mame/src/devices/bus/thomson/cd90_351.cpp

496 lines
12 KiB
C++

// license:BSD-3-Clause
// copyright-holders:Olivier Galibert
// CD 90-351 - Custom floppy drive controller (THMFC1)
//
// Handles up to two 3.5 dual-sided drives (DD 90-352)
// or up to two 2.8 dual-sided QDD drivers (QD 90-280)
#include "emu.h"
#include "cd90_351.h"
#include "formats/thom_dsk.h"
DEFINE_DEVICE_TYPE(CD90_351, cd90_351_device, "cd90_351", "Thomson CD90-351 floppy drive controller")
cd90_351_device::cd90_351_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
device_t(mconfig, CD90_351, tag, owner, 16000000),
thomson_extension_interface(mconfig, *this),
m_floppy(*this, "%u", 0U),
m_rom(*this, "rom"),
m_rom_bank(*this, "rom_bank")
{
}
ROM_START(cd90_351)
// Rom has been dumped from the system, so the unaccessible ranges are
// missing (and probably totally unimportant)
ROM_REGION( 0x2000, "rom", 0 )
ROM_LOAD ( "cd-351-0.rom", 0x0000, 0x7c0, CRC(2c0159fd) SHA1(bab5395ed8bc7c06f9897897f836054e6546e8e8) )
ROM_LOAD ( "cd-351-1.rom", 0x0800, 0x7c0, CRC(8e58d159) SHA1(dcf992c96e7556b2faee6bacd3f744e56998e6ea) )
ROM_LOAD ( "cd-351-2.rom", 0x1000, 0x7c0, CRC(c9228b60) SHA1(179e10107d5be91e684069dee80f94847b83201f) )
ROM_LOAD ( "cd-351-3.rom", 0x1800, 0x7c0, CRC(3ca8e5dc) SHA1(7118636fb5c597c78c2fce17b02aed5e4ba38635) )
ROM_END
void cd90_351_device::rom_map(address_map &map)
{
map(0x000, 0x7bf).bankr(m_rom_bank);
}
void cd90_351_device::io_map(address_map &map)
{
map(0, 0).rw(FUNC(cd90_351_device::stat0_r), FUNC(cd90_351_device::cmd0_w));
map(1, 1).rw(FUNC(cd90_351_device::stat1_r), FUNC(cd90_351_device::cmd1_w));
map(2, 2).w(FUNC(cd90_351_device::cmd2_w));
map(3, 3).rw(FUNC(cd90_351_device::rdata_r), FUNC(cd90_351_device::wdata_w));
map(4, 4).w(FUNC(cd90_351_device::wclk_w));
map(5, 5).w(FUNC(cd90_351_device::wsect_w));
map(6, 6).w(FUNC(cd90_351_device::wtrck_w));
map(7, 7).w(FUNC(cd90_351_device::wcell_w));
map(8, 8).w(FUNC(cd90_351_device::bank_w));
}
const tiny_rom_entry *cd90_351_device::device_rom_region() const
{
return ROM_NAME(cd90_351);
}
void cd90_351_device::floppy_drives(device_slot_interface &device)
{
device.option_add("dd90_352", FLOPPY_35_DD);
// device.option_add("qd90_280", FLOPPY_28_QDD);
}
void cd90_351_device::floppy_formats(format_registration &fr)
{
fr.add_pc_formats();
fr.add(FLOPPY_THOMSON_35_FORMAT);
}
void cd90_351_device::device_add_mconfig(machine_config &config)
{
FLOPPY_CONNECTOR(config, m_floppy[0], floppy_drives, "dd90_352", floppy_formats).enable_sound(true);
FLOPPY_CONNECTOR(config, m_floppy[1], floppy_drives, nullptr, floppy_formats).enable_sound(true);
}
void cd90_351_device::device_start()
{
m_rom_bank->configure_entries(0, 4, m_rom->base(), 0x800);
m_timer_motoroff = timer_alloc(ID_MOTOROFF);
