// license:BSD-3-Clause
// copyright-holders:Ramiro Polla
/*
* E05A30 Gate Array (used in the Epson ActionPrinter 2000)
*
*/
#include "emu.h"
#include "e05a30.h"
//#define E05A30DEBUG
#ifdef E05A30DEBUG
#define LOG(...) fprintf(stderr, __VA_ARGS__)
#else
#define LOG(...)
#endif
/*****************************************************************************
DEVICE INTERFACE
*****************************************************************************/
const device_type E05A30 = device_creator<e05a30_device>;
e05a30_device::e05a30_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, E05A30, "E05A30", tag, owner, clock, "e05a30", __FILE__),
m_write_printhead(*this),
m_write_pf_stepper(*this),
m_write_cr_stepper(*this),
m_write_ready(*this),
m_write_centronics_ack(*this),
m_write_centronics_busy(*this),
m_write_centronics_perror(*this),
m_write_centronics_fault(*this),
m_write_centronics_select(*this),
m_printhead(0),
m_pf_stepper(0),
m_cr_stepper(0), m_centronics_data(0), m_centronics_busy(0), m_centronics_nack(0), m_centronics_strobe(0), m_centronics_data_latch(0), m_centronics_data_latched(0)
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void e05a30_device::device_start()
{
/* resolve callbacks */
m_write_printhead.resolve_safe();
m_write_pf_stepper.resolve_safe();
m_write_cr_stepper.resolve_safe();
m_write_ready.resolve_safe();
m_write_centronics_ack.resolve_safe();
m_write_centronics_busy.resolve_safe();
m_write_centronics_perror.resolve_safe();
m_write_centronics_fault.resolve_safe();
m_write_centronics_select.resolve_safe();
/* register for state saving */
save_item(NAME(m_printhead));
save_item(NAME(m_pf_stepper));
save_item(NAME(m_cr_stepper));
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void e05a30_device::device_reset()
{
m_printhead = 0x00;
m_pf_stepper = 0x00;
m_cr_stepper = 0x00;
/* centronics init */
m_centronics_nack = false;
m_centronics_busy = false;
m_write_centronics_ack (!m_centronics_nack);
m_write_centronics_busy ( m_centronics_busy);
m_write_centronics_perror(false);
m_write_centronics_fault (true);
m_write_centronics_select(true);
m_write_ready(1);
}
/***************************************************************************
PRINT HEAD
***************************************************************************/
/* The e05a30 controls the printhead through MMIOs 0xC005 and 0xC006.
* MMIO 0xC006 keeps the first 8 pins.
* MMIO 0xC005 keeps the 9th pin in the MSB.
*/
void e05a30_device::update_printhead(int pos, uint8_t data)
{
if (pos == 0) {
m_printhead &= 0x01fe;
m_printhead |= (data >> 7);
} else {
m_printhead &= 0x0001;
m_printhead |= (uint16_t) (data << 1);
}
m_write_printhead(m_printhead);
}
/***************************************************************************
STEPPER MOTORS
***************************************************************************/
/* The e05a30 controls two stepper motors:
* - The Paper Feed stepper motor is controlled through MMIO 0xC007
* - The Carriage Return stepper motor is controlled through MMIO 0xC008
* The Carriage Return stepper motor is used throug the SLA7020M driver. It
* is therefore necessary to translate the input data from the SLA7020M
* format to a format describing the 4 phases of a stepper motor.
* For the PF motor, the output data is fed directly to the stepper motor.
*/
void e05a30_device::update_pf_stepper(uint8_t data)
{
m_pf_stepper = data & 0x0f;
m_write_pf_stepper(m_pf_stepper);
}
static uint8_t cr_sla7020m(uint8_t data)
{
bool ina = BIT(data, 0);
bool inb = BIT(data, 1);
bool tda = BIT(data, 2);
bool tdb = BIT(data, 3);
bool outa0 = ina && tda;
bool outa1 = !ina && tda;
bool outb0 = inb && tdb;
bool outb1 = !inb && tdb;
return (outb1<<3)|(outb0<<2)|(outa1<<1)|(outa0<<0);
}
void e05a30_device::update_cr_stepper(uint8_t data)
{
m_cr_stepper = data & 0x0f;
m_write_cr_stepper(cr_sla7020m(m_cr_stepper));
}
/***************************************************************************
Centronics
***************************************************************************/
WRITE_LINE_MEMBER( e05a30_device::centronics_input_strobe )
{
if (m_centronics_strobe == true && state == false && !m_centronics_busy) {
m_centronics_data_latch = m_centronics_data;
m_centronics_data_latched = true;
m_centronics_busy = true;
m_write_centronics_busy(m_centronics_busy);
}
m_centronics_strobe = state;
}
/***************************************************************************
IMPLEMENTATION
***************************************************************************/
WRITE8_MEMBER( e05a30_device::write )
{
LOG("%s: e05a30_w([0xC0%02x]): %02x\n", space.machine().describe_context(), offset, data);
switch (offset) {
case 0x04:
m_centronics_nack = BIT(data,5);
m_centronics_busy = BIT(data,0);
/* The ActionPrinter 2000 firmware might overwrite the busy signal at
* address 20AB if the host depends only on the busy signal and
* doesn't wait for the ack pulse. To avoid skipping input data, we
* assume the busy signal cannot be reset while the data hasn't been
* read. */
if (m_centronics_data_latched)
m_centronics_busy = true;
m_write_centronics_ack (!m_centronics_nack);
m_write_centronics_busy( m_centronics_busy);
break;
/* printhead */
case 0x05: update_printhead(0, data); break;
case 0x06: update_printhead(1, data); break;
/* paper feed stepper motor */
case 0x07: update_pf_stepper(data); break;
/* carriage return stepper motor */
case 0x08: update_cr_stepper(data); break;
}
}
READ8_MEMBER( e05a30_device::read )
{
uint8_t result = 0;
LOG("%s: e05a30_r([0xC0%02x]): ", space.machine().describe_context(), offset);
switch (offset) {
case 0x02:
result = m_centronics_data_latched << 7;
break;
case 0x03:
result = m_centronics_data_latch;
m_centronics_data_latched = false;
break;
case 0x04:
result |= m_centronics_busy << 0;
result |= m_centronics_nack << 5;
break;
/* paper feed stepper motor */
case 0x07: result = m_pf_stepper; break;
/* carriage return stepper motor */
case 0x08: result = m_cr_stepper; break;
}
LOG("0x%02x\n", result);
return result;
}