diff --git a/AVRsack/ASBuilder.swift b/AVRsack/ASBuilder.swift
index 7443d41..880aeba 100644
--- a/AVRsack/ASBuilder.swift
+++ b/AVRsack/ASBuilder.swift
@@ -138,10 +138,9 @@ class ASBuilder {
                 logOut.writeData("Opening \(port) at 1200 baud\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
             }
             if let dummyConnection = ASSerial.openPort(port, withSpeed: 1200) {
-                ASSerial.restorePort(dummyConnection.fileDescriptor)
-                dummyConnection.closeFile()
-                sleep(5)
-                for (var retry=0; retry < 10; ++retry) {
+                close(dummyConnection.fileDescriptor)
+                for (var retry=0; retry < 40; ++retry) {
+                    usleep(250000)
                     if (NSFileManager.defaultManager().fileExistsAtPath(port)) {
                         if verbosity > 0 {
                             logOut.writeData("Found port \(port) after \(retry) attempts.\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
diff --git a/AVRsack/ASProjDoc.swift b/AVRsack/ASProjDoc.swift
index 10cad1a..16ac2b3 100644
--- a/AVRsack/ASProjDoc.swift
+++ b/AVRsack/ASProjDoc.swift
@@ -474,7 +474,9 @@ class ASProjDoc: NSDocument, NSOutlineViewDelegate, NSMenuDelegate {
                     ASSerialWin.portAvailableAfterUpload(self.port)
                 })
             }
-            self.builder.uploadProject(self.board, programmer:self.programmer, port:ASSerial.fileNameForPort(self.port))
+            dispatch_async(dispatch_get_main_queue(), {
+                self.builder.uploadProject(self.board, programmer:self.programmer, port:ASSerial.fileNameForPort(self.port))
+            })
         }
         buildProject(sender)
     }
diff --git a/AVRsack/ASSerial.mm b/AVRsack/ASSerial.mm
index 8d66b04..5914ec8 100644
--- a/AVRsack/ASSerial.mm
+++ b/AVRsack/ASSerial.mm
@@ -58,9 +58,10 @@ NSString * kASSerialPortsChanged = @"PortsChanged";
     newAttr = origAttr;
     cfmakeraw(&newAttr);
     cfsetspeed(&newAttr, speed);
-    newAttr.c_cflag |= CS8 | CCTS_OFLOW | CRTS_IFLOW;
-    newAttr.c_cflag &= ~(PARENB);
+    newAttr.c_cflag &= ~(PARENB | CSIZE | CSTOPB | CRTSCTS);
+    newAttr.c_cflag |= CS8;
     tcsetattr(fd, TCSANOW, &newAttr);
+    tcsetattr(fd, TCSAFLUSH, &newAttr);
     if (!savedAttrs) {
         savedAttrs = [NSMutableDictionary dictionary];
     }