t tmpz84c015_device::wdtmr_r() +{ + return m_wdtmr; +} + +void tmpz84c015_device::wdtmr_w(uint8_t data) +{ + if ((data & 0x07) != 0x03) + logerror("%s: Writing %d%d%d to WDTMR reserved bits\n", machine().describe_context(), BIT(data, 2), BIT(data, 1), BIT(data, 0)); + + // check for watchdog timer enable + uint8_t old_data = std::exchange(m_wdtmr, data); + if (!BIT(old_data, 7) && BIT(data, 7)) + watchdog_clear(); +} + +void tmpz84c015_device::wdtcr_w(uint8_t data) +{ + // write specific values only + switch (data) + { + case 0x4e: + watchdog_clear(); + break; + + case 0xb1: + // WDTER must be cleared first + if (!BIT(m_wdtmr, 7)) + { + logerror("%s: Watchdog timer disabled\n", machine().describe_context()); + m_watchdog_timer->adjust(attotime::never); + } + break; + + default: + logerror("%s: Writing %02X to WDTCR\n", machine().describe_context(), data); + break; + } +} + +void tmpz84c015_device::watchdog_clear() +{ + if (!m_wdtout_cb.isnull()) + m_wdtout_cb(CLEAR_LINE); + + if (BIT(m_wdtmr, 7)) + m_watchdog_timer->adjust(cycles_to_attotime(0x10000 << (BIT(m_wdtmr, 5, 2) * 2))); +} + +TIMER_CALLBACK_MEMBER(tmpz84c015_device::watchdog_timeout) +{ + if (!m_wdtout_cb.isnull()) + m_wdtout_cb(ASSERT_LINE); + else + logerror("Watchdog timeout\n"); +} + + void tmpz84c015_device::device_add_mconfig(machine_config &config) { /* basic machine hardware */ |