This article explains where to find information about Elo's serial hardware diagnostic tool, Comdump

Comdump is a legacy utility offered by Elo to diagnose serial port connections with Elo serial touch controllers. This utility and usage information is no longer supported and is only being provided as a courtesy. 
 
The comdump diagnostic will tell you if the touchscreen, the serial touch controller, the computer's serial COM port and the associated cabling are connected and functioning properly. This is only for Elo's older Smartset compatible controllers.

Download the  latest version of comdump.exe (7K) . You should save the file where it can be accessed easily - either to a USB flash drive or to the root of your hard drive. comdump is a 32-bit only DOS application. You will need to disable the Elo driver so you can access the COM port from a command prompt. NOTE: This utility was originally designed to be ran on DOS but will also run on Windows NT, Windows 2K, and Windows XP Operating Systems. It may or may not function on other Windows versions.





Here is a sample of the header screen:


Diagnosing







Elo Touch Solutions drivers will not operate if the DSR and CTS signals are not present (unless the hardware handshaking is disabled).