Hello Max,
I wish I could be more help. We ended up making a major change to this project that has pushed it out and I have been focusing on hardware and postponed looking into this as I had a workaround using a custom .inf file and disabling driver signature enforcement for now. I was hoping maybe possibly it would be added to Harmony by the time I got back to it. Now we've ended up switching to another CPU because of RAM and ADC limitations. I did however receive the below response in my ticket that may be helpful. It seems Microchip added the Microsoft string descriptors to MLA but not to Harmony! I posted the MLA descriptors below as well for reference.
Sorry I could not be more help!
Martin
Microchip Ticket Support:
The "MLA" (Microchip Library of Applications) which provides software stacks on USB, TCP/IP, Graphics etc. for 8 & 16-bit PICs (so the PIC32 is not included anymore, since it uses Harmony now), also has an example for WinUSB supporting the new feature you described.
In case you wish to see how it's been implemented, you could do this:
> Download & install the MLA (latest version!), or at least the USB Framework & examples from its installation menu:
> Open the MPLAB X demo located by default under:
C:\microchip\mla\v2014_07_22\apps\usb\device\vendor_basic\firmware
> Look for the “IMPLEMENT_MICROSOFT_OS_DESCRIPTOR” configuration option. You can see the vendor specific descriptor in usb_descriptors.c
MLA Descriptors:
//Microsoft "OS Descriptor" - This descriptor is based on a Microsoft specific
//specification (not part of the standard USB 2.0 specs or class specs).
//Implementing this special descriptor allows WinUSB driver package installation
//to be automatic on Windows 8. For additional details, see:
//
const MS_OS_DESCRIPTOR MSOSDescriptor =
{
sizeof(MSOSDescriptor), //bLength - lenght of this descriptor in bytes
USB_DESCRIPTOR_STRING, //bDescriptorType - "string"
{'M','S','F','T','1','0','0'}, //qwSignature - special values that specifies the OS descriptor spec version that this firmware implements
GET_MS_DESCRIPTOR, //bMS_VendorCode - defines the "GET_MS_DESCRIPTOR" bRequest literal value
0x00 //bPad - always 0x00
};
//Extended Compat ID OS Feature Descriptor
const MS_COMPAT_ID_FEATURE_DESC CompatIDFeatureDescriptor =
{
//----------Header Section--------------
sizeof(CompatIDFeatureDescriptor), //dwLength
0x0100, //bcdVersion = 1.00
EXTENDED_COMPAT_ID, //wIndex
0x01, //bCount - 0x01 "Function Section(s)" implemented in this descriptor
{0,0,0,0,0,0,0}, //Reserved[7]
//----------Function Section 1----------
0x00, //bFirstInterfaceNumber: the WinUSB interface in this firmware is interface #0
0x01, //Reserved - fill this reserved byte with 0x01 according to documentation
{'W','I','N','U','S','B',0x00,0x00},//compatID - "WINUSB" (with two null terminators to fill all 8 bytes)
{0,0,0,0,0,0,0,0}, //subCompatID - eight bytes of 0
{0,0,0,0,0,0} //Reserved
};
//Extended Properties OS Feature Descriptor
const MS_EXT_PROPERTY_FEATURE_DESC ExtPropertyFeatureDescriptor =
{
//----------Header Section--------------
sizeof(ExtPropertyFeatureDescriptor), //dwLength
0x0100, //bcdVersion = 1.00
EXTENDED_PROPERTIES, //wIndex
0x0001, //wCount - 0x0001 "Property Sections" implemented in this descriptor
//----------Property Section 1----------
132, //dwSize - 132 bytes in this Property Section
0x00000001, //dwPropertyDataType (Unicode string)
40, //wPropertyNameLength - 40 bytes in the bPropertyName field
{'D','e','v','i','c','e','I','n','t','e','r','f','a','c','e','G','U','I','D', 0x0000}, //bPropertyName - "DeviceInterfaceGUID"
78, //dwPropertyDataLength - 78 bytes in the bPropertyData field (GUID value in UNICODE formatted string, with braces and dashes)
//The below value is the Device Interface GUID (a 128-bit long "globally unique identifier")
//Please modify the GUID value in your application before moving to production.
//When you change the GUID, you must also change the PC application software
//that connects to this device, as the software looks for the device based on
//VID, PID, and GUID. All three values in the PC application must match
//the values in this firmware.
//The GUID value can be a randomly generated 128-bit hexadecimal number,
//formatted like the below value. The actual value is not important,
//so long as it is almost certain to be globally unique, and matches the
//PC software that communicates with this firmware.
{'{','5','8','d','0','7','2','1','0','-','2','7','c','1','-','1','1','d','d','-','b','d','0','b','-','0','8','0','0','2','0','0','c','9','a','6','6','}',0x0000} //bPropertyData - this is the actual GUID value. Make sure this matches the PC application code trying to connect to the device.
};
