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Diffstat (limited to 'src/devices/machine/ins8250.cpp')
-rw-r--r--src/devices/machine/ins8250.cpp123
1 files changed, 75 insertions, 48 deletions
diff --git a/src/devices/machine/ins8250.cpp b/src/devices/machine/ins8250.cpp
index d586816c511..cfbe099beed 100644
--- a/src/devices/machine/ins8250.cpp
+++ b/src/devices/machine/ins8250.cpp
@@ -81,7 +81,7 @@ ASCII/EBCDIC control character recognition, timed interrupts and more.
Known issues:
-- MESS does currently not handle all these model specific features.
+- MAME does currently not handle all these model specific features.
History:
@@ -95,7 +95,7 @@ History:
**********************************************************************/
#include "emu.h"
-#include "machine/ins8250.h"
+#include "ins8250.h"
#include <algorithm>
@@ -111,6 +111,7 @@ ins8250_uart_device::ins8250_uart_device(const machine_config &mconfig, device_t
: device_t(mconfig, type, tag, owner, clock)
, device_serial_interface(mconfig, *this)
, m_device_type(device_type)
+ , m_regs{0}
, m_out_tx_cb(*this)
, m_out_dtr_cb(*this)
, m_out_rts_cb(*this)
@@ -178,7 +179,7 @@ static constexpr u8 INS8250_LCR_2STOP_BITS = 0x04;
//static constexpr u8 INS8250_LCR_PEN = 0x08;
//static constexpr u8 INS8250_LCR_EVEN_PAR = 0x10;
//static constexpr u8 INS8250_LCR_PARITY = 0x20;
-//static constexpr u8 INS8250_LCR_BREAK = 0x40;
+static constexpr u8 INS8250_LCR_BREAK = 0x40;
static constexpr u8 INS8250_LCR_DLAB = 0x80;
/* ints will continue to be set for as long as there are ints pending */
@@ -240,7 +241,7 @@ void ins8250_uart_device::clear_int(int flag)
update_interrupt();
}
-READ_LINE_MEMBER(ins8250_uart_device::intrpt_r)
+int ins8250_uart_device::intrpt_r()
{
return !BIT(m_regs.iir, 0);
}
@@ -298,9 +299,11 @@ void ins8250_uart_device::ins8250_w(offs_t offset, u8 data)
set_fcr(data);
break;
case 3:
+ {
+ bool break_state_changed = bool((m_regs.lcr ^ data) & INS8250_LCR_BREAK);
+
m_regs.lcr = data;
- {
int data_bit_count = (m_regs.lcr & INS8250_LCR_BITCOUNT_MASK) + 5;
parity_t parity;
stop_bits_t stop_bits;
@@ -335,6 +338,19 @@ void ins8250_uart_device::ins8250_w(offs_t offset, u8 data)
else
stop_bits = STOP_BITS_2;
+ if (break_state_changed)
+ {
+ int new_out_val = (m_regs.lcr & INS8250_LCR_BREAK) ? 0 : m_txd;
+
+ if (m_regs.mcr & INS8250_MCR_LOOPBACK)
+ {
+ device_serial_interface::rx_w(new_out_val);
+ }
+ else
+ {
+ m_out_tx_cb(new_out_val);
+ }
+ }
set_data_frame(1, data_bit_count, parity, stop_bits);
}
break;
@@ -348,7 +364,10 @@ void ins8250_uart_device::ins8250_w(offs_t offset, u8 data)
if (m_regs.mcr & INS8250_MCR_LOOPBACK)
{
m_out_tx_cb(1);
- device_serial_interface::rx_w(m_txd);
+ if ((m_regs.lcr & INS8250_LCR_BREAK) == 0)
+ {
+ device_serial_interface::rx_w(m_txd);
+ }
m_out_dtr_cb(1);
m_out_rts_cb(1);
m_out_out1_cb(1);
@@ -356,7 +375,10 @@ void ins8250_uart_device::ins8250_w(offs_t offset, u8 data)
}
else
{
- m_out_tx_cb(m_txd);
+ if ((m_regs.lcr & INS8250_LCR_BREAK) == 0)
+ {
+ m_out_tx_cb(m_txd);
+ }
device_serial_interface::rx_w(m_rxd);
m_out_dtr_cb((m_regs.mcr & INS8250_MCR_DTR) ? 0 : 1);
m_out_rts_cb((m_regs.mcr & INS8250_MCR_RTS) ? 0 : 1);
@@ -385,16 +407,20 @@ void ins8250_uart_device::ins8250_w(offs_t offset, u8 data)
This register can be written, but if you write a 1 bit into any of
bits 3 - 0, you could cause an interrupt if the appropriate IER bit
is set.
