To view the USB vendor and product ids in Mac OS X, run the System Report, or USB Mac Probe utility as shown below:

System Report

For pre Mac OS X Lion you select the 'More Info' option first then the System Report.

Once the system report is shown expand the USB devices and locate the touch screen from the listed USB controllers.

In this example we have highlighted the hub on which a USB LT1423p monitor is connected.  This monitor utilises both a touch and Wacom pen as listed in the information panel with the vendor and product id highlighted.

USB Mac Prober

This utility can be used to show key elements of all the USB devices on a Mac system.

To capture USB configuration data on a Mac system download the USB Prober for either Snow Leopard or Lion (and above) and invoke the application. Once invoked, select the Bus Probe tab:

and use the Save Output option to save the entire USB probe profile to a log file and send us the log file:

Driver device configuration 

For UPDD to recognise a device (such as the ones in the System Report above) the same vendor and product id must be held against the supported devices for any given build of our software.

The 'upddutils pnpinfo' command can be used to list the supported devices along with their vendor and product ids as shown below: