// license:BSD-3-Clause
// copyright-holders:AJR
/**********************************************************************
SWTPC MP-C Serial Control Interface
**********************************************************************/
#include "emu.h"
#include "mpc.h"
#include "bus/rs232/rs232.h"
#include "machine/6821pia.h"
#include "machine/input_merger.h"
#include "machine/ripple_counter.h"
//**************************************************************************
// TYPE DEFINITIONS
//**************************************************************************
// ======================> ss50_mpc_device
class ss50_mpc_device : public device_t, public ss50_card_interface
{
public:
// construction/destruction
ss50_mpc_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
: device_t(mconfig, SS50_MPC, tag, owner, clock),
ss50_card_interface(mconfig, *this),
m_pia(*this, "pia"),
m_loopback(*this, "loopback"),
m_counter(*this, "counter"),
m_baud_jumper(*this, "BAUD"),
m_count_select(false)
{
}
protected:
// device-specific overrides
virtual ioport_constructor device_input_ports() const override;
virtual void device_add_mconfig(machine_config &config) override;
virtual void device_start() override;
// interface-specific overrides
virtual DECLARE_READ8_MEMBER(register_read) override;
virtual DECLARE_WRITE8_MEMBER(register_write) override;
virtual DECLARE_WRITE_LINE_MEMBER(f110_w) override;
virtual DECLARE_WRITE_LINE_MEMBER(f300_w) override;
private:
DECLARE_WRITE_LINE_MEMBER(serial_input_w);
DECLARE_WRITE_LINE_MEMBER(reader_control_w);
DECLARE_READ_LINE_MEMBER(count_r);
DECLARE_WRITE_LINE_MEMBER(count_select_w);
required_device<pia6821_device> m_pia;
required_device<input_merger_device> m_loopback;
required_device<ripple_counter_device> m_counter;
required_ioport m_baud_jumper;
bool m_count_select;
};
static INPUT_PORTS_START( mpc )
PORT_START("BAUD")
PORT_DIPNAME(1, 0, "Baud Rate")
PORT_DIPSETTING(1, "110")
PORT_DIPSETTING(0, "300")
PORT_START("STOP")
PORT_DIPNAME(1, 0, "Stop Bits")
PORT_DIPSETTING(0, "1")
PORT_DIPSETTING(1, "2")
INPUT_PORTS_END
//-------------------------------------------------
// input_ports - device-specific input ports
//-------------------------------------------------
ioport_constructor ss50_mpc_device::device_input_ports() const
{
return INPUT_PORTS_NAME(mpc);
}
static DEVICE_INPUT_DEFAULTS_START( terminal )
DEVICE_INPUT_DEFAULTS("RS232_RXBAUD", 0xff, RS232_BAUD_300)
DEVICE_INPUT_DEFAULTS("RS232_TXBAUD", 0xff, RS232_BAUD_300)
DEVICE_INPUT_DEFAULTS("RS232_STARTBITS", 0xff, RS232_STARTBITS_1)
DEVICE_INPUT_DEFAULTS("RS232_DATABITS", 0xff, RS232_DATABITS_8)
DEVICE_INPUT_DEFAULTS("RS232_PARITY", 0xff, RS232_PARITY_NONE)
DEVICE_INPUT_DEFAULTS("RS232_STOPBITS", 0xff, RS232_STOPBITS_1)
DEVICE_INPUT_DEFAULTS_END
//-------------------------------------------------
// device_add_mconfig - add device-specific
// machine configuration
//-------------------------------------------------
MACHINE_CONFIG_START(ss50_mpc_device::device_add_mconfig)
MCFG_DEVICE_ADD("pia", PIA6821, 0) // actually MC6820
MCFG_PIA_WRITEPA_HANDLER(WRITELINE("outgate", input_merger_device, in_w<0>)) MCFG_DEVCB_BIT(0)
MCFG_PIA_CB2_HANDLER(WRITELINE(*this, ss50_mpc_device, reader_control_w))
MCFG_PIA_READPB_HANDLER(IOPORT("STOP")) MCFG_DEVCB_BIT(6)
MCFG_DEVCB_CHAIN_INPUT(READLINE(*this, ss50_mpc_device, count_r)) MCFG_DEVCB_BIT(7)
MCFG_PIA_WRITEPB_HANDLER(WRITELINE(*this, ss50_mpc_device, count_select_w)) MCFG_DEVCB_BIT(2)
MCFG_DEVCB_CHAIN_OUTPUT(WRITELINE("counter", ripple_counter_device, reset_w)) MCFG_DEVCB_BIT(0)
//MCFG_PIA_IRQA_HANDLER(WRITELINE(*this, ss50_mpc_device, pia_irq_w))
//MCFG_PIA_IRQB_HANDLER(WRITELINE(*this, ss50_mpc_device, pia_irq_w))
MCFG_DEVICE_ADD("rs232", RS232_PORT, default_rs232_devices, "terminal")
MCFG_RS232_RXD_HANDLER(WRITELINE(*this, ss50_mpc_device, serial_input_w))
MCFG_SLOT_OPTION_DEVICE_INPUT_DEFAULTS("terminal", terminal)
MCFG_INPUT_MERGER_ALL_HIGH("outgate")
MCFG_INPUT_MERGER_OUTPUT_HANDLER(WRITELINE("rs232", rs232_port_device, write_txd))
MCFG_INPUT_MERGER_ANY_HIGH("loopback")
MCFG_INPUT_MERGER_OUTPUT_HANDLER(WRITELINE("outgate", input_merger_device, in_w<1>))
MCFG_DEVICE_ADD("counter", RIPPLE_COUNTER, 0) // CD4024AE (IC3)
MCFG_RIPPLE_COUNTER_STAGES(7) // only Q5 (÷32) and Q4 (÷16) are actually used
MACHINE_CONFIG_END
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void ss50_mpc_device::device_start()
{
save_item(NAME(m_count_select));
}
WRITE_LINE_MEMBER(ss50_mpc_device::serial_input_w)
{
m_pia->set_a_input(state << 7, 0x7f);
m_loopback->in_w<0>(state);
}
WRITE_LINE_MEMBER(ss50_mpc_device::reader_control_w)
{
m_loopback->in_w<1>(state);
}
READ_LINE_MEMBER(ss50_mpc_device::count_r)
{
return BIT(m_counter->count(), m_count_select ? 4 : 3);
}
WRITE_LINE_MEMBER(ss50_mpc_device::count_select_w)
{
m_count_select = bool(state);
}
//-------------------------------------------------
// register_read - read from a port register
//-------------------------------------------------
READ8_MEMBER(ss50_mpc_device::register_read)
{
return m_pia->read(space, offset & 3, 0);
}
//-------------------------------------------------
// register_write - write to a port register
//-------------------------------------------------
WRITE8_MEMBER(ss50_mpc_device::register_write)
{
m_pia->write(space, offset & 3, data);
}
WRITE_LINE_MEMBER(ss50_mpc_device::f110_w)
{
if (m_baud_jumper->read())
m_counter->clock_w(state);
}
WRITE_LINE_MEMBER(ss50_mpc_device::f300_w)
{
if (!m_baud_jumper->read())
m_counter->clock_w(state);
}
// device type definition
DEFINE_DEVICE_TYPE_PRIVATE(SS50_MPC, ss50_card_interface, ss50_mpc_device, "ss50_mpc", "MP-C Serial Control Interface")