+ Bits 7 - 4 are read-only.
*/
- m_regs.msr = data;
+ m_regs.msr = (m_regs.msr & 0xf0) | (data & 0x0f);
- if ( m_regs.msr & 0x0f )
+ if (m_regs.msr & 0x0f)
trigger_int(COM_INT_PENDING_MODEM_STATUS_REGISTER);
else
clear_int(COM_INT_PENDING_MODEM_STATUS_REGISTER);
break;
case 7:
- m_regs.scr = data;
+ if (m_device_type >= dev_type::INS8250A)
+ {
+ m_regs.scr = data;
+ }
break;
}
}
@@ -434,8 +460,11 @@ u8 ins8250_uart_device::ins8250_r(offs_t offset)
data = m_regs.iir;
/* The documentation says that reading this register will
clear the int if this is the source of the int */
- if (!machine().side_effects_disabled() && (m_regs.ier & COM_INT_PENDING_TRANSMITTER_HOLDING_REGISTER_EMPTY))
- clear_int(COM_INT_PENDING_TRANSMITTER_HOLDING_REGISTER_EMPTY);
+ if (!machine().side_effects_disabled())
+ {
+ if ((m_regs.iir & 0x0f) == 0x02)
+ clear_int(COM_INT_PENDING_TRANSMITTER_HOLDING_REGISTER_EMPTY);
+ }
break;
case 3:
data = m_regs.lcr;
@@ -464,7 +493,10 @@ u8 ins8250_uart_device::ins8250_r(offs_t offset)
}
break;
case 7:
- data = m_regs.scr;
+ if (m_device_type >= dev_type::INS8250A)
+ {
+ data = m_regs.scr;
+ }
break;
}
return data;
@@ -527,27 +559,24 @@ void ns16550_device::tra_complete()
void ins8250_uart_device::rcv_complete()
{
+ // According to datasheet (and HP82939 self-test) the received character is always
+ // extracted and stored in RBR even in case of overrun
+ receive_register_extract();
if(m_regs.lsr & INS8250_LSR_DR)
{
m_regs.lsr |= INS8250_LSR_OE; //overrun
- trigger_int(COM_INT_PENDING_RECEIVER_LINE_STATUS);
- receive_register_reset();
}
- else
- {
- m_regs.lsr |= INS8250_LSR_DR;
- receive_register_extract();
-
- if (is_receive_framing_error())
- m_regs.lsr |= INS8250_LSR_FE;
- if (is_receive_parity_error())
- m_regs.lsr |= INS8250_LSR_PE;
- if ((m_regs.lsr & (INS8250_LSR_BI | INS8250_LSR_PE | INS8250_LSR_FE)) != 0)
- trigger_int(COM_INT_PENDING_RECEIVER_LINE_STATUS);
+ m_regs.lsr |= INS8250_LSR_DR;
- m_regs.rbr = get_received_char();
- trigger_int(COM_INT_PENDING_RECEIVED_DATA_AVAILABLE);
- }
+ if (is_receive_framing_error())
+ m_regs.lsr |= INS8250_LSR_FE;
+ if (is_receive_parity_error())
+ m_regs.lsr |= INS8250_LSR_PE;
+ if ((m_regs.lsr & (INS8250_LSR_BI | INS8250_LSR_PE | INS8250_LSR_FE | INS8250_LSR_OE)) != 0)
+ trigger_int(COM_INT_PENDING_RECEIVER_LINE_STATUS);
+
+ m_regs.rbr = get_received_char();
+ trigger_int(COM_INT_PENDING_RECEIVED_DATA_AVAILABLE);
}
void ins8250_uart_device::tra_complete()
