From e0cf05f74aebbc16cfb864c173845f10a5e805a1 Mon Sep 17 00:00:00 2001
From: petermcs <petermcs@1e814d3a-8a88-4260-be86-c0dc25669c1e>
Date: Sat, 14 Jan 2012 12:28:44 +0000
Subject: [PATCH] Added in 76800 baud rate as it works on Win 7 with the B&B
 Electronics USOPTL4 USB adaptor that I have, YMMV. Added gettimeofday()
 function to allow me build with VS2008 C++ Express Edition

---
 bacnet-stack/demo/mstpcap/main.c | 73 ++++++++++++++++++++++++++++++++
 bacnet-stack/ports/win32/rs485.c | 23 ++++++++++
 2 files changed, 96 insertions(+)

diff --git a/bacnet-stack/demo/mstpcap/main.c b/bacnet-stack/demo/mstpcap/main.c
index d2e645f5..abb16178 100644
--- a/bacnet-stack/demo/mstpcap/main.c
+++ b/bacnet-stack/demo/mstpcap/main.c
@@ -507,6 +507,79 @@ static void write_global_header(
     }
 }
 
+#if defined(_MSC_VER)
+
+/* 
+ * Missing gettimeofday function for compiling with MS Visual Studio
+ * Visual C++ Express Edition.
+ * Courtesy of the Unix to Windows Porting Dictionary for HPC
+ * at http://suacommunity.com/dictionary/gettimeofday-entry.php
+ */
+
+#if defined(_MSC_VER) || defined(_MSC_EXTENSIONS)
+  #define DELTA_EPOCH_IN_MICROSECS  11644473600000000Ui64
+#else
+  #define DELTA_EPOCH_IN_MICROSECS  11644473600000000ULL
+#endif
+ 
+struct timezone
+{
+  int  tz_minuteswest; /* minutes W of Greenwich */
+  int  tz_dsttime;     /* type of dst correction */
+};
+ 
+// Definition of a gettimeofday function
+ 
+int gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+// Define a structure to receive the current Windows filetime
+  FILETIME ft;
+ 
+// Initialize the present time to 0 and the timezone to UTC
+  unsigned __int64 tmpres = 0;
+  static int tzflag = 0;
+ 
+  if (NULL != tv)
+  {
+    GetSystemTimeAsFileTime(&ft);
+ 
+// The GetSystemTimeAsFileTime returns the number of 100 nanosecond 
+// intervals since Jan 1, 1601 in a structure. Copy the high bits to 
+// the 64 bit tmpres, shift it left by 32 then or in the low 32 bits.
+    tmpres |= ft.dwHighDateTime;
+    tmpres <<= 32;
+    tmpres |= ft.dwLowDateTime;
+ 
+// Convert to microseconds by dividing by 10
+    tmpres /= 10;
+ 
+// The Unix epoch starts on Jan 1 1970.  Need to subtract the difference 
+// in seconds from Jan 1 1601.
+    tmpres -= DELTA_EPOCH_IN_MICROSECS;
+ 
+// Finally change microseconds to seconds and place in the seconds value. 
+// The modulus picks up the microseconds.
+    tv->tv_sec = (long)(tmpres / 1000000UL);
+    tv->tv_usec = (long)(tmpres % 1000000UL);
+  }
+ 
+  if (NULL != tz)
+  {
+    if (!tzflag)
+    {
+      _tzset();
+      tzflag++;
+    }
+  
+// Adjust for the timezone west of Greenwich
+      tz->tz_minuteswest = _timezone / 60;
+    tz->tz_dsttime = _daylight;
+  }
+ 
+  return 0;
+}
+#endif
+
 static void write_received_packet(
     volatile struct mstp_port_struct_t *mstp_port)
 {
diff --git a/bacnet-stack/ports/win32/rs485.c b/bacnet-stack/ports/win32/rs485.c
index cb5e674f..4b4babcf 100644
--- a/bacnet-stack/ports/win32/rs485.c
+++ b/bacnet-stack/ports/win32/rs485.c
@@ -303,6 +303,14 @@ uint32_t RS485_Get_Baud_Rate(
             return 128000;
         case CBR_256000:
             return 256000;
+        case 76800:
+            /* See comments in RS485_Set_Baud_Rate() below
+             * also look at definition of CBR_xx in winbase.h
+             * some serial drivers will only support the defined
+             * baud rates but others will try and configure the
+             * requested baud rate (or as close as they can get)
+             */
+            return 76800;
         case CBR_9600:
         default:
             return 9600;
@@ -366,6 +374,21 @@ bool RS485_Set_Baud_Rate(
         case 256000:
             RS485_Baud = CBR_256000;
             break;
+        case 76800:
+            /* I'm using the B&B Electronics USOPTL4 USB RS485 adapter
+             * on Win 7 and building with VS2008 Express Edition and it
+             * seems to work for the most part if I use the following.
+             * I get the occasional data errors especially if the devices
+             * are transmitting with 1 stop bit (some devices receive with
+             * 1 stop bit but effectivly end up transmitting with 2 stop
+             * bits, usually because of synchroisation issues in some UARTs
+             * which mean that if you wait until the serialiser has finished 
+             * with the current character and then load the TX buffer it has
+             * to wait until the next bit boundary to start transmitting.
+             * PMcS
+             */
+            RS485_Baud = 76800;
+            break;
         default:
             valid = false;
             break;