void pia_set_input_cb2 (int which, int data)
{
struct pia6821 *p = pia + which;
/* limit the data to 0 or 1 */
data = data ? 1 : 0;
/* CB2 is in input mode */
if (C2_INPUT (p->ctl_b))
{
/* the new state has caused a transition */
if (p->in_cb2 ^ data)
{
/* handle the active transition */
if ((data && C2_LOW_TO_HIGH (p->ctl_b)) || (!data && C2_HIGH_TO_LOW (p->ctl_b)))
{
/* mark the IRQ */
p->irq_b2 = 1;
/* call the IRQ function if enabled */
if (IRQ2_ENABLED (p->ctl_b))
if (p->irq_b_func) p->irq_b_func ();
}
}
}
/* set the new value for CA2 */
p->in_cb2 = data;
}
void pia_set_input_cb2(int which, int data)
{
struct pia6821 *p = pia + which;
/* limit the data to 0 or 1 */
data = data ? 1 : 0;
/* CB2 is in input mode */
if (C2_INPUT(p->ctl_b))
{
/* the new state has caused a transition */
if (p->in_cb2 ^ data)
{
/* handle the active transition */
if ((data && C2_LOW_TO_HIGH(p->ctl_b)) || (!data && C2_HIGH_TO_LOW(p->ctl_b)))
{
/* mark the IRQ */
p->irq_b2 = 1;
/* update externals */
update_6821_interrupts(p);
}
}
}
/* set the new value for CA2 */
p->in_cb2 = data;
p->in_set |= PIA_IN_SET_CB2;
}
void C6821::SetCB2(BYTE byData)
{
byData = byData ? 1 : 0;
// CA2 is in input mode
if ( C2_INPUT( m_byCTLB ) )
{
// the new state has caused a transition
if ( m_byICB2 ^ byData )
{
// handle the active transition
if ( ( byData && C2_LOW_TO_HIGH( m_byCTLB ) ) ||
( !byData && C2_HIGH_TO_LOW( m_byCTLB ) ) )
{
// mark the IRQ
SET_IRQ2( m_byCTLB );
// update externals
UpdateInterrupts();
}
}
}
// set the new value for CA2
m_byICB2 = byData;
}
int pia6821_device::ca2_output_z()
{
m_out_ca2_needs_pulled = false;
// If it's an output, output the bit, if it's an input, it's
// pulled up
return m_out_ca2 | C2_INPUT(m_ctl_a);
}
UINT8 pia6821_device::control_b_r()
{
UINT8 ret;
// update CB1 & CB2 if callback exists, these in turn may update IRQ's
if(!m_in_cb1_func.isnull())
{
cb1_w(m_in_cb1_func());
}
else if(!m_logged_cb1_not_connected && !m_in_cb1_pushed)
{
logerror("PIA #%s: Error! no CB1 read handler. Three-state pin is undefined\n", tag());
m_logged_cb1_not_connected = true;
}
if(!m_in_cb2_func.isnull())
{
cb2_w(m_in_cb2_func());
}
else if(!m_logged_cb2_not_connected && C2_INPUT(m_ctl_b) && !m_in_cb2_pushed)
{
logerror("PIA #%s: Error! No CB2 read handler. Three-state pin is undefined\n", tag());
m_logged_cb2_not_connected = true;
}
// read control register
ret = m_ctl_b;
// set the IRQ flags if we have pending IRQs
if(m_irq_b1)
{
ret |= PIA_IRQ1;
}
if(m_irq_b2 && C2_INPUT(m_ctl_b))
{
ret |= PIA_IRQ2;
}
LOG(("PIA #%s: control B read = %02X\n", tag(), ret));
return ret;
}
UINT8 pia6821_device::control_a_r()
{
UINT8 ret;
// update CA1 & CA2 if callback exists, these in turn may update IRQ's
if (!m_in_ca1_func.isnull())
{
ca1_w(m_in_ca1_func());
}
else if(!m_logged_ca1_not_connected && (!m_in_ca1_pushed))
{
logerror("PIA #%s: Warning! No CA1 read handler. Assuming pin not connected\n", tag());
m_logged_ca1_not_connected = true;
}
if (!m_in_ca2_func.isnull())
{
ca2_w(m_in_ca2_func());
}
else if ( !m_logged_ca2_not_connected && C2_INPUT(m_ctl_a) && !m_in_ca2_pushed)
{
logerror("PIA #%s: Warning! No CA2 read handler. Assuming pin not connected\n", tag());
m_logged_ca2_not_connected = true;
}
// read control register
ret = m_ctl_a;
// set the IRQ flags if we have pending IRQs
if(m_irq_a1)
{
ret |= PIA_IRQ1;
