Merge pull request #63 from mndza/fix-handoff-windows

apollo_fpga: fix handing off USB port to Apollo under Windows

apollo_fpga/__init__.py

@@ -7,6 +7,7 @@
 import os
 import time
 import usb.core
+import platform
 
 from .jtag  import JTAGChain
 from .spi   import DebugSPIConnection
@@ -129,6 +130,10 @@ def _request_handoff(cls, device):
         if stub_if is None:
             raise DebuggerNotFound("No Apollo stub interface found")
 
+        # In Windows, we first need to claim the target interface.
+        if platform.system() == "Windows":
+            usb.util.claim_interface(device, stub_if)
+
         # Send the request
         intf_number = stub_if.bInterfaceNumber
         REQUEST_APOLLO_ADV_STOP = 0xF0