save_item(NAME(m_cmd0));
save_item(NAME(m_cmd1));
save_item(NAME(m_cmd2));
save_item(NAME(m_stat0));
save_item(NAME(m_data));
save_item(NAME(m_clk));
save_item(NAME(m_sect));
save_item(NAME(m_trck));
save_item(NAME(m_cell));
save_item(NAME(m_last_sync));
save_item(NAME(m_window_start));
save_item(NAME(m_shift_reg));
save_item(NAME(m_crc));
save_item(NAME(m_bit_counter));
save_item(NAME(m_data_reg));
save_item(NAME(m_data_separator_phase));
}
void cd90_351_device::device_reset()
{
m_rom_bank->set_entry(0);
m_cmd0 = 0;
m_cmd1 = 0;
m_cmd2 = 0;
m_stat0 = S0_FREE;
m_data = 0;
m_clk = 0;
m_sect = 0;
m_trck = 0;
m_cell = 0;
m_last_sync = 0;
m_window_start = 0;
m_shift_reg = 0;
m_crc = 0;
m_bit_counter = 0;
m_data_reg = 0;
m_data_separator_phase = false;
m_state = S_IDLE;
m_cur_floppy = nullptr;
}
void cd90_351_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
switch(id) {
case ID_MOTOROFF:
logerror("motor off\n");
if(m_cur_floppy)
m_cur_floppy->mon_w(1);
break;
}
}
void cd90_351_device::device_post_load()
{
if(m_cmd2 & C2_DRS0)
m_cur_floppy = m_floppy[0]->get_device();
else if(m_cmd2 & C2_DRS1)
m_cur_floppy = m_floppy[1]->get_device();
else
m_cur_floppy = nullptr;
}
void cd90_351_device::cmd0_w(u8 data)
{
sync();
static const char *const mode[4] = { "reset", "wsect", "rhead", "rsect" };
m_cmd0 = data;
logerror("cmd0_w %02x, code=%s, ensyn=%d nomck=%d wgc=%d mode=%s\n", m_cmd1,
m_cmd0 & C0_FM ? "fm" : "mfm",
m_cmd0 & C0_ENSYN ? 1 : 0,
m_cmd0 & C0_NOMCK ? 1 : 0,
m_cmd0 & C0_WGC ? 1 : 0,
mode[m_cmd0 & 3]);
if(m_stat0 & S0_FREE)
switch(m_cmd0 & 3) {
case 0:
break;
case 1:
logerror("wsect\n");
exit(0);
case 2:
logerror("rhead\n");
exit(0);
case 3:
logerror("read_sector start h=%d t=%2d s=%2d sz=%d\n",
m_cmd1 & C1_SIDE ? 1 : 0,
m_trck,
m_sect,
128 << ((m_cmd1 >> 5) & 3));
m_state = S_WAIT_HEADER_SYNC;
m_stat0 &= ~S0_FREE;
m_window_start = m_last_sync;
break;
}
}
void cd90_351_device::cmd1_w(u8 data)
{
sync();
m_cmd1 = data;
logerror("cmd1_w %02x, sector=(size=%d, side=%d) precomp=%d sync_only_when_ready=%s\n", m_cmd1,
128 << ((m_cmd1 >> 5) & 3),
m_cmd1 & C1_SIDE ? 1 : 0,
(m_cmd1 >> 1) & 7,
m_cmd1 & C1_DSYRD ? "on" : "off");
}
void cd90_351_device::cmd2_w(u8 data)
{
sync();
u8 prev = m_cmd2;
m_cmd2 = data;
logerror("cmd2_w %02x, side=%d dir=%d step=%d motor=%s sel=%c%c\n", m_cmd2,
m_cmd2 & C2_SISELB ? 1 : 0,
m_cmd2 & C2_DIRECB ? 1 : 0,
m_cmd2 & C2_STEP ? 1 : 0,
m_cmd2 & C2_MTON ? "on" : "off",
m_cmd2 & C2_DRS1 ? 'b' : '-',
m_cmd2 & C2_DRS0 ? 'a' : '-');
if(m_cmd2 & C2_DRS0)
m_cur_floppy = m_floppy[0]->get_device();
else if(m_cmd2 & C2_DRS1)
m_cur_floppy = m_floppy[1]->get_device();
else
m_cur_floppy = nullptr;
if(m_cur_floppy) {
if((prev & C2_MTON) && !(m_cmd2 & C2_MTON))
