diff --git a/AVRsack/ASBuilder.swift b/AVRsack/ASBuilder.swift
index cc64167..e34e8b6 100644
--- a/AVRsack/ASBuilder.swift
+++ b/AVRsack/ASBuilder.swift
@@ -15,10 +15,10 @@ class ASBuilder {
     var termination : AnyObject?
     
     init() {
-        termination = NotificationCenter.defaultCenter.addObserverForName(NSTaskDidTerminateNotification,
-            object: nil, queue: nil, usingBlock:
-        { (notification: NSNotification) in
-            if notification.object as? NSTask == self.task {
+        termination = NotificationCenter.default.addObserver(forName: Task.didTerminateNotification,
+                                                                   object: nil, queue: nil, using:
+        { (notification: Notification) in
+            if notification.object as? Task == self.task {
                 if self.task!.terminationStatus == 0 {
                     if let cont = self.continuation {
                         self.continuation = nil
diff --git a/AVRsack/ASProjDoc.swift b/AVRsack/ASProjDoc.swift
index ab5a8b2..f9b0b29 100644
--- a/AVRsack/ASProjDoc.swift
+++ b/AVRsack/ASProjDoc.swift
@@ -94,10 +94,10 @@ class ASProjDoc: NSDocument, NSOutlineViewDelegate, NSMenuDelegate, NSOpenSavePa
         recentProgrammers   = userDefaults.object(forKey: kRecentProgrammersKey) as! [String]
         
         let nc          = NotificationCenter.default
-        themeObserver   = nc.addObserverForName(kBindingsKey, object: nil, queue: nil, usingBlock: { (NSNotification) in
+        themeObserver   = nc.addObserver(forName: NSNotification.Name(kBindingsKey), object: nil, queue: nil, using: { (NSNotification) in
             self.editor?.setKeyboardHandler(keyboardHandler)
         })
-        serialObserver  = nc.addObserverForName(kASSerialPortsChanged, object: nil, queue: nil, usingBlock: { (NSNotification) in
+        serialObserver  = nc.addObserver(forName: NSNotification.Name(kASSerialPortsChanged), object: nil, queue: nil, using: { (NSNotification) in
             if self.portTool != nil {
                 self.rebuildPortMenu()
             }
@@ -138,7 +138,7 @@ class ASProjDoc: NSDocument, NSOutlineViewDelegate, NSMenuDelegate, NSOpenSavePa
                 }
             }
         }
-        outlineViewSelectionDidChange(NSNotification(name: "", object: nil))
+        outlineViewSelectionDidChange(Notification(name: Notification.Name(""), object: nil))
         menuNeedsUpdate(boardTool.menu!)
         menuNeedsUpdate(progTool.menu!)
         rebuildPortMenu()
@@ -686,7 +686,7 @@ class ASProjDoc: NSDocument, NSOutlineViewDelegate, NSMenuDelegate, NSOpenSavePa
         keyboardHandler = ACEKeyboardHandler(rawValue: UInt(item.tag))!
         UserDefaults.standard.set(
             ACEKeyboardHandlerNames.humanName(for: keyboardHandler), forKey: kBindingsKey)
-        NotificationCenter.defaultCenter.postNotificationName(kBindingsKey, object: item)
+        NotificationCenter.default.post(name: NSNotification.Name(kBindingsKey), object: item)
     }
     
     override func validateUserInterfaceItem(_ anItem: NSValidatedUserInterfaceItem) -> Bool {
diff --git a/AVRsack/ASSerialWin.swift b/AVRsack/ASSerialWin.swift
index 1e58d9a..dc0070a 100644
--- a/AVRsack/ASSerialWin.swift
+++ b/AVRsack/ASSerialWin.swift
@@ -104,9 +104,9 @@ class ASSerialWin: NSWindowController {
         }
 
         let nc          = NotificationCenter.default
-        serialObserver  = nc.addObserverForName(kASSerialPortsChanged, object: nil, queue: nil, usingBlock: { (NSNotification) in
-            self.willChangeValueForKey("hasValidPort")
-            self.didChangeValueForKey("hasValidPort")
+        serialObserver  = nc.addObserver(forName: NSNotification.Name(kASSerialPortsChanged), object: nil, queue: nil, using: { (NSNotification) in
+            self.willChangeValue(forKey: "hasValidPort")
+            self.didChangeValue(forKey: "hasValidPort")
 
             if self.task == nil {
                 if self.hasValidPort {
@@ -116,10 +116,10 @@ class ASSerialWin: NSWindowController {
                 }
             }
         })
-        termination = NotificationCenter.defaultCenter.addObserverForName(NSTaskDidTerminateNotification,
-            object: nil, queue: nil, usingBlock:
-            { (notification: NSNotification) in
-                if notification.object as? NSTask == self.task {
+        termination = NotificationCenter.default.addObserver(forName: Task.didTerminateNotification,
+                                                                   object: nil, queue: nil, using:
+            { (notification: Notification) in
+                if notification.object as? Task == self.task {
                     self.task        = nil
                     self.portHandle  = nil
                 }
@@ -246,9 +246,9 @@ class ASSerialWin: NSWindowController {
         keyboardHandler = ACEKeyboardHandler(rawValue: UInt(item.tag))!
         UserDefaults.standard.set(
             ACEKeyboardHandlerNames.humanName(for: keyboardHandler), forKey: "Bindings")
-        NotificationCenter.defaultCenter.postNotificationName("Bindings", object: item)
+        NotificationCenter.default.post(name: Notification.Name("Bindings"), object: item)
     }
-    
+
     func validateUserInterfaceItem(anItem: NSValidatedUserInterfaceItem) -> Bool {
         if let menuItem = anItem as? NSMenuItem {
             if menuItem.action == Selector(("changeTheme:")) {