From 97721a45be7fc463bc98f3b1e195a76f1a8e1fde Mon Sep 17 00:00:00 2001 From: Sergey Svishchev Date: Mon, 4 Jul 2016 21:03:30 +0300 Subject: [PATCH] null_modem: rtscts flow control + relevant fix to i8251 --- src/devices/bus/rs232/null_modem.cpp | 7 +++++-- src/devices/bus/rs232/null_modem.h | 2 ++ src/devices/machine/i8251.cpp | 4 ++-- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/src/devices/bus/rs232/null_modem.cpp b/src/devices/bus/rs232/null_modem.cpp index 4c5d7417a8b..63df2f925b7 100644 --- a/src/devices/bus/rs232/null_modem.cpp +++ b/src/devices/bus/rs232/null_modem.cpp @@ -15,7 +15,8 @@ null_modem_device::null_modem_device(const machine_config &mconfig, const char * m_rs232_stopbits(*this, "RS232_STOPBITS"), m_input_count(0), m_input_index(0), - m_timer_poll(nullptr) + m_timer_poll(nullptr), + m_rts(ASSERT_LINE) { } @@ -68,6 +69,8 @@ WRITE_LINE_MEMBER(null_modem_device::update_serial) output_dcd(0); output_dsr(0); output_cts(0); + + m_rts = ASSERT_LINE; } void null_modem_device::device_reset() @@ -99,7 +102,7 @@ void null_modem_device::queue() m_input_count = m_stream->input(m_input_buffer, sizeof(m_input_buffer)); } - if (m_input_count != 0) + if (m_input_count != 0 && m_rts == ASSERT_LINE) { transmit_register_setup(m_input_buffer[m_input_index++]); diff --git a/src/devices/bus/rs232/null_modem.h b/src/devices/bus/rs232/null_modem.h index aed62fb3aad..2db8b428879 100644 --- a/src/devices/bus/rs232/null_modem.h +++ b/src/devices/bus/rs232/null_modem.h @@ -15,6 +15,7 @@ public: virtual machine_config_constructor device_mconfig_additions() const override; virtual WRITE_LINE_MEMBER( input_txd ) override { device_serial_interface::rx_w(state); } + virtual WRITE_LINE_MEMBER( input_rts ) override { m_rts = (line_state) state; } DECLARE_WRITE_LINE_MEMBER(update_serial); @@ -46,6 +47,7 @@ private: UINT32 m_input_count; UINT32 m_input_index; emu_timer *m_timer_poll; + line_state m_rts; }; extern const device_type NULL_MODEM; diff --git a/src/devices/machine/i8251.cpp b/src/devices/machine/i8251.cpp index 7b0d272970d..3cb0f59a02c 100644 --- a/src/devices/machine/i8251.cpp +++ b/src/devices/machine/i8251.cpp @@ -416,8 +416,8 @@ WRITE8_MEMBER(i8251_device::command_w) 1 = transmit enable */ - m_rts_handler(!BIT(data, 5)); - m_dtr_handler(!BIT(data, 1)); + m_rts_handler(BIT(data, 5)); + m_dtr_handler(BIT(data, 1)); if (data & (1<<4)) {