m_timer_motoroff->adjust(attotime::from_seconds(2));
if(m_cmd2 & C2_MTON) {
m_cur_floppy->mon_w(0);
m_timer_motoroff->adjust(attotime::never);
}
m_cur_floppy->ss_w(m_cmd2 & C2_SISELB ? 0 : 1);
m_cur_floppy->dir_w(m_cmd2 & C2_DIRECB ? 0 : 1);
m_cur_floppy->stp_w(m_cmd2 & C2_STEP ? 0 : 1);
}
}
void cd90_351_device::wdata_w(u8 data)
{
m_data = data;
m_stat0 &= ~(S0_BYTE | S0_DREQ);
logerror("wdata_w %02x\n", data);
}
void cd90_351_device::wclk_w(u8 data)
{
sync();
m_clk = data;
logerror("wclk_w %02x\n", data);
}
void cd90_351_device::wsect_w(u8 data)
{
sync();
m_sect = data;
logerror("wsect_w %02x\n", data);
}
void cd90_351_device::wtrck_w(u8 data)
{
sync();
m_trck = data;
logerror("wtrck_w %02x\n", data);
}
void cd90_351_device::wcell_w(u8 data)
{
sync();
m_cell = data;
logerror("wcell_w %02x\n", data);
}
u8 cd90_351_device::stat0_r()
{
if(!machine().side_effects_disabled()) {
sync();
static int ps = -1;
if(m_stat0 != ps)
logerror("stat0_r %02x -%s%s%s%s%s%s\n", m_stat0,
m_stat0 & S0_BYTE ? " byte" : "",
m_stat0 & S0_END ? " end" : "",
m_stat0 & S0_FREE ? " free" : "",
m_stat0 & S0_CRCER ? " crcer" : "",
m_stat0 & S0_DREQ ? " dreq" : "",
m_stat0 & S0_SYNC ? " sync" : "");
ps = m_stat0;
}
return m_stat0;
}
u8 cd90_351_device::stat1_r()
{
u8 res = 0;
if(m_cur_floppy) {
if(m_cur_floppy->idx_r())
res |= S1_INDX;
if(!m_cur_floppy->dskchg_r())
res |= S1_DKCH;
if(!m_cur_floppy->mon_r())
res |= S1_MTON;
if(!m_cur_floppy->trk00_r())
res |= S1_TRK0;
if(!m_cur_floppy->wpt_r())
res |= S1_WPRT;
if(!m_cur_floppy->ready_r())
res |= S1_RDY;
}
if(!machine().side_effects_disabled())
logerror("stat1_r %02x -%s%s%s%s%s%s\n", res,
res & S1_INDX ? " index" : "",
res & S1_DKCH ? " dskchg" : "",
res & S1_MTON ? " mton" : "",
res & S1_TRK0 ? " trk0" : "",
res & S1_WPRT ? " wprt" : "",
res & S1_RDY ? " ready" : "");
return res;
}
u8 cd90_351_device::rdata_r()
{
if(!machine().side_effects_disabled())
m_stat0 &= ~(S0_BYTE | S0_DREQ);
return m_data;
}
void cd90_351_device::bank_w(u8 data)
{
logerror("bank_w %d\n", data & 3);
m_rom_bank->set_entry(data & 3);
}
u64 cd90_351_device::time_to_cycles(const attotime &tm) const
{
return tm.as_ticks(clock());
}
attotime cd90_351_device::cycles_to_time(u64 cycles) const
{
return attotime::from_ticks(cycles, clock());
}
bool cd90_351_device::read_one_bit(u64 limit, u64 &next_flux_change)
{
while(next_flux_change <= m_last_sync) {
attotime flux = m_cur_floppy ? m_cur_floppy->get_next_transition(cycles_to_time(m_last_sync+1)) : attotime::never;
next_flux_change = flux.is_never() ? u64(-1) : time_to_cycles(flux);
}
u64 window_end = m_window_start + (m_cell & 0x7f);
if(window_end > limit)
return true;
int bit = next_flux_change < window_end;
if(bit && (m_cmd0 & C0_NOMCK))
