// license:BSD-3-Clause
// copyright-holders:Nathan Woods
/**********************************************************************
Motorola 6821 PIA interface and emulation
Notes:
* get_port_b_z_mask() gives the caller the bitmask that shows
which bits are high-impendance when reading port B, and thus
neither 0 or 1. get_output_cb2_z() returns the same info
for the CB2 pin.
* set_port_a_z_mask allows the input callback to indicate
which port A bits are disconnected. For these bits, the
read operation will return the output buffer's contents.
* The 'alt' interface functions are used when the A0 and A1
address bits are swapped.
* All 'int' data or return values are bool, and should be
converted to bool at some point.
**********************************************************************/
#pragma once
#ifndef __6821PIA_H__
#define __6821PIA_H__
#include "emu.h"
/***************************************************************************
DEVICE CONFIGURATION MACROS
***************************************************************************/
// TODO: REMOVE THESE
#define MCFG_PIA_READPA_HANDLER(_devcb) \
devcb = &pia6821_device::set_readpa_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_READPB_HANDLER(_devcb) \
devcb = &pia6821_device::set_readpb_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_READCA1_HANDLER(_devcb) \
devcb = &pia6821_device::set_readca1_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_READCA2_HANDLER(_devcb) \
devcb = &pia6821_device::set_readca2_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_READCB1_HANDLER(_devcb) \
devcb = &pia6821_device::set_readcb1_handler(*device, DEVCB_##_devcb);
// TODO: CONVERT THESE TO WRITE LINE
#define MCFG_PIA_WRITEPA_HANDLER(_devcb) \
devcb = &pia6821_device::set_writepa_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_WRITEPB_HANDLER(_devcb) \
devcb = &pia6821_device::set_writepb_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_CA2_HANDLER(_devcb) \
devcb = &pia6821_device::set_ca2_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_CB2_HANDLER(_devcb) \
devcb = &pia6821_device::set_cb2_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_IRQA_HANDLER(_devcb) \
devcb = &pia6821_device::set_irqa_handler(*device, DEVCB_##_devcb);
#define MCFG_PIA_IRQB_HANDLER(_devcb) \
devcb = &pia6821_device::set_irqb_handler(*device, DEVCB_##_devcb);
/***************************************************************************
TYPE DEFINITIONS
***************************************************************************/
// ======================> pia6821_device
class pia6821_device : public device_t
{
public:
// construction/destruction
pia6821_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
// static configuration helpers
// TODO: REMOVE THESE
template<class _Object> static devcb_base &set_readpa_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_in_a_handler.set_callback(object); }
template<class _Object> static devcb_base &set_readpb_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_in_b_handler.set_callback(object); }
template<class _Object> static devcb_base &set_readca1_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_in_ca1_handler.set_callback(object); }
template<class _Object> static devcb_base &set_readca2_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_in_ca2_handler.set_callback(object); }
template<class _Object> static devcb_base &set_readcb1_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_in_cb1_handler.set_callback(object); }
// TODO: CONVERT THESE TO WRITE LINE
template<class _Object> static devcb_base &set_writepa_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_out_a_handler.set_callback(object); }
template<class _Object> static devcb_base &set_writepb_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_out_b_handler.set_callback(object); }
