Px5Nnn Controller Usb Communications; Overview Of Usb Firmware Communications; Communication Basics - 3M PX5 Series Reference Manual

3M™ Multi-Touch ASIC Controller Reference Guide
CHAPTER 3
3M™ PX5nnn Controller USB
Communications
This chapter is intended for software developers only and discusses the fundamentals of
communicating with the 3M™ PX5nnn USB controller. The firmware commands, which
are usually issued by a driver or utility program on the host system, control the operation
of the controller. This chapter lists the recommended firmware commands and describes
how to use each of these commands.

Overview of USB Firmware Communications

Developers may use this information when writing touch applications, developing custom
drivers or touch configurations, or testing their touch systems. Developers can issue
commands to initialize the controller, select operating modes, and execute diagnostic
functions.
Note:
communication with USB devices, as well as firmware commands and how to use them.
Executing some commands may alter the performance of your sensor and render it
inoperable. You should be aware of the results before executing any firmware
commands.
To optimize the performance of the PX5nnn controller and simplify the development of
custom drivers, 3M Touch Systems recommends you use the commands listed in this
chapter for current development.

Communication Basics

This section provides information on sending firmware commands to the controller and
interpreting the responses that the controller returns. The default operation of the PX5nnn
controller is USB Rev 2.0 full speed.
The USB command set is implemented by using vendor requests and vendor reports, i.e.,
vendor specific transactions. The controller issues some reports without prompting the
computer.
This document assumes you are familiar with USB standards and modes of
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