From 36269097862c81753e4c9ddd012c04ce2ca17360 Mon Sep 17 00:00:00 2001
From: Charl Wentzel <charl.wentzel@vodamail.co.za>
Date: Mon, 4 Mar 2019 16:42:29 +0200
Subject: [PATCH] Important Update: - Added SendEnable (vir RTS pin) for
 TTL/RS485 converter - Bug fix: Check for Handle->InTimeout before force
 output

---
 SelectableCore.cpp | 32 +++++++++++++++++++++++++++++---
 SelectableCore.h   |  1 +
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/SelectableCore.cpp b/SelectableCore.cpp
index 5f36109..f7dd274 100644
--- a/SelectableCore.cpp
+++ b/SelectableCore.cpp
@@ -128,6 +128,8 @@ bool  CSelectableCore::Init( CDataMember * FunctionConfig )
                     FlowCtrl = HW_FLOWCTRL;
                 else if (!strcasecmp( FlowCtrlText, "software" ))
                     FlowCtrl = SW_FLOWCTRL;
+                else if (!strcasecmp( FlowCtrlText, "rs485" ))
+                    FlowCtrl = RS485_FLOWCTRL;
                 else
                     FlowCtrl = NO_FLOWCTRL;
 
@@ -652,6 +654,12 @@ THandle * CSelectableCore::OpenSerialPort( THandle * Handle )
         return NULL;
     }
 
+    // Set Send Enable (via RTS) for RS485
+    if ((Handle->Type == ctSerial) && (Handle->FlowCtrl == RS485_FLOWCTRL)) {
+        int sercmd = TIOCM_RTS;
+        ioctl( Handle->FD, TIOCMBIS, &sercmd );
+    }
+
     // Log Event
     if (Log)  Log->Message( LogLevel, dlMedium, "%s/%s: Handle '%s' - Serial Port opened [%s]",
                             ProcessName, Name, Handle->Name, Handle->Path );
@@ -1748,6 +1756,12 @@ bool CSelectableCore::Close( THandle * Handle, bool QuickReopen )
         }
     }
 
+    // Set Send Enable (via RTS) for RS485
+    if ((Handle->Type == ctSerial) && (Handle->FlowCtrl == RS485_FLOWCTRL)) {
+        int sercmd = TIOCM_RTS;
+        ioctl( Handle->FD, TIOCMBIC, &sercmd );
+    }
+
     // Close Handle
     if (Handle->Type == ctUDPremote) {
         Fail = false;
@@ -2099,10 +2113,22 @@ bool CSelectableCore::Write( THandle * Handle )
         {
             // Write directly to handle / socket
             errno = 0;
-            if ((Handle->Type == ctUDPclient)|| (Handle->Type == ctUDPremote)) {
+            if ((Handle->Type == ctUDPclient) || (Handle->Type == ctUDPremote)) {
                 Len = Handle->OutBuffer->Peek( &Data );
                 BytesWritten = WriteToUDP( Handle, Data, Len, true );
             }
+            else if ((Handle->Type == ctSerial) && (Handle->FlowCtrl == RS485_FLOWCTRL)) {
+                // Set Send Enable (via RTS pin) when sending data
+                int sercmd = TIOCM_RTS;
+                ioctl( Handle->FD, TIOCMBIC, &sercmd );
+                usleep( 1000 );
+
+                BytesWritten = Handle->OutBuffer->WriteToFD( Handle->FD );
+
+                tcdrain( Handle->FD );
+                usleep( 1000 );
+                ioctl( Handle->FD, TIOCMBIS, &sercmd );
+            }
             else {
                 BytesWritten = Handle->OutBuffer->WriteToFD( Handle->FD );
             }
@@ -2163,7 +2189,7 @@ bool CSelectableCore::ProcessInputBuffer( THandle * Handle, bool Force )
     }
 
     // Check if forced processed
-    if (Force || !Handle->InMarkerLen)
+    if (Force || (!Handle->InMarkerLen && !Handle->InTimeout))
     {
         // Show Packet
         Len = Handle->InBuffer->Peek( &Data );
@@ -2180,7 +2206,7 @@ bool CSelectableCore::ProcessInputBuffer( THandle * Handle, bool Force )
         // Clear processed bytes from buffer
         Handle->InBuffer->Clear( Len );
     }
-    else
+    else if (Handle->InMarkerLen)
     {
         // Search for end of packet marker
         while (Handle->InBuffer->FindStr( Handle->InMarker, Handle->InMarkerLen, Pos ))
diff --git a/SelectableCore.h b/SelectableCore.h
index 50ee239..cc97344 100644
--- a/SelectableCore.h
+++ b/SelectableCore.h
@@ -37,6 +37,7 @@ const char ConnectStateName[][15] = { "None", "OpenRequest", "WaitingToOpen", "O
 #define NO_FLOWCTRL     0
 #define HW_FLOWCTRL     1
 #define SW_FLOWCTRL     2
+#define RS485_FLOWCTRL  3
 
 //---------------------------------------------------------------------------