void pia6821_device::control_b_w(UINT8 data)
{
int temp;
// bit 7 and 6 are read only
data &= 0x3f;
LOG(("PIA #%s: control B write = %02X\n", tag(), data));
// update the control register
m_ctl_b = data;
if (C2_SET_MODE(m_ctl_b))
{
// set/reset mode - bit value determines the new output
temp = C2_SET(m_ctl_b);
}
else
{
// strobe mode - output is always high unless strobed
temp = TRUE;
}
set_out_cb2(temp);
// update externals
update_interrupts();
}
static void control_b_w(const device_config *device, UINT8 data)
{
pia6821_state *p = get_token(device);
int temp;
/* bit 7 and 6 are read only */
data &= 0x3f;
LOG(("PIA #%s: control B write = %02X\n", device->tag, data));
/* update the control register */
p->ctl_b = data;
if (C2_SET_MODE(p->ctl_b))
/* set/reset mode - bit value determines the new output */
temp = C2_SET(p->ctl_b);
else
/* strobe mode - output is always high unless strobed */
temp = TRUE;
set_out_cb2(device, temp);
/* update externals */
update_interrupts(device);
}
void pia6821_device::port_b_w(UINT8 data)
{
// buffer the output value
m_out_b = data;
send_to_out_b_func("port B write");
// CB2 in write strobe mode
if(C2_STROBE_MODE(m_ctl_b))
{
// this will cause a transition low
set_out_cb2(FALSE);
// if the CB2 strobe is cleared by the E, reset it right away
if(STROBE_E_RESET(m_ctl_b))
{
set_out_cb2(TRUE);
}
}
}
static void port_b_w(const device_config *device, UINT8 data)
{
pia6821_state *p = get_token(device);
/* buffer the output value */
p->out_b = data;
send_to_out_b_func(device, "port B write");
/* CB2 in write strobe mode */
if (C2_STROBE_MODE(p->ctl_b))
{
/* this will cause a transition low */
set_out_cb2(device, FALSE);
/* if the CB2 strobe is cleared by the E, reset it right away */
if (STROBE_E_RESET(p->ctl_b))
set_out_cb2(device, TRUE);
}
}
UINT8 pia6821_device::port_b_r()
{
UINT8 ret = get_in_b_value();
// This read will implicitly clear the IRQ B1 flag. If CB2 is in write-strobe
// mode with CB1 restore, and a CB1 active transition set the flag,
// clearing it will cause CB2 to go high again. Note that this is different
// from what happens with port A.
if(m_irq_b1 && C2_STROBE_MODE(m_ctl_b) && STROBE_C1_RESET(m_ctl_b))
{
set_out_cb2(TRUE);
}
// IRQ flags implicitly cleared by a read
m_irq_b1 = FALSE;
m_irq_b2 = FALSE;
update_interrupts();
LOG(("PIA #%s: port B read = %02X\n", tag(), ret));
return ret;
}
static UINT8 port_b_r(const device_config *device)
{
pia6821_state *p = get_token(device);
UINT8 ret = get_in_b_value(device);
/* This read will implicitly clear the IRQ B1 flag. If CB2 is in write-strobe
mode with CB1 restore, and a CB1 active transition set the flag,
clearing it will cause CB2 to go high again. Note that this is different
from what happens with port A. */
if (p->irq_b1 && C2_STROBE_MODE(p->ctl_b) && STROBE_C1_RESET(p->ctl_b))
set_out_cb2(device, TRUE);
/* IRQ flags implicitly cleared by a read */
p->irq_b1 = FALSE;
p->irq_b2 = FALSE;
update_interrupts(device);
LOG(("PIA #%s: port B read = %02X\n", device->tag, ret));
return ret;
}