}
if(m_irq_a2 && C2_INPUT(m_ctl_a))
{
ret |= PIA_IRQ2;
}
LOG(("PIA #%s: control A read = %02X\n", tag(), ret));
return ret;
}
static UINT8 control_b_r(const device_config *device)
{
pia6821_state *p = get_token(device);
UINT8 ret;
/* update CB1 & CB2 if callback exists, these in turn may update IRQ's */
if (p->in_cb1_func.read != NULL)
pia6821_cb1_w(device, 0, devcb_call_read_line(&p->in_cb1_func));
else if (!p->logged_cb1_not_connected && !p->in_cb1_pushed)
{
logerror("PIA #%s: Error! no CB1 read handler. Three-state pin is undefined\n", device->tag);
p->logged_cb1_not_connected = TRUE;
}
if (p->in_cb2_func.read != NULL)
pia6821_cb2_w(device, 0, devcb_call_read_line(&p->in_cb2_func));
else if (!p->logged_cb2_not_connected && C2_INPUT(p->ctl_b) && !p->in_cb2_pushed)
{
logerror("PIA #%s: Error! No CB2 read handler. Three-state pin is undefined\n", device->tag);
p->logged_cb2_not_connected = TRUE;
}
/* read control register */
ret = p->ctl_b;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_b1)
ret |= PIA_IRQ1;
if (p->irq_b2 && C2_INPUT(p->ctl_b))
ret |= PIA_IRQ2;
LOG(("PIA #%s: control B read = %02X\n", device->tag, ret));
return ret;
}
static UINT8 control_a_r(const device_config *device)
{
pia6821_state *p = get_token(device);
UINT8 ret;
/* update CA1 & CA2 if callback exists, these in turn may update IRQ's */
if (p->in_ca1_func.read != NULL)
pia6821_ca1_w(device, 0, devcb_call_read_line(&p->in_ca1_func));
else if (!p->logged_ca1_not_connected && (!p->in_ca1_pushed))
{
logerror("PIA #%s: Warning! No CA1 read handler. Assuming pin not connected\n", device->tag);
p->logged_ca1_not_connected = TRUE;
}
if (p->in_ca2_func.read != NULL)
pia6821_ca2_w(device, 0, devcb_call_read_line(&p->in_ca2_func));
else if ( !p->logged_ca2_not_connected && C2_INPUT(p->ctl_a) && !p->in_ca2_pushed)
{
logerror("PIA #%s: Warning! No CA2 read handler. Assuming pin not connected\n", device->tag);
p->logged_ca2_not_connected = TRUE;
}
/* read control register */
ret = p->ctl_a;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_a1)
ret |= PIA_IRQ1;
if (p->irq_a2 && C2_INPUT(p->ctl_a))
ret |= PIA_IRQ2;
LOG(("PIA #%s: control A read = %02X\n", device->tag, ret));
return ret;
}
int pia_read (int which, int offset)
{
struct pia6821 *p = pia + which;
int val = 0;
switch (pia_offsets[offset & 7])
{
/******************* port A output/DDR read *******************/
case 0:
/* read output register */
if (OUTPUT_SELECTED (p->ctl_a))
{
/* update the input */
if (p->in_a_func) p->in_a = p->in_a_func (0);
/* combine input and output values */
val = (p->out_a & p->ddr_a) + (p->in_a & ~p->ddr_a);
/* IRQ flags implicitly cleared by a read */
p->irq_a1 = p->irq_a2 = 0;
/* CA2 is configured as output and in read strobe mode */
if (C2_OUTPUT (p->ctl_a) && C2_STROBE_MODE (p->ctl_a))
{
/* this will cause a transition low; call the output function if we're currently high */
if (p->out_ca2)
if (p->out_ca2_func) p->out_ca2_func (0, 0);
p->out_ca2 = 0;
/* if the CA2 strobe is cleared by the E, reset it right away */
if (STROBE_E_RESET (p->ctl_a))
{
if (p->out_ca2_func) p->out_ca2_func (0, 1);
p->out_ca2 = 1;
}
}
}
/* read DDR register */
else
val = p->ddr_a;
break;
/******************* port B output/DDR read *******************/
case 1:
/* read output register */
if (OUTPUT_SELECTED (p->ctl_b))
{
/* update the input */
