What would be the best way to have a USB HID device masquerade as a USB Serial HID device?

NTDEV
1

I have a USB HID device for which I have written a KMDF filter driver
(based on the toaster generic filter sample) that intercepts all
write/reads between the user app and the driver. The driver translates
messages from the user app, written for a different USB HID device, into
the format required for my device and then translates my device’s response
into the format expected to be received by the user app. This is working
fine. I now want my device to masquerade as a USB Serial HID device that
uses a COM port while my existing driver continues to handle the required
translations between user app and device. Will I need to write a virtual
COM driver to work with my device or can I use an existing driver like the
FTDI one or is there a better way to accomplish this?

Randy

2

You will have to write a virtual com driver or emulate enough of the CDC spec and enumerate a pdo to load usbser.sys

Sent from my Windows 10 phone

From: Randy Lewismailto:xxxxx
Sent: Sunday, April 24, 2016 8:04 AM
To: Windows System Software Devs Interest Listmailto:xxxxx
Subject: [ntdev] What would be the best way to have a USB HID device masquerade as a USB Serial HID device?

I have a USB HID device for which I have written a KMDF filter driver (based on the toaster generic filter sample) that intercepts all write/reads between the user app and the driver. The driver translates messages from the user app, written for a different USB HID device, into the format required for my device and then translates my device’s response into the format expected to be received by the user app. This is working fine. I now want my device to masquerade as a USB Serial HID device that uses a COM port while my existing driver continues to handle the required translations between user app and device. Will I need to write a virtual COM driver to work with my device or can I use an existing driver like the FTDI one or is there a better way to accomplish this?

Randy
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