@@ -566,6 +595,13 @@ void ins8250_uart_device::tra_complete()
void ins8250_uart_device::tra_callback()
{
m_txd = transmit_register_get_data_bit();
+
+ if (m_regs.lcr & INS8250_LCR_BREAK)
+ {
+ // in break mode, don't change transmitted bit
+ return;
+ }
+
if (m_regs.mcr & INS8250_MCR_LOOPBACK)
{
device_serial_interface::rx_w(m_txd);
@@ -583,7 +619,7 @@ void ins8250_uart_device::update_msr()
if (m_regs.mcr & INS8250_MCR_LOOPBACK)
{
- data = (((m_regs.mcr & (INS8250_MCR_OUT1|INS8250_MCR_OUT2)) << 4) | \
+ data = (((m_regs.mcr & (INS8250_MCR_OUT1|INS8250_MCR_OUT2)) << 4) |
((m_regs.mcr & INS8250_MCR_DTR) << 5) | ((m_regs.mcr & INS8250_MCR_RTS) << 3));
change = (m_regs.msr ^ data) >> 4;
if(!(m_regs.msr & 0x40) && (data & 0x40))
@@ -601,31 +637,31 @@ void ins8250_uart_device::update_msr()
trigger_int(COM_INT_PENDING_MODEM_STATUS_REGISTER);
}
-WRITE_LINE_MEMBER(ins8250_uart_device::dcd_w)
+void ins8250_uart_device::dcd_w(int state)
{
m_dcd = state;
update_msr();
}
-WRITE_LINE_MEMBER(ins8250_uart_device::dsr_w)
+void ins8250_uart_device::dsr_w(int state)
{
m_dsr = state;
update_msr();
}
-WRITE_LINE_MEMBER(ins8250_uart_device::ri_w)
+void ins8250_uart_device::ri_w(int state)
{
m_ri = state;
update_msr();
}
-WRITE_LINE_MEMBER(ins8250_uart_device::cts_w)
+void ins8250_uart_device::cts_w(int state)
{
m_cts = state;
update_msr();
}
-WRITE_LINE_MEMBER(ins8250_uart_device::rx_w)
+void ins8250_uart_device::rx_w(int state)
{
m_rxd = state;
@@ -635,12 +671,6 @@ WRITE_LINE_MEMBER(ins8250_uart_device::rx_w)
void ins8250_uart_device::device_start()
{
- m_out_tx_cb.resolve_safe();
- m_out_dtr_cb.resolve_safe();
- m_out_rts_cb.resolve_safe();
- m_out_int_cb.resolve_safe();
- m_out_out1_cb.resolve_safe();
- m_out_out2_cb.resolve_safe();
set_tra_rate(0);
set_rcv_rate(0);
@@ -687,7 +717,7 @@ void ins8250_uart_device::device_reset()
void ns16550_device::device_start()
{
- m_timeout = timer_alloc();
+ m_timeout = timer_alloc(FUNC(ns16550_device::timeout_expired), this);
ins8250_uart_device::device_start();
save_item(NAME(m_rintlvl));
save_item(NAME(m_rfifo));
@@ -711,13 +741,10 @@ void ns16550_device::device_reset()
ins8250_uart_device::device_reset();
}
-void ns16550_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+TIMER_CALLBACK_MEMBER(ns16550_device::timeout_expired)
{
- if(!id)
- {
- trigger_int(COM_INT_PENDING_CHAR_TIMEOUT);
- m_timeout->adjust(attotime::never);
- }
+ trigger_int(COM_INT_PENDING_CHAR_TIMEOUT);
+ m_timeout->adjust(attotime::never);
}
void ns16550_device::push_tx(u8 data)