void i8251_device::device_reset()
{
LOG(("I8251: Reset\n"));
/* what is the default setup when the 8251 has been reset??? */
/* i8251 datasheet explains the state of tx pin at reset */
/* tx is set to 1 */
set_out_data_bit(1);
/* assumption, rts is set to 1 */
m_connection_state &= ~SERIAL_STATE_RTS;
serial_connection_out();
transmit_register_reset();
receive_register_reset();
/* expecting mode byte */
m_flags |= I8251_EXPECTING_MODE;
/* not expecting a sync byte */
m_flags &= ~I8251_EXPECTING_SYNC_BYTE;
/* no character to read by cpu */
/* transmitter is ready and is empty */
m_status = I8251_STATUS_TX_EMPTY | I8251_STATUS_TX_READY;
m_mode_byte = 0;
m_command = 0;
/* update tx empty pin output */
update_tx_empty();
/* update rx ready pin output */
update_rx_ready();
/* update tx ready pin output */
update_tx_ready();
}
void wangpc_keyboard_device::device_reset()
{
transmit_register_reset();
receive_register_reset();
set_out_data_bit(1);
serial_connection_out();
}
static TIMER_CALLBACK(poly88_cassette_timer_callback)
{
poly88_state *state = machine.driver_data<poly88_state>();
int data;
int current_level;
// if (!(input_port_read(machine, "DSW0") & 0x02)) /* V.24 / Tape Switch */
//{
/* tape reading */
if (cassette_get_state(machine.device("cassette"))&CASSETTE_PLAY)
{
if (state->m_clk_level_tape)
{
state->m_previous_level = (cassette_input(machine.device("cassette")) > 0.038) ? 1 : 0;
state->m_clk_level_tape = 0;
}
else
{
current_level = (cassette_input(machine.device("cassette")) > 0.038) ? 1 : 0;
if (state->m_previous_level!=current_level)
{
data = (!state->m_previous_level && current_level) ? 1 : 0;
//data = current_level;
set_out_data_bit(state->m_cassette_serial_connection.State, data);
serial_connection_out(machine, &state->m_cassette_serial_connection);
msm8251_receive_clock(machine.device("uart"));
state->m_clk_level_tape = 1;
}
}
}
/* tape writing */
if (cassette_get_state(machine.device("cassette"))&CASSETTE_RECORD)
{
data = get_in_data_bit(state->m_cassette_serial_connection.input_state);
data ^= state->m_clk_level_tape;
cassette_output(machine.device("cassette"), data&0x01 ? 1 : -1);
if (!state->m_clk_level_tape)
msm8251_transmit_clock(machine.device("uart"));
state->m_clk_level_tape = state->m_clk_level_tape ? 0 : 1;
return;
}
state->m_clk_level_tape = 1;
if (!state->m_clk_level)
msm8251_transmit_clock(machine.device("uart"));
state->m_clk_level = state->m_clk_level ? 0 : 1;
// }
}
void i8251_device::update_tx_empty()
{
if (m_status & I8251_STATUS_TX_EMPTY)
{
/* tx is in marking state (high) when tx empty! */
set_out_data_bit(1);
serial_connection_out();
}
m_out_txempty_func((m_status & I8251_STATUS_TX_EMPTY) != 0);
}
void z80dart_channel::tra_complete()
{
if ((m_wr[5] & WR5_TX_ENABLE) && !(m_wr[5] & WR5_SEND_BREAK) && !(m_rr[0] & RR0_TX_BUFFER_EMPTY))
{
LOG(("Z80DART \"%s\" Channel %c : Transmit Data Byte '%02x'\n", m_owner->tag(), 'A' + m_index, m_tx_data));
transmit_register_setup(m_tx_data);
// empty transmit buffer
m_rr[0] |= RR0_TX_BUFFER_EMPTY;
if (m_wr[1] & WR1_TX_INT_ENABLE)
m_uart->trigger_interrupt(m_index, INT_TRANSMIT);
}
else if (m_wr[5] & WR5_SEND_BREAK)
{
// transmit break
m_out_txd_func(0);
set_out_data_bit(0);
}
else
{
// transmit mark
m_out_txd_func(1);
set_out_data_bit(1);
}
// if transmit buffer is empty
if (m_rr[0] & RR0_TX_BUFFER_EMPTY)
{
// then all characters have been sent
m_rr[1] |= RR1_ALL_SENT;
// when the RTS bit is reset, the _RTS output goes high after the transmitter empties
if (!m_rts)
set_rts(1);
}
}
void z80dart_channel::tra_callback()
{
if (!(m_wr[5] & WR5_TX_ENABLE))
{
// transmit mark
m_out_txd_func(1);
set_out_data_bit(1);
}
else if (m_wr[5] & WR5_SEND_BREAK)
{
// transmit break
m_out_txd_func(0);
set_out_data_bit(0);
}
else if (!is_transmit_register_empty())
{
// transmit data
if (m_out_txd_func.isnull())
transmit_register_send_bit();
else
m_out_txd_func(transmit_register_get_data_bit());
}
}
/* only works for one cassette so far */
static void exidy_cassette_timer_callback(int dummy)
{
cassette_clock_counter++;
if (cassette_clock_counter==(4800/1200))
{
/* reset counter */
cassette_clock_counter = 0;
/* toggle state of clock */
cassette_clock_state^=0x0ffffffff;
/* previously was 0, now gone 1 */
/* +ve edge detected */
if (cassette_clock_state)
{
int bit;
/* clock bits into cassette flip flops */
/* bit is inverted! */
/* detect level */
bit = 1;
if (cassette_input(image_from_devtype_and_index(IO_CASSETTE, 0)) > 0.0038)
bit = 0;
cassette_input_ff[0] = bit;
/* detect level */
bit = 1;
if (cassette_input(image_from_devtype_and_index(IO_CASSETTE, 1)) > 0.0038)
bit = 0;
cassette_input_ff[1] = bit;
logerror("cassette bit: %0d\n",bit);
/* set out data bit */
set_out_data_bit(cassette_serial_connection.State, cassette_input_ff[0]);
/* output through serial connection */
serial_connection_out(&cassette_serial_connection);
/* update hd6402 receive clock */
hd6402_receive_clock();
}
}
}