m_window_start = next_flux_change + ((m_cell & 0x7f) >> 1);
else
m_window_start = window_end;
m_last_sync = window_end;
m_shift_reg = (m_shift_reg << 1) | bit;
m_bit_counter++;
if(m_data_separator_phase) {
m_data_reg = (m_data_reg << 1) | bit;
if((m_crc ^ (bit ? 0x8000 : 0x0000)) & 0x8000)
m_crc = (m_crc << 1) ^ 0x1021;
else
m_crc = m_crc << 1;
}
m_data_separator_phase = !m_data_separator_phase;
return false;
}
u8 cd90_351_device::clk_bits() const
{
return
(m_shift_reg & 0x8000 ? 0x80 : 0x00) |
(m_shift_reg & 0x2000 ? 0x40 : 0x00) |
(m_shift_reg & 0x0800 ? 0x20 : 0x00) |
(m_shift_reg & 0x0200 ? 0x10 : 0x00) |
(m_shift_reg & 0x0080 ? 0x08 : 0x00) |
(m_shift_reg & 0x0020 ? 0x04 : 0x00) |
(m_shift_reg & 0x0008 ? 0x02 : 0x00) |
(m_shift_reg & 0x0002 ? 0x01 : 0x00);
}
void cd90_351_device::sync()
{
u64 next_sync = machine().time().as_ticks(clock());
u64 next_flux_change = 0;
while(m_last_sync < next_sync)
switch(m_state) {
case S_IDLE:
m_last_sync = next_sync;
break;
case S_WAIT_HEADER_SYNC: {
if(read_one_bit(next_sync, next_flux_change))
return;
if(m_shift_reg == 0xaaaa) {
m_crc = 0xffff;
m_data_separator_phase = false;
}
if(m_data_reg == m_data && clk_bits() == m_clk) {
m_bit_counter = 0;
m_state = S_VERIFY_HEADER;
}
break;
}
case S_VERIFY_HEADER: {
if(read_one_bit(next_sync, next_flux_change))
return;
if(m_bit_counter & 0xf)
break;
bool valid = true;
switch(m_bit_counter >> 4) {
case 1:
case 2:
valid = m_data_reg == m_data && clk_bits() == m_clk;
break;
case 3:
valid = m_data_reg == 0xfe;
break;
case 4:
valid = m_data_reg == m_trck;
break;
case 5:
valid = (m_data_reg & 1) == (m_cmd1 & C1_SIDE ? 1 : 0);
break;
case 6:
valid = m_data_reg == m_sect;
break;
case 7:
valid = (m_data_reg & 3) == ((m_cmd1 >> 5) & 3);
break;
// 8 skipped
case 9:
valid = m_crc == 0;
m_bit_counter = 0;
m_state = S_SKIP_GAP;
break;
}
if(!valid)
m_state = S_WAIT_HEADER_SYNC;
break;
}
case S_SKIP_GAP:
if(read_one_bit(next_sync, next_flux_change))
return;
if(m_bit_counter == 27 << 4) {
m_bit_counter = 0;
m_state = S_WAIT_SECTOR_SYNC;
}
break;
case S_WAIT_SECTOR_SYNC: {
if(read_one_bit(next_sync, next_flux_change))
return;
if(m_shift_reg == 0xaaaa) {
m_crc = 0xffff;
m_data_separator_phase = false;
}
if(m_data_reg == m_data && clk_bits() == m_clk) {
m_bit_counter = 0;
m_data = m_data_reg;
m_stat0 |= S0_DREQ;
m_state = S_READ_SECTOR;
}
if(m_bit_counter == 42 << 4)
m_state = S_WAIT_HEADER_SYNC;
break;
}
case S_READ_SECTOR:
if(read_one_bit(next_sync, next_flux_change))
return;
if(m_bit_counter != 16)
break;
if(m_stat0 & (S0_BYTE|S0_DREQ)) {
logerror("read_sector end\n");
if(m_crc)
m_stat0 |= S0_CRCER;
m_stat0 &= ~S0_BYTE;
m_stat0 |= S0_FREE;
m_cmd0 &= ~3;
m_state = S_IDLE;
break;
}
m_stat0 |= S0_BYTE;
m_data = m_data_reg;
m_bit_counter = 0;
break;
}
}