// license:BSD-3-Clause
// copyright-holders:Miodrag Milanovic
/***************************************************************************
Chips & Technologies CS8221 chipset
a.k.a. NEW ENHANCED AT (NEAT)
Consists of four individual chips:
* 82C211 - CPU/Bus controller
* 82C212 - Page/Interleave and EMS Memory controller
* 82C215 - Data/Address buffer
* 82C206 - Integrated Peripherals Controller(IPC)
***************************************************************************/
#include "emu.h"
#include "cs8221.h"
#include "machine/ram.h"
#define LOG_REGISTER (1U << 1)
#define LOG_MEMORY (1U << 2)
#define VERBOSE (LOG_REGISTER | LOG_MEMORY)
#include "logmacro.h"
#define LOGREGISTER(...) LOGMASKED(LOG_REGISTER, __VA_ARGS__)
#define LOGMEMORY(...) LOGMASKED(LOG_MEMORY, __VA_ARGS__)
DEFINE_DEVICE_TYPE(CS8221, cs8221_device, "cs8221", "CS8221 NEAT")
static const char *const register_names[] =
{
/* 00 */ "PROCCLK",
/* 01 */ "COMMAND DELAY",
/* 02 */ "WAIT STATES",
/* 03 */ "RESERVED",
/* 04 */ "VERSION",
/* 05 */ "ROM CONFIGURATION",
/* 06 */ "MEMORY ENABLE-1",
/* 07 */ "MEMORY ENABLE-2",
/* 08 */ "MEMORY ENABLE-3",
/* 09 */ "MEMORY ENABLE-4",
/* 0a */ "BANK 0/1 ENABLE",
/* 0b */ "DRAM CONFIGURATION",
/* 0c */ "BANK 2/3 ENABLE",
/* 0d */ "EMS BASE ADDRESS",
/* 0e */ "EMS ADDRESS EXTENSION",
/* 0f */ "MISCELLANEOUS"
};
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
//-------------------------------------------------
// cs8221_device - constructor
//-------------------------------------------------
cs8221_device::cs8221_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, CS8221, tag, owner, clock),
m_address(0),
m_address_valid(false)
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void cs8221_device::device_start()
{
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void cs8221_device::device_reset()
{
// setup default values
memset(&m_registers, 0x00, sizeof(m_registers));
}
//**************************************************************************
// READ/WRITE HANDLERS
//**************************************************************************
void cs8221_device::map(address_map &map)
{
map(0x0022, 0x0022).w("cs8221", FUNC(cs8221_device::address_w));
map(0x0023, 0x0023).rw("cs8221", FUNC(cs8221_device::data_r), FUNC(cs8221_device::data_w));
}
void cs8221_device::address_w(uint8_t data)
{
m_address = data;
m_address_valid = ((m_address & 0x60)== 0x60) ? true : false;
}
uint8_t cs8221_device::data_r()
{
uint8_t result = 0xff;
if (m_address_valid)
{
LOGREGISTER("cs8221_device: read %s = %02x\n", register_names[m_address & 0x0f], m_registers[m_address & 0x0f]);
result = m_registers[m_address & 0x0f];
}
// after a read the selected address needs to be reset
m_address_valid = false;
return result;
}
void cs8221_device::data_w(uint8_t data)
{
if (m_address_valid)
{
LOGREGISTER("cs8221_device: write %s = %02x\n", register_names[m_address & 0x0f], data);
// update register with new data
m_registers[m_address & 0x0f] = data;
// execute command
switch (m_address)
{
case 0x60: break;
case 0x61: break;
case 0x62: break;
case 0x63: break;
case 0x64: break;
case 0x65: break;
case 0x66: break;
case 0x67: break;
case 0x68: break;
case 0x69: break;
case 0x6a: break;
case 0x6b: break;
case 0x6c: break;
case 0x6d: break;
case 0x6e: break;
case 0x6f: break;
}
}
// after a write the selected address needs to be reset
m_address_valid = false;
}