// license:BSD-3-Clause
// copyright-holders:smf,Barry Rodewald
/***************************************************************************
x2212.c
Xicor X2212 256 x 4 bit Nonvolatile Static RAM.
***************************************************************************/
#include "emu.h"
#include "machine/x2212.h"
//**************************************************************************
// GLOBAL VARIABLES
//**************************************************************************
static ADDRESS_MAP_START( x2212_sram_map, AS_0, 8, x2212_device )
AM_RANGE(0x0000, 0x00ff) AM_RAM
ADDRESS_MAP_END
static ADDRESS_MAP_START( x2212_e2prom_map, AS_1, 8, x2212_device )
AM_RANGE(0x0000, 0x00ff) AM_RAM
ADDRESS_MAP_END
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
// device type definition
const device_type X2212 = device_creator<x2212_device>;
const device_type X2210 = device_creator<x2210_device>;
//-------------------------------------------------
// x2212_device - constructor
//-------------------------------------------------
x2212_device::x2212_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, X2212, "X2212 NVRAM", tag, owner, clock, "x2212", __FILE__),
device_memory_interface(mconfig, *this),
device_nvram_interface(mconfig, *this),
m_auto_save(false),
m_sram_space_config("SRAM", ENDIANNESS_BIG, 8, 8, 0, *ADDRESS_MAP_NAME(x2212_sram_map)),
m_e2prom_space_config("E2PROM", ENDIANNESS_BIG, 8, 8, 0, *ADDRESS_MAP_NAME(x2212_e2prom_map)),
m_store(false),
m_array_recall(false),
m_size_data(0x100),
m_default_data(*this, DEVICE_SELF, 0x100)
{
}
x2212_device::x2212_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, uint32_t clock, const char *shortname, const char *source, int size_data)
: device_t(mconfig, type, name, tag, owner, clock, shortname, source),
device_memory_interface(mconfig, *this),
device_nvram_interface(mconfig, *this),
m_auto_save(false),
m_sram_space_config("SRAM", ENDIANNESS_BIG, 8, 8, 0, *ADDRESS_MAP_NAME(x2212_sram_map)),
m_e2prom_space_config("E2PROM", ENDIANNESS_BIG, 8, 8, 0, *ADDRESS_MAP_NAME(x2212_e2prom_map)),
m_store(false),
m_array_recall(false),
m_size_data(size_data),
m_default_data(*this, DEVICE_SELF, size_data)
{
}
//-------------------------------------------------
// static_set_auto_save - configuration helper
// to set the auto-save flag
//-------------------------------------------------
void x2212_device::static_set_auto_save(device_t &device)
{
downcast<x2212_device &>(device).m_auto_save = true;
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void x2212_device::device_start()
{
save_item(NAME(m_store));
save_item(NAME(m_array_recall));
m_sram = &space(AS_0);
m_e2prom = &space(AS_1);
}
//-------------------------------------------------
// memory_space_config - return a description of
// any address spaces owned by this device
//-------------------------------------------------
const address_space_config *x2212_device::memory_space_config(address_spacenum spacenum) const
{
return (spacenum == 0) ? &m_sram_space_config : (spacenum == 1) ? &m_e2prom_space_config : nullptr;
}
//-------------------------------------------------
// nvram_default - called to initialize NVRAM to
// its default state
//-------------------------------------------------
void x2212_device::nvram_default()
{
// default to all-0xff
for (int byte = 0; byte < m_size_data; byte++)
{
m_sram->write_byte(byte, 0xff);
m_e2prom->write_byte(byte, 0xff);
}
// populate from a memory region if present
if (m_default_data.found())
{
for (int byte = 0; byte < m_size_data; byte++)
m_e2prom->write_byte(byte, m_default_data[byte]);
}
}
//-------------------------------------------------
// nvram_read - called to read NVRAM from the
// .nv file
//-------------------------------------------------
void x2212_device::nvram_read(emu_file &file)
{
uint8_t *buffer = (uint8_t *) alloca(m_size_data);
file.read(buffer, m_size_data);
for (int byte = 0; byte < m_size_data; byte++)
{
m_sram->write_byte(byte, 0xff);
m_e2prom->write_byte(byte, buffer[byte]);
}
}
//-------------------------------------------------
// nvram_write - called to write NVRAM to the
// .nv file
//-------------------------------------------------
void x2212_device::nvram_write(emu_file &file)
{
// auto-save causes an implicit store prior to exiting (writing)
if (m_auto_save)
store();
uint8_t *buffer = (uint8_t *) alloca(m_size_data);
for (int byte = 0; byte < m_size_data; byte++)
buffer[byte] = m_e2prom->read_byte(byte);
file.write(buffer, m_size_data);
}
//**************************************************************************
// INTERNAL HELPERS
//**************************************************************************
//-------------------------------------------------
// store - store data from live RAM into the
// EEPROM
//-------------------------------------------------
void x2212_device::store()
{
for (int byte = 0; byte < m_size_data; byte++)
m_e2prom->write_byte(byte, m_sram->read_byte(byte));
}
//-------------------------------------------------
// recall - fetch data from the EEPROM into live
// RAM
//-------------------------------------------------
void x2212_device::recall()
{
for (int byte = 0; byte < m_size_data; byte++)
m_sram->write_byte(byte, m_e2prom->read_byte(byte));
}
//**************************************************************************
// READ/WRITE HANDLERS
//**************************************************************************
//-------------------------------------------------
// write - store to the live RAM
//-------------------------------------------------
WRITE8_MEMBER( x2212_device::write )
{
m_sram->write_byte(offset, data & 0x0f);
}
//-------------------------------------------------
// read - read from the live RAM
//-------------------------------------------------
READ8_MEMBER( x2212_device::read )
{
return (m_sram->read_byte(offset) & 0x0f) | (space.unmap() & 0xf0);
}
//-------------------------------------------------
// store - set the state of the store line
// (active high)
//-------------------------------------------------
WRITE_LINE_MEMBER( x2212_device::store )
{
if (state != 0 && !m_store)
store();
m_store = (state != 0);
}
//-------------------------------------------------
// recall - set the state of the recall line
// (active high)
//-------------------------------------------------
WRITE_LINE_MEMBER( x2212_device::recall )
{
if (state != 0 && !m_array_recall)
recall();
m_array_recall = (state != 0);
}
x2210_device::x2210_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: x2212_device(mconfig, X2210, "X2210", tag, owner, clock, "x2210", __FILE__, 0x40)
{
}