3M™ MicroTouch™ Controller RX142 Reference Guide

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3M Touch Systems, Inc. Proprietary Information

The terminator is the last character of each command string and is an ASCII carriage

return CR. An ASCII CR control character is 0D hexadecimal. To enter a carriage return

ending the command sequence, use Enter or the key combination Ctrl M (^M