mame/src/devices/cpu/sh2/sh7604_wdt.cpp
2016-09-27 18:36:59 +02:00

87 lines
2.5 KiB
C++

// license:BSD-3-Clause
// copyright-holders:Angelo Salese
/***************************************************************************
SH7604 Watchdog Timer Controller
TODO:
- Host CPU setter (clock and callback for irq and reset lines);
- memory map (needs to verify if ID write is ok);
***************************************************************************/
#include "emu.h"
#include "sh7604_wdt.h"
//**************************************************************************
// GLOBAL VARIABLES
//**************************************************************************
// device type definition
const device_type SH7604_WDT = &device_creator<sh7604_wdt_device>;
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
static ADDRESS_MAP_START( wdt_regs, AS_0, 8, sh7604_wdt_device )
// AM_RANGE(0x00, 0x00) timer control/status
// AM_RANGE(0x01, 0x01) timer counter
// AM_RANGE(0x02, 0x02) write only, reset control register
// AM_RANGE(0x03, 0x03) read status register, write reset status register
ADDRESS_MAP_END
//-------------------------------------------------
// sh7604_wdt_device - constructor
//-------------------------------------------------
sh7604_wdt_device::sh7604_wdt_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
: device_t(mconfig, SH7604_WDT, "sh7604_wdt_longname", tag, owner, clock, "sh7604_wdt", __FILE__),
device_memory_interface(mconfig, *this),
m_space_config("regs", ENDIANNESS_BIG, 8, 4, 0, nullptr, *ADDRESS_MAP_NAME(wdt_regs))
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void sh7604_wdt_device::device_start()
{
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void sh7604_wdt_device::device_reset()
{
}
//**************************************************************************
// READ/WRITE HANDLERS
//**************************************************************************
READ8_MEMBER( sh7604_wdt_device::read )
{
return space.read_byte(offset);
}
WRITE16_MEMBER( sh7604_wdt_device::write )
{
UINT8 id_param = data >> 8;
switch(id_param)
{
case 0xa5: space.write_byte(offset*2+0,data & 0xff); break;
case 0x5a: space.write_byte(offset*2+1,data & 0xff); break;
default: throw emu_fatalerror("%s: invalid id param write = %02x\n",tag(),id_param);
}
}