PORTS Forum

Ports and Interfaces => USB => Topic started by: lcpoon on September 23, 2011, 11:23:24 am

Title: USB Communication
Post by: lcpoon on September 23, 2011, 11:23:24 am

I have two HIDs with same VID, same PID but different Serial number connected to the host. Is the host able to detect and to communicate with these 2 HIDs individually?

I am using mcHID.dll where VID + PID are used to write to/ read from the HID device. How to make use of the VID + PID + Serial number information to write to/ read from dedicated HID in my case here?

Title: Re: USB Communication
Post by: Jan Axelson on September 23, 2011, 02:33:24 pm

I haven't used mchid.dll, but a host can open a handle to each HID and use the handle to communicate with that HID. You don't need to use the serial numbers unless you need to identify specific devices or know which device is which after rebooting.

HidD_GetSerialNumberString returns the serial number.

Jan