diff --git a/Usb.cpp b/Usb.cpp
index ca81cf99..37914046 100644
--- a/Usb.cpp
+++ b/Usb.cpp
@@ -698,17 +698,20 @@ uint8_t USB::Configuring(uint8_t parent, uint8_t port, bool lowspeed) {
         // Allocate new address according to device class
         //bAddress = addrPool.AllocAddress(parent, false, port);
 
-        //if (!bAddress)
-        //        return USB_ERROR_OUT_OF_ADDRESS_SPACE_IN_POOL;
         uint16_t vid = udd->idVendor;
         uint16_t pid = udd->idProduct;
         uint8_t klass = udd->bDeviceClass;
-
+        uint8_t subklass = udd->bDeviceSubClass;
         // Attempt to configure if VID/PID or device class matches with a driver
+        // Qualify with subclass too.
+        //
+        // VID/PID & class tests default to false for drivers not yet ported
+        // subclass defaults to true, so you don't have to define it if you don't have to.
+        //
         for(devConfigIndex = 0; devConfigIndex < USB_NUMDEVICES; devConfigIndex++) {
                 if(!devConfig[devConfigIndex]) continue; // no driver
                 if(devConfig[devConfigIndex]->GetAddress()) continue; // consumed
-                if(devConfig[devConfigIndex]->VIDPIDOK(vid, pid) || devConfig[devConfigIndex]->DEVCLASSOK(klass)) {
+                if(devConfig[devConfigIndex]->DEVSUBCLASSOK(subklass) && (devConfig[devConfigIndex]->VIDPIDOK(vid, pid) || devConfig[devConfigIndex]->DEVCLASSOK(klass))) {
                         rcode = AttemptConfig(devConfigIndex, parent, port, lowspeed);
                         if(rcode != USB_DEV_CONFIG_ERROR_DEVICE_NOT_SUPPORTED)
                                 break;
@@ -724,7 +727,7 @@ uint8_t USB::Configuring(uint8_t parent, uint8_t port, bool lowspeed) {
         for(devConfigIndex = 0; devConfigIndex < USB_NUMDEVICES; devConfigIndex++) {
                 if(!devConfig[devConfigIndex]) continue;
                 if(devConfig[devConfigIndex]->GetAddress()) continue; // consumed
-                if(devConfig[devConfigIndex]->VIDPIDOK(vid, pid) || devConfig[devConfigIndex]->DEVCLASSOK(klass)) continue; // If this is true it means it must have returned USB_DEV_CONFIG_ERROR_DEVICE_NOT_SUPPORTED above
+                if(devConfig[devConfigIndex]->DEVSUBCLASSOK(subklass) && (devConfig[devConfigIndex]->VIDPIDOK(vid, pid) || devConfig[devConfigIndex]->DEVCLASSOK(klass))) continue; // If this is true it means it must have returned USB_DEV_CONFIG_ERROR_DEVICE_NOT_SUPPORTED above
                 rcode = AttemptConfig(devConfigIndex, parent, port, lowspeed);
 
                 //printf("ERROR ENUMERATING %2.2x\r\n", rcode);
diff --git a/UsbCore.h b/UsbCore.h
index 76d9d5ee..f514195c 100644
--- a/UsbCore.h
+++ b/UsbCore.h
@@ -150,6 +150,11 @@ public:
         virtual boolean DEVCLASSOK(uint8_t klass) {
                 return false;
         }
+
+        virtual boolean DEVSUBCLASSOK(uint8_t subklass) {
+                return true;
+        }
+
 };
 
 /* USB Setup Packet Structure   */
diff --git a/cdcftdi.cpp b/cdcftdi.cpp
index 13ca683f..8f07b358 100644
--- a/cdcftdi.cpp
+++ b/cdcftdi.cpp
@@ -246,7 +246,7 @@ uint8_t FTDI::Release() {
         bNumEP = 1;
         qNextPollTime = 0;
         bPollEnable = false;
-        return 0;
+        return pAsync->OnRelease(this);
 }
 
 uint8_t FTDI::Poll() {
diff --git a/cdcftdi.h b/cdcftdi.h
index 866e2d7d..fbb7396d 100644
--- a/cdcftdi.h
+++ b/cdcftdi.h
@@ -79,6 +79,7 @@ class FTDI;
 class FTDIAsyncOper {
 public:
         virtual uint8_t OnInit(FTDI *pftdi) = 0;
+        virtual uint8_t OnRelease(FTDI *pftdi) = 0;
 };
 
 
@@ -128,6 +129,11 @@ public:
 
         // UsbConfigXtracter implementation
         virtual void EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t proto, const USB_ENDPOINT_DESCRIPTOR *ep);
+
+        virtual boolean VIDPIDOK(uint16_t vid, uint16_t pid) {
+                return (vid == FTDI_VID && pid == FTDI_PID);
+        }
+
 };
 
 #endif // __CDCFTDI_H__
diff --git a/examples/testusbhostFAT/Arduino_Makefile_master b/examples/testusbhostFAT/Arduino_Makefile_master
index 7ada91a9..d35bb955 160000
--- a/examples/testusbhostFAT/Arduino_Makefile_master
+++ b/examples/testusbhostFAT/Arduino_Makefile_master
@@ -1 +1 @@
-Subproject commit 7ada91a90027ccb7558b74087fb68d3940ecf64d
+Subproject commit d35bb955e3818f0c14e47c8a1998003da8dc1b5a
diff --git a/examples/testusbhostFAT/RTClib b/examples/testusbhostFAT/RTClib
index b119b97e..7fd6a306 160000
--- a/examples/testusbhostFAT/RTClib
+++ b/examples/testusbhostFAT/RTClib
@@ -1 +1 @@
-Subproject commit b119b97e1484a08aebcf24e070113d78c82fb023
+Subproject commit 7fd6a306ca53d08bf53b2bbfc1b80eb056f2c55b
diff --git a/examples/testusbhostFAT/generic_storage b/examples/testusbhostFAT/generic_storage
index 72b5bf46..0b8e3076 160000
--- a/examples/testusbhostFAT/generic_storage
+++ b/examples/testusbhostFAT/generic_storage
@@ -1 +1 @@
-Subproject commit 72b5bf467a1c2479ba7354ee4d864e382c167425
+Subproject commit 0b8e3076b5a072251e01cfc6e6333b364d4e71e7
diff --git a/hidboot.h b/hidboot.h
index 0326bf25..b35df7cb 100644
--- a/hidboot.h
+++ b/hidboot.h
@@ -214,6 +214,14 @@ public:
 
         // UsbConfigXtracter implementation
         virtual void EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t proto, const USB_ENDPOINT_DESCRIPTOR *ep);
+
+        virtual boolean DEVCLASSOK(uint8_t klass) {
+                return (klass == USB_CLASS_HID);
+        }
+
+        virtual boolean DEVSUBCLASSOK(uint8_t subklass) {
+                return (subklass == BOOT_PROTOCOL);
+        }
 };
 
 template <const uint8_t BOOT_PROTOCOL>