if (p->in_b_func) p->in_b = p->in_b_func (0);
/* combine input and output values */
val = (p->out_b & p->ddr_b) + (p->in_b & ~p->ddr_b);
/* IRQ flags implicitly cleared by a read */
p->irq_b1 = p->irq_b2 = 0;
}
/* read DDR register */
else
val = p->ddr_b;
break;
/******************* port A control read *******************/
case 2:
/* Update CA1 & CA2 if callback exists, these in turn may update IRQ's */
if (p->in_ca1_func) pia_set_input_ca1(which, p->in_ca1_func (0));
if (p->in_ca2_func) pia_set_input_ca2(which, p->in_ca2_func (0));
/* read control register */
val = p->ctl_a;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_a1) val |= PIA_IRQ1;
if (p->irq_a2 && C2_INPUT (p->ctl_a)) val |= PIA_IRQ2;
break;
/******************* port B control read *******************/
case 3:
/* Update CB1 & CB2 if callback exists, these in turn may update IRQ's */
if (p->in_cb1_func) pia_set_input_cb1(which, p->in_cb1_func (0));
if (p->in_cb2_func) pia_set_input_cb2(which, p->in_cb2_func (0));
/* read control register */
val = p->ctl_b;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_b1) val |= PIA_IRQ1;
if (p->irq_b2 && C2_INPUT (p->ctl_b)) val |= PIA_IRQ2;
break;
}
return val;
}
int pia_read(int which, int offset)
{
struct pia6821 *p = pia + which;
int val = 0;
/* adjust offset for 16-bit and ordering */
offset &= 3;
if (p->addr & PIA_ALTERNATE_ORDERING) offset = swizzle_address[offset];
switch (offset)
{
/******************* port A output/DDR read *******************/
case PIA_DDRA:
/* read output register */
if (OUTPUT_SELECTED(p->ctl_a))
{
/* update the input */
if ((FPTR)(p->intf->in_a_func) > 0x100)
p->in_a = p->intf->in_a_func(0);
#ifdef MAME_DEBUG
else if ((p->ddr_a ^ 0xff) && !(p->in_set & PIA_IN_SET_A)) {
logerror("PIA%d: Warning! no port A read handler. Assuming pins %02x not connected\n",
which, p->ddr_a ^ 0xff);
p->in_set |= PIA_IN_SET_A; // disable logging
}
#endif // MAME_DEBUG
/* combine input and output values */
val = (p->out_a & p->ddr_a) + (p->in_a & ~p->ddr_a);
/* IRQ flags implicitly cleared by a read */
p->irq_a1 = p->irq_a2 = 0;
update_6821_interrupts(p);
/* CA2 is configured as output and in read strobe mode */
if (C2_OUTPUT(p->ctl_a) && C2_STROBE_MODE(p->ctl_a))
{
/* this will cause a transition low; call the output function if we're currently high */
if (p->out_ca2)
if (p->intf->out_ca2_func) p->intf->out_ca2_func(0, 0);
p->out_ca2 = 0;
/* if the CA2 strobe is cleared by the E, reset it right away */
if (STROBE_E_RESET(p->ctl_a))
{
if (p->intf->out_ca2_func) p->intf->out_ca2_func(0, 1);
p->out_ca2 = 1;
}
}
LOG(("%04x: PIA%d read port A = %02X\n", activecpu_get_previouspc(), which, val));
}
/* read DDR register */
else
{
val = p->ddr_a;
LOG(("%04x: PIA%d read DDR A = %02X\n", activecpu_get_previouspc(), which, val));
}
break;
/******************* port B output/DDR read *******************/
case PIA_DDRB:
/* read output register */
if (OUTPUT_SELECTED(p->ctl_b))
{
/* update the input */
if ((FPTR)(p->intf->in_b_func) > 0x100)
p->in_b = p->intf->in_b_func(0);
#ifdef MAME_DEBUG
else if ((p->ddr_b ^ 0xff) && !(p->in_set & PIA_IN_SET_B)) {
logerror("PIA%d: Error! no port B read handler. Three-state pins %02x are undefined\n",
which, p->ddr_b ^ 0xff);
p->in_set |= PIA_IN_SET_B; // disable logging
}
#endif // MAME_DEBUG
/* combine input and output values */
