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(MESS) c2040: Fixed READY signal. (nw)

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This commit is contained in:
Curt Coder 2014-02-09 21:52:06 +00:00
parent caae1567b6
commit e187bc4a43
2 changed files with 27 additions and 22 deletions
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48
src/emu/bus/ieee488/c2040fdc.c
View File

@ -14,8 +14,6 @@
TODO:
- writing starts in the middle of a byte
- READY output is actually low when (CNT=9 QB=0), but since we latch the read
byte on syncpoints, READY is low when (prevCNT=9 CNT=0) as seen below
- 8050 PLL
*/
@ -90,6 +88,8 @@ c2040_fdc_t::c2040_fdc_t(const machine_config &mconfig, device_type type, const
cur_live.tm = attotime::never;
cur_live.state = IDLE;
cur_live.next_state = -1;
cur_live.write_position = 0;
cur_live.write_start_time = attotime::never;
}
c2040_fdc_t::c2040_fdc_t(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
@ -113,6 +113,8 @@ c2040_fdc_t::c2040_fdc_t(const machine_config &mconfig, const char *tag, device_
cur_live.tm = attotime::never;
cur_live.state = IDLE;
cur_live.next_state = -1;
cur_live.write_position = 0;
cur_live.write_start_time = attotime::never;
}
c8050_fdc_t::c8050_fdc_t(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
@ -133,6 +135,16 @@ void c2040_fdc_t::device_start()
// allocate timer
t_gen = timer_alloc(0);
// register for state saving
save_item(NAME(m_mtr0));
save_item(NAME(m_mtr1));
save_item(NAME(m_stp0));
save_item(NAME(m_stp1));
save_item(NAME(m_ds));
save_item(NAME(m_drv_sel));
save_item(NAME(m_mode_sel));
save_item(NAME(m_rw_sel));
}
@ -327,8 +339,6 @@ void c2040_fdc_t::live_run(attotime limit)
cur_live.cell_counter &= 0xf;
}
int ready = cur_live.ready;
if (!BIT(cell_counter, 1) && BIT(cur_live.cell_counter, 1)) {
// read bit
cur_live.shift_reg <<= 1;
@ -343,22 +353,20 @@ void c2040_fdc_t::live_run(attotime limit)
write_next_bit(BIT(cur_live.shift_reg_write, 9), limit);
}
// update bit counter
if ((cur_live.shift_reg == 0x3ff) && cur_live.rw_sel) {
cur_live.bit_counter = 0;
} else {
cur_live.bit_counter++;
if (cur_live.bit_counter == 10) {
cur_live.bit_counter = 0;
ready = 0;
} else {
ready = 1;
}
}
syncpoint = true;
}
int sync = !((cur_live.shift_reg == 0x3ff) && cur_live.rw_sel);
if (!sync) {
cur_live.bit_counter = 0;
} else if (!BIT(cell_counter, 1) && BIT(cur_live.cell_counter, 1) && cur_live.sync) {
cur_live.bit_counter++;
if (cur_live.bit_counter == 10) {
cur_live.bit_counter = 0;
}
}
// update GCR
if (cur_live.rw_sel) {
cur_live.i = (cur_live.rw_sel << 10) | cur_live.shift_reg;
@ -368,9 +376,7 @@ void c2040_fdc_t::live_run(attotime limit)
cur_live.e = m_gcr_rom->base()[cur_live.i];
if (BIT(cell_counter, 1) && !BIT(cur_live.cell_counter, 1) && cur_live.bit_counter == 9) {
//ready = 0;
}
int ready = !(BIT(cell_counter, 1) && !BIT(cur_live.cell_counter, 1) && (cur_live.bit_counter == 9));
if (!ready) {
// load write shift register
@ -389,8 +395,6 @@ void c2040_fdc_t::live_run(attotime limit)
if (LOG) logerror("%s write shift << %03x\n",cur_live.tm.as_string(),cur_live.shift_reg_write);
}
// update signals
int sync = !((cur_live.shift_reg == 0x3ff) && cur_live.rw_sel);
int error = !(BIT(cur_live.e, 3) || ready);
if (ready != cur_live.ready) {

1
src/emu/bus/ieee488/c2040fdc.h
View File

@ -64,6 +64,7 @@ public:
DECLARE_WRITE_LINE_MEMBER( mtr1_w );
DECLARE_WRITE_LINE_MEMBER( odd_hd_w );
DECLARE_WRITE_LINE_MEMBER( pull_sync_w );
DECLARE_READ_LINE_MEMBER( wps_r ) { return checkpoint_live.drv_sel ? m_floppy1->wpt_r() : m_floppy0->wpt_r(); }
DECLARE_READ_LINE_MEMBER( sync_r ) { return checkpoint_live.sync; }
DECLARE_READ_LINE_MEMBER( ready_r ) { return checkpoint_live.ready; }