diff --git a/System.Device.I2c.Slave/System.Device.I2c.Slave.nfproj b/System.Device.I2c.Slave/System.Device.I2c.Slave.nfproj
index bc53860..6205319 100644
--- a/System.Device.I2c.Slave/System.Device.I2c.Slave.nfproj
+++ b/System.Device.I2c.Slave/System.Device.I2c.Slave.nfproj
@@ -53,7 +53,7 @@
   </ItemGroup>
   <ItemGroup>
     <Reference Include="mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.CoreLibrary.2.0.0-preview.35\lib\netnano1.0\mscorlib.dll</HintPath>
+      <HintPath>..\packages\nanoFramework.CoreLibrary.2.0.0-preview.39\lib\netnano1.0\mscorlib.dll</HintPath>
     </Reference>
   </ItemGroup>
   <Import Project="$(NanoFrameworkProjectSystemPath)NFProjectSystem.CSharp.targets" Condition="Exists('$(NanoFrameworkProjectSystemPath)NFProjectSystem.CSharp.targets')" />
diff --git a/System.Device.I2c.Slave/packages.config b/System.Device.I2c.Slave/packages.config
index c1985bc..5336b0f 100644
--- a/System.Device.I2c.Slave/packages.config
+++ b/System.Device.I2c.Slave/packages.config
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="2.0.0-preview.35" targetFramework="netnano1.0" />
+  <package id="nanoFramework.CoreLibrary" version="2.0.0-preview.39" targetFramework="netnano1.0" />
   <package id="Nerdbank.GitVersioning" version="3.9.50" developmentDependency="true" targetFramework="netnano1.0" />
 </packages>
\ No newline at end of file
diff --git a/System.Device.I2c.Slave/packages.lock.json b/System.Device.I2c.Slave/packages.lock.json
index f85cb78..e04980a 100644
--- a/System.Device.I2c.Slave/packages.lock.json
+++ b/System.Device.I2c.Slave/packages.lock.json
@@ -4,9 +4,9 @@
     ".NETnanoFramework,Version=v1.0": {
       "nanoFramework.CoreLibrary": {
         "type": "Direct",
-        "requested": "[2.0.0-preview.35, 2.0.0-preview.35]",
-        "resolved": "2.0.0-preview.35",
-        "contentHash": "l3LZs5zLeYKP+21DmVykOBWQvcLWOzgOls2JU6R2mRb2cz1+SitRCaEC5bTEJHs888JdHi3xWMVe3GkRzZ/2Lg=="
+        "requested": "[2.0.0-preview.39, 2.0.0-preview.39]",
+        "resolved": "2.0.0-preview.39",
+        "contentHash": "rkXOwaEq6GIm+dKZ7ICMrG23mln482vRXyDtaNfAeBpgGcgiuFJrbw7w0TTZ2DNhw1CUWlCWZZbXi6+/NHdpLg=="
       },
       "Nerdbank.GitVersioning": {
         "type": "Direct",
diff --git a/nanoFramework.System.Device.I2c.Slave.nuspec b/nanoFramework.System.Device.I2c.Slave.nuspec
index 5561ccd..ed945ec 100644
--- a/nanoFramework.System.Device.I2c.Slave.nuspec
+++ b/nanoFramework.System.Device.I2c.Slave.nuspec
@@ -20,7 +20,7 @@ This package requires a target with System.Device.I2c.Slave v$nativeVersion$ (ch
     <tags>nanoFramework C# csharp netmf netnf I2c</tags>
     <dependencies>
       <group targetFramework=".NETnanoFramework1.0">
-        <dependency id="nanoFramework.CoreLibrary" version="2.0.0-preview.35" />
+        <dependency id="nanoFramework.CoreLibrary" version="2.0.0-preview.39" />
       </group>
     </dependencies>
   </metadata>