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3M™ MicroTouch™ Controller SX112 Reference Guide
3M Touch Systems, Inc. Proprietary Information
The
command response
, which always follows the header, is a range of ASCII characters
depending on the type of command sent. Responses can be in many forms. For example,
one standard response is
0
(ASCII character ‘zero’ or 30 hexadecimal). This response
indicates a successful command completion for most commands, while it indicates a
failed completion for other commands. Refer to the firmware reference section for a
description of what the response indicates for
each
particular command.
Another standard response is
1
(ASCII character ‘one’ or 31 hexadecimal). In most cases,
this response indicates the command failed. The controller received an invalid command
that it could not execute.
Some possible reasons for a command failure include:
•
The command was not formatted correctly.
•
The system parameters were not set up to allow command execution.
•
The controller does not support the command.
The
terminator
is the last character of each response string and is an ASCII carriage
return CR. The hexadecimal code for the ASCII CR control character is 0D hexadecimal.
The value returned in the response will be the ASCII control character for a carriage
return, displayed on the screen as the cursor moving to the next line.
In this chapter, responses are shown as a string of ASCII characters consisting of a
header, the response, and a terminator as follows:
<SOH>
Response
<CR>
Controller Initialization
To initialize the SX serial controller for new development, 3M Touch Systems
recommends that the host system issue a Reset command whenever the host system is
powered on and is attempting to establish communication with the controller.
Firmware Commands
Developers may use this information when writing touch applications, developing custom
drivers or touch configurations, or testing their touch systems. Developers can use
firmware commands to initialize the controller, select operating modes, specify data
formats, and execute diagnostic functions.
Most touch systems users do
not
have to use firmware commands to use their touch
systems. For example, users can use 3M™ MicroTouch™ Software to calibrate the
sensor or to determine the controller type and firmware version.
Caution:
This document assumes you are familiar with firmware commands and how to
use them. Executing some commands may alter the performance of your touch system
and render it inoperable. You should be aware of the results before executing any
firmware commands.