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// license:BSD-3-Clause
// copyright-holders:smf
#include "emu.h"
#include "ds128x.h"
DEFINE_DEVICE_TYPE(DS12885, ds12885_device, "ds12885", "DS12885 RTC/NVRAM")
//-------------------------------------------------
// ds12885_device - constructor
//-------------------------------------------------
ds12885_device::ds12885_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: ds12885_device(mconfig, DS12885, tag, owner, clock)
{
}
ds12885_device::ds12885_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock)
: mc146818_device(mconfig, type, tag, owner, clock)
{
}
int ds12885_device::get_timer_bypass() const
{
if( !( m_data[REG_A] & REG_A_DV0 ) ) //DV0 must be 0 for timekeeping
{
return 7; // Fixed at 1 Hz with clock at 32768Hz
}
return 22; // No tick
}
DEFINE_DEVICE_TYPE(DS12885EXT, ds12885ext_device, "ds12885ext", "DS12885 RTC/NVRAM size 256 bytes")
//-------------------------------------------------
// ds12885ext_device - constructor
//-------------------------------------------------
ds12885ext_device::ds12885ext_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: ds12885_device(mconfig, DS12885EXT, tag, owner, clock)
{
}
//-------------------------------------------------
// ds12885ext_device - handlers that allow acces to extended memory size
//-------------------------------------------------
uint8_t ds12885ext_device::read_extended(offs_t offset)
{
switch (offset)
{
case 0:
case 2:
return get_address();
case 1:
case 3:
return data_r();
break;
default:
return 0xff;
}
}
void ds12885ext_device::write_extended(offs_t offset, uint8_t data)
{
switch (offset)
{
case 0:
address_w(data & 127);
break;
case 1:
data_w(data);
break;
case 2:
address_w(data);
break;
case 3:
data_w(data);
break;
}
}
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