static WRITE8_HANDLER( svi318_fdc_density_side_w )
{
device_t *fdc = space->machine().device("wd179x");
wd17xx_dden_w(fdc, BIT(data, 0));
wd17xx_set_side(fdc, BIT(data, 1));
}
void coco_fdc_device::dskreg_w(UINT8 data)
{
UINT8 drive = 0;
UINT8 head = 0;
if (LOG_FDC)
{
logerror("fdc_coco_dskreg_w(): %c%c%c%c%c%c%c%c ($%02x)\n",
data & 0x80 ? 'H' : 'h',
data & 0x40 ? '3' : '.',
data & 0x20 ? 'D' : 'S',
data & 0x10 ? 'P' : 'p',
data & 0x08 ? 'M' : 'm',
data & 0x04 ? '2' : '.',
data & 0x02 ? '1' : '.',
data & 0x01 ? '0' : '.',
data);
}
/* An email from John Kowalski informed me that if the DS3 is
* high, and one of the other drive bits is selected (DS0-DS2), then the
* second side of DS0, DS1, or DS2 is selected. If multiple bits are
* selected in other situations, then both drives are selected, and any
* read signals get yucky.
*/
if (data & 0x04)
drive = 2;
else if (data & 0x02)
drive = 1;
else if (data & 0x01)
drive = 0;
else if (data & 0x40)
drive = 3;
device_t *floppy[4];
floppy[0] = subdevice(FLOPPY_0);
floppy[1] = subdevice(FLOPPY_1);
floppy[2] = subdevice(FLOPPY_2);
floppy[3] = subdevice(FLOPPY_3);
for (int i = 0; i < 4; i++)
{
floppy_mon_w(floppy[i], i == drive ? CLEAR_LINE : ASSERT_LINE);
}
head = ((data & 0x40) && (drive != 3)) ? 1 : 0;
m_dskreg = data;
update_lines();
wd17xx_set_drive(m_wd17xx, drive);
wd17xx_set_side(m_wd17xx, head);
wd17xx_dden_w(m_wd17xx, !BIT(m_dskreg, 5));
}
static void duart_output(device_t *device, UINT8 data)
{
device_t *fdc = device->machine().device("wd1770");
wd17xx_set_side(fdc,BIT(data,3) ? 0 : 1);
if (BIT(data,7)==0) {
wd17xx_set_drive(fdc,0);
} else if (BIT(data,6)==0) {
wd17xx_set_drive(fdc,1);
} else if (BIT(data,5)==0) {
wd17xx_set_drive(fdc,2);
} else if (BIT(data,4)==0) {
wd17xx_set_drive(fdc,3);
}
}
void comx_fd_device::comx_io_w(offs_t offset, UINT8 data)
{
if (offset == 2)
{
if (m_q)
{
/*
bit description
0 A0
1 A1
2 DRIVE0
3 DRIVE1
4 F9 DISB
5 SIDE SELECT
*/
// latch data to F3
m_addr = data & 0x03;
if (BIT(data, 2))
{
wd17xx_set_drive(m_fdc, 0);
}
else if (BIT(data, 3))
{
wd17xx_set_drive(m_fdc, 1);
}
m_disb = !BIT(data, 4);
update_ef4();
wd17xx_set_side(m_fdc, BIT(data, 5));
}
else
{
// write data to WD1770
wd17xx_w(m_fdc, m_addr, data);
}
}
}
static WRITE8_DEVICE_HANDLER( cru_w )
{
ti99_fdc_state *card = get_safe_token(device);
int drive, drivebit;
if ((offset & 0xff00)==CRU_BASE)
{
int bit = (offset >> 1) & 0x07;
switch (bit)
{
case 0:
/* (De)select the card. Indicated by a LED on the board. */
card->selected = data;
break;
case 1:
/* Activate motor */
if (data && !card->strobe_motor)
{ /* on rising edge, set motor_running for 4.23s */
card->DVENA = TRUE;
fdc_handle_hold(device);
card->motor_on_timer->adjust(attotime::from_msec(4230));
}
card->strobe_motor = data;
break;
case 2:
/* Set disk ready/hold (bit 2) */
// 0: ignore IRQ and DRQ
// 1: TMS9900 is stopped until IRQ or DRQ are set
// OR the motor stops rotating - rotates for 4.23s after write
// to CRU bit 1
// This is not emulated and could cause the TI99 to lock up
card->hold = data;
fdc_handle_hold(device);
break;
case 3:
/* Load disk heads (HLT pin) (bit 3). Not implemented. */
break;
case 4:
case 5:
case 6:
/* Select drive X (bits 4-6) */
drive = bit-4; /* drive # (0-2) */
drivebit = 1<<drive;
if (data)
{
if (!(card->DSEL & drivebit)) /* select drive */
{
if (card->DSEL != 0)
logerror("ti_fdc: Multiple drives selected, %02x\n", card->DSEL);
card->DSEL |= drivebit;
wd17xx_set_drive(card->controller, drive);
/*wd17xx_set_side(DSKside);*/
}
}
else
card->DSEL &= ~drivebit;
break;
case 7:
/* Select side of disk (bit 7) */
card->SIDSEL = data;
wd17xx_set_side(card->controller, data);
break;
}
}
