3M C3266PW User's Guide download pdf (Page 31)

3M™ Multi-Touch Chassis Display User Guide 31

3M Touch Systems, Inc. Proprietary Information – TSD-39373B

APPENDIX A

3M™ PX USB Controller Communications

This appendix is intended for software developers only and discusses the fundamentals of

communicating with the 3M™ PX 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 appendix 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: This document assumes you are familiar with USB standards and modes of

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 PX controller and simplify the development of

custom drivers, 3M Touch Systems recommends you use the commands listed in this

appendix 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 PX

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. The computer can also send requests to the controller to change how it

operates or receives information about the controller. The controller issues a synchronous

report in response to some of these requests.

1 2 ... 26 27 28 29 30 31 32 33 34 35 36 ... 53 54

No comments

3M C3266PW User's Guide Page 31