Purge port buffers on device open call

1 files changed, 9 insertions, 0 deletions

diff --git a/pcserialport.c b/pcserialport.c
index 792f079..ef33aa9 100644
--- a/pcserialport.c
+++ b/pcserialport.c
@@ -78,6 +78,12 @@ smint32 serialPortOpen(const char * port_device_name, smint32 baudrate_bps)
                 smDebug(-1, Low, "Serial port error: failed to set port parameters");
                 return -1;
 	}
+
+    //flush any stray bytes from device receive buffer that may reside in it
+    //note: according to following page, delay before this may be necessary http://stackoverflow.com/questions/13013387/clearing-the-serial-ports-buffer
+    usleep(100000);
+    tcflush(port_handle,TCIOFLUSH);
+
     return port_handle;
 }
 
@@ -167,6 +173,9 @@ smint32 serialPortOpen(const char *port_device_name, smint32 baudrate_bps)
         return(-1);
     }
 
+    //flush any stray bytes from device receive buffer that may reside in it
+    PurgeComm((HANDLE)port_handle,PURGE_RXABORT|PURGE_RXCLEAR|PURGE_TXABORT|PURGE_TXCLEAR);
+
     return( (smint32)port_handle);
 }