val = (p->out_b & p->ddr_b) + (p->in_b & ~p->ddr_b);
/* IRQ flags implicitly cleared by a read */
p->irq_b1 = p->irq_b2 = 0;
update_6821_interrupts(p);
LOG(("%04x: PIA%d read port B = %02X\n", activecpu_get_previouspc(), which, val));
}
/* read DDR register */
else
{
val = p->ddr_b;
LOG(("%04x: PIA%d read DDR B = %02X\n", activecpu_get_previouspc(), which, val));
}
break;
/******************* port A control read *******************/
case PIA_CTLA:
/* Update CA1 & CA2 if callback exists, these in turn may update IRQ's */
if ((FPTR)(p->intf->in_ca1_func) > 0x100)
pia_set_input_ca1(which, p->intf->in_ca1_func(0));
#ifdef MAME_DEBUG
else if (!(p->in_set & PIA_IN_SET_CA1)) {
logerror("PIA%d: Warning! no CA1 read handler. Assuming pin not connected\n",which);
p->in_set |= PIA_IN_SET_CA1; // disable logging
}
#endif // MAME_DEBUG
if ((FPTR)(p->intf->in_ca2_func) > 0x100)
pia_set_input_ca2(which, p->intf->in_ca2_func(0));
#ifdef MAME_DEBUG
else if (C2_INPUT(p->ctl_a) && !(p->in_set & PIA_IN_SET_CA2)) {
logerror("PIA%d: Warning! no CA2 read handler. Assuming pin not connected\n",which);
p->in_set |= PIA_IN_SET_CA2; // disable logging
}
#endif // MAME_DEBUG
/* read control register */
val = p->ctl_a;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_a1) val |= PIA_IRQ1;
if (p->irq_a2 && C2_INPUT(p->ctl_a)) val |= PIA_IRQ2;
LOG(("%04x: PIA%d read control A = %02X\n", activecpu_get_previouspc(), which, val));
break;
/******************* port B control read *******************/
case PIA_CTLB:
/* Update CB1 & CB2 if callback exists, these in turn may update IRQ's */
if ((FPTR)(p->intf->in_cb1_func) > 0x100)
pia_set_input_cb1(which, p->intf->in_cb1_func(0));
#ifdef MAME_DEBUG
else if (!(p->in_set & PIA_IN_SET_CB1)) {
logerror("PIA%d: Error! no CB1 read handler. Three-state pin is undefined\n",which);
p->in_set |= PIA_IN_SET_CB1; // disable logging
}
#endif // MAME_DEBUG
if ((FPTR)(p->intf->in_cb2_func) > 0x100)
pia_set_input_cb2(which, p->intf->in_cb2_func(0));
#ifdef MAME_DEBUG
else if (C2_INPUT(p->ctl_b) && !(p->in_set & PIA_IN_SET_CB2)) {
logerror("PIA%d: Error! no CB2 read handler. Three-state pin is undefined\n",which);
p->in_set |= PIA_IN_SET_CB2; // disable logging
}
#endif // MAME_DEBUG
/* read control register */
val = p->ctl_b;
/* set the IRQ flags if we have pending IRQs */
if (p->irq_b1) val |= PIA_IRQ1;
if (p->irq_b2 && C2_INPUT(p->ctl_b)) val |= PIA_IRQ2;
LOG(("%04x: PIA%d read control B = %02X\n", activecpu_get_previouspc(), which, val));
break;
}
return val;
}
void pia_write(int which, int offset, int data)
{
pia6821 *p = pia + which;
/* adjust offset for 16-bit and ordering */
offset &= 3;
if (p->addr & PIA_ALTERNATE_ORDERING) offset = swizzle_address[offset];
switch (offset)
{
/******************* port A output/DDR write *******************/
case PIA_DDRA:
/* write output register */
if (OUTPUT_SELECTED(p->ctl_a))
{
LOG(("%04x: PIA%d port A write = %02X\n", activecpu_get_previouspc(), which, data));
/* update the output value */
p->out_a = data;/* & p->ddr_a; */ /* NS990130 - don't mask now, DDR could change later */
/* send it to the output function */
if (p->intf->out_a_func && p->ddr_a) p->intf->out_a_func(0, p->out_a & p->ddr_a); /* NS990130 */
}
/* write DDR register */
else
{
LOG(("%04x: PIA%d DDR A write = %02X\n", activecpu_get_previouspc(), which, data));