template<class _Object> static devcb_base &set_ca2_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_ca2_handler.set_callback(object); }
template<class _Object> static devcb_base &set_cb2_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_cb2_handler.set_callback(object); }
template<class _Object> static devcb_base &set_irqa_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_irqa_handler.set_callback(object); }
template<class _Object> static devcb_base &set_irqb_handler(device_t &device, _Object object) { return downcast<pia6821_device &>(device).m_irqb_handler.set_callback(object); }
DECLARE_READ8_MEMBER( read ) { return reg_r(offset); }
DECLARE_WRITE8_MEMBER( write ) { reg_w(offset, data); }
DECLARE_READ8_MEMBER( read_alt ) { return reg_r(((offset << 1) & 0x02) | ((offset >> 1) & 0x01)); }
DECLARE_WRITE8_MEMBER( write_alt ) { reg_w(((offset << 1) & 0x02) | ((offset >> 1) & 0x01), data); }
UINT8 port_b_z_mask() const { return ~m_ddr_b; } // see first note in .c
void set_port_a_z_mask(UINT8 data) { m_port_a_z_mask = data; }// see second note in .c
DECLARE_WRITE8_MEMBER( porta_w ) { porta_w(data); }
void porta_w(UINT8 data);
void set_a_input(UINT8 data, UINT8 z_mask);
UINT8 a_output();
DECLARE_WRITE_LINE_MEMBER( ca1_w );
DECLARE_WRITE_LINE_MEMBER( ca2_w );
int ca2_output();
int ca2_output_z();
DECLARE_WRITE8_MEMBER( portb_w ) { portb_w(data); }
void portb_w(UINT8 data);
UINT8 b_output();
DECLARE_WRITE_LINE_MEMBER( cb1_w );
DECLARE_WRITE_LINE_MEMBER( cb2_w );
int cb2_output();
int cb2_output_z();
int irq_a_state() const { return m_irq_a_state; }
int irq_b_state() const { return m_irq_b_state; }
protected:
// device-level overrides
virtual void device_start() override;
virtual void device_reset() override;
private:
UINT8 reg_r(UINT8 offset);
void reg_w(UINT8 offset, UINT8 data);
void update_interrupts();
UINT8 get_in_a_value();
UINT8 get_in_b_value();
UINT8 get_out_a_value();
UINT8 get_out_b_value();
void set_out_ca2(int data);
void set_out_cb2(int data);
UINT8 port_a_r();
UINT8 ddr_a_r();
UINT8 control_a_r();
UINT8 port_b_r();
UINT8 ddr_b_r();
UINT8 control_b_r();
void send_to_out_a_func(const char* message);
void send_to_out_b_func(const char* message);
void port_a_w(UINT8 data);
void ddr_a_w(UINT8 data);
void port_b_w(UINT8 data);
void ddr_b_w(UINT8 data);
void control_a_w(UINT8 data);
void control_b_w(UINT8 data);
devcb_read8 m_in_a_handler;
devcb_read8 m_in_b_handler;
devcb_read_line m_in_ca1_handler;
devcb_read_line m_in_cb1_handler;
devcb_read_line m_in_ca2_handler;
devcb_write8 m_out_a_handler;
devcb_write8 m_out_b_handler;
devcb_write_line m_ca2_handler;
devcb_write_line m_cb2_handler;
devcb_write_line m_irqa_handler;
devcb_write_line m_irqb_handler;
UINT8 m_in_a;
UINT8 m_in_ca1;
UINT8 m_in_ca2;
UINT8 m_out_a;
UINT8 m_out_ca2;
UINT8 m_port_a_z_mask;
UINT8 m_ddr_a;
UINT8 m_ctl_a;
UINT8 m_irq_a1;
UINT8 m_irq_a2;
UINT8 m_irq_a_state;
UINT8 m_in_b;
UINT8 m_in_cb1;
UINT8 m_in_cb2;
UINT8 m_out_b;
UINT8 m_out_cb2;
UINT8 m_last_out_cb2_z;
UINT8 m_ddr_b;
UINT8 m_ctl_b;
UINT8 m_irq_b1;
UINT8 m_irq_b2;
UINT8 m_irq_b_state;
// variables that indicate if access a line externally -
// used to for logging purposes ONLY
bool m_in_a_pushed;
bool m_out_a_needs_pulled;
bool m_in_ca1_pushed;
bool m_in_ca2_pushed;
bool m_out_ca2_needs_pulled;
bool m_in_b_pushed;
bool m_out_b_needs_pulled;
bool m_in_cb1_pushed;
bool m_in_cb2_pushed;
bool m_out_cb2_needs_pulled;
bool m_logged_port_a_not_connected;
bool m_logged_port_b_not_connected;
bool m_logged_ca1_not_connected;
bool m_logged_ca2_not_connected;
bool m_logged_cb1_not_connected;
bool m_logged_cb2_not_connected;
};
// device type definition
extern const device_type PIA6821;
#endif /* __6821PIA_H__ */