diff options
Diffstat (limited to 'src/mame/drivers/eispc.cpp')
-rw-r--r-- | src/mame/drivers/eispc.cpp | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/src/mame/drivers/eispc.cpp b/src/mame/drivers/eispc.cpp index f009b9ecf32..eeca78cf408 100644 --- a/src/mame/drivers/eispc.cpp +++ b/src/mame/drivers/eispc.cpp @@ -536,7 +536,11 @@ TIMER_CALLBACK_MEMBER(epc_state::rxtxclk_w) m_kbd8251->write_rxc(m_8251rxtx_clk_state); m_kbd8251->write_txc(m_8251rxtx_clk_state); - if (!m_8251dtr_state) m_uart->rclk_w(m_8251rxtx_clk_state); + // The EPC PCB has an option to support a custom receive clock for the INS8250 apart from the TX clock through a mux controlled + // by the DTR pin of the I8251. The ins8250 device doesn't support RCLK as it is considerd implicitly as the same as BAUDOUT + // First attempt to support this in INS8250 by lifting out the BRG from deserial was reverted due to lots of regressions. + // We probably need to remove diserial dependencies completely from ins8250 or implement BRG hooks in diserial.cpp. + // if (!m_8251dtr_state) m_uart->rclk_w(m_8251rxtx_clk_state); // TODO: fix RCLK support in INS8250 m_8251rxtx_clk_state = !m_8251rxtx_clk_state; @@ -852,7 +856,7 @@ void epc_state::epc(machine_config &config) }); m_kbd8251->dtr_handler().set([this](bool state) // Controls RCLK for INS8250, either 19.2KHz or INS8250 BAUDOUT { - LOGCOM("KBD DTR: %d\n", state ? 1 : 0); // TODO: Implement clock selection mux, need to check what state does what + LOGCOM("KBD DTR: %d\n", state ? 1 : 0); m_8251dtr_state = state; }); @@ -934,7 +938,7 @@ void epc_state::epc(machine_config &config) FLOPPY_CONNECTOR(config, m_floppy_connectors[1], epc_sd_floppies, "525sd", epc_floppy_formats); //SOFTWARE_LIST(config, "epc_flop_list").set_original("epc_flop"); - // system board UART TODO: Implement the descrete "Baud Rate Clock" from schematics that generates clocks for the 8250 + // system board UART INS8250(config, m_uart, XTAL(18'432'000) / 10); // TEW crystal marked X2 verified. TODO: Let 8051 DTR control RCLK (see above) m_uart->out_tx_callback().set("com1", FUNC(rs232_port_device::write_txd)); m_uart->out_dtr_callback().set("com1", FUNC(rs232_port_device::write_dtr)); @@ -946,7 +950,7 @@ void epc_state::epc(machine_config &config) if ((m_io_j10->read() & 0x30) == 0x20) { LOGCOM("UART IRQ4: %d\n", state); m_pic8259->ir4_w(state); } // Factory setting if ((m_io_j10->read() & 0xc0) == 0x80) { LOGCOM("UART IRQ7: %d\n", state); m_pic8259->ir7_w(state); } }); - m_uart->out_baudout_callback().set([this](int state){ if (m_8251dtr_state) m_uart->rclk_w(state); }); + // m_uart->out_baudout_callback().set([this](int state){ if (m_8251dtr_state) m_uart->rclk_w(state); }); // TODO: Fix INS8250 BAUDOUT pin support rs232_port_device &rs232(RS232_PORT(config, "com1", default_rs232_devices, nullptr)); rs232.rxd_handler().set(m_uart, FUNC(ins8250_uart_device::rx_w)); |