From 980038c3ea2f7ce387e4c29aeb8adfea70c1e8de Mon Sep 17 00:00:00 2001
From: Tobias Kaupat <tobiall@niondir.de>
Date: Fri, 2 Mar 2018 16:35:56 +0100
Subject: [PATCH] Allow to set initial RTS and DTR state after connect

---
 serial.go         | 10 ++++++----
 serial_unix.go    |  3 +++
 serial_windows.go |  8 ++++++--
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/serial.go b/serial.go
index 3e4f3b1..674069b 100644
--- a/serial.go
+++ b/serial.go
@@ -74,10 +74,12 @@ func GetPortsList() ([]string, error) {
 
 // Mode describes a serial port configuration.
 type Mode struct {
-	BaudRate int      // The serial port bitrate (aka Baudrate)
-	DataBits int      // Size of the character (must be 5, 6, 7 or 8)
-	Parity   Parity   // Parity (see Parity type for more info)
-	StopBits StopBits // Stop bits (see StopBits type for more info)
+	BaudRate   int      // The serial port bitrate (aka Baudrate)
+	DataBits   int      // Size of the character (must be 5, 6, 7 or 8)
+	Parity     Parity   // Parity (see Parity type for more info)
+	StopBits   StopBits // Stop bits (see StopBits type for more info)
+	InitialRTS bool     // Initial state for RTS
+	InitialDTR bool     // Initial state for DTR
 }
 
 // Parity describes a serial port parity setting
diff --git a/serial_unix.go b/serial_unix.go
index d7c7078..2f7e1d1 100644
--- a/serial_unix.go
+++ b/serial_unix.go
@@ -235,6 +235,9 @@ func nativeOpen(portName string, mode *Mode) (*unixPort, error) {
 	// Explicitly disable RTS/CTS flow control
 	setTermSettingsCtsRts(false, settings)
 
+	port.SetDTR(mode.InitialDTR)
+	port.SetRTS(mode.InitialRTS)
+
 	if port.setTermSettings(settings) != nil {
 		port.Close()
 		return nil, &PortError{code: InvalidSerialPort}
diff --git a/serial_windows.go b/serial_windows.go
index af9a620..dd0715c 100644
--- a/serial_windows.go
+++ b/serial_windows.go
@@ -451,9 +451,13 @@ func nativeOpen(portName string, mode *Mode) (*windowsPort, error) {
 		return nil, &PortError{code: InvalidSerialPort}
 	}
 	params.Flags &= dcbRTSControlDisbaleMask
-	params.Flags |= dcbRTSControlEnable
+	if mode.InitialRTS {
+		params.Flags |= dcbRTSControlEnable
+	}
 	params.Flags &= dcbDTRControlDisableMask
-	params.Flags |= dcbDTRControlEnable
+	if mode.InitialDTR {
+		params.Flags |= dcbDTRControlEnable
+	}
 	params.Flags &^= dcbOutXCTSFlow
 	params.Flags &^= dcbOutXDSRFlow
 	params.Flags &^= dcbDSRSensitivity