if (p->ddr_a != data)
{
/* NS990130 - if DDR changed, call the callback again */
p->ddr_a = data;
/* send it to the output function */
if (p->intf->out_a_func && p->ddr_a) p->intf->out_a_func(0, p->out_a & p->ddr_a);
}
}
break;
/******************* port B output/DDR write *******************/
case PIA_DDRB:
/* write output register */
if (OUTPUT_SELECTED(p->ctl_b))
{
LOG(("%04x: PIA%d port B write = %02X\n", activecpu_get_previouspc(), which, data));
/* update the output value */
p->out_b = data;/* & p->ddr_b */ /* NS990130 - don't mask now, DDR could change later */
/* send it to the output function */
if (p->intf->out_b_func && p->ddr_b) p->intf->out_b_func(0, p->out_b & p->ddr_b); /* NS990130 */
/* CB2 is configured as output and in write strobe mode */
if (C2_OUTPUT(p->ctl_b) && C2_STROBE_MODE(p->ctl_b))
{
/* this will cause a transition low; call the output function if we're currently high */
if (p->out_cb2)
if (p->intf->out_cb2_func) p->intf->out_cb2_func(0, 0);
p->out_cb2 = 0;
/* if the CB2 strobe is cleared by the E, reset it right away */
if (STROBE_E_RESET(p->ctl_b))
{
if (p->intf->out_cb2_func) p->intf->out_cb2_func(0, 1);
p->out_cb2 = 1;
}
}
}
/* write DDR register */
else
{
LOG(("%04x: PIA%d DDR B write = %02X\n", activecpu_get_previouspc(), which, data));
if (p->ddr_b != data)
{
/* NS990130 - if DDR changed, call the callback again */
p->ddr_b = data;
/* send it to the output function */
if (p->intf->out_b_func && p->ddr_b) p->intf->out_b_func(0, p->out_b & p->ddr_b);
}
}
break;
/******************* port A control write *******************/
case PIA_CTLA:
/* Bit 7 and 6 read only - PD 16/01/00 */
data &= 0x3f;
LOG(("%04x: PIA%d control A write = %02X\n", activecpu_get_previouspc(), which, data));
/* CA2 is configured as output */
if (C2_OUTPUT(data))
{
int temp;
if (C2_SET_MODE(data))
{
/* set/reset mode--bit value determines the new output */
temp = SET_C2(data) ? 1 : 0;
}
else {
/* strobe mode--output is always high unless strobed. */
temp = 1;
}
/* if we're going from input to output mode, or we're already in output mode
and this change creates a transition, call the CA2 output function */
if (C2_INPUT(p->ctl_a) || (C2_OUTPUT(p->ctl_a) && (p->out_ca2 ^ temp)))
if (p->intf->out_ca2_func) p->intf->out_ca2_func(0, temp);
/* set the new value */
p->out_ca2 = temp;
}
/* update the control register */
p->ctl_a = data;
/* update externals */
update_6821_interrupts(p);
break;
/******************* port B control write *******************/
case PIA_CTLB:
/* Bit 7 and 6 read only - PD 16/01/00 */
data &= 0x3f;
LOG(("%04x: PIA%d control B write = %02X\n", activecpu_get_previouspc(), which, data));
/* CB2 is configured as output */
if (C2_OUTPUT(data))
{
int temp;
if (C2_SET_MODE(data))
{
/* set/reset mode--bit value determines the new output */
temp = SET_C2(data) ? 1 : 0;
}
else {
/* strobe mode--output is always high unless strobed. */
temp = 1;
}
/* if we're going from input to output mode, or we're already in output mode
and this change creates a transition, call the CB2 output function */
if (C2_INPUT(p->ctl_b) || (C2_OUTPUT(p->ctl_b) && (p->out_cb2 ^ temp)))
if (p->intf->out_cb2_func) p->intf->out_cb2_func(0, temp);
/* set the new value */
p->out_cb2 = temp;
}
/* update the control register */
p->ctl_b = data;
/* update externals */
update_6821_interrupts(p);
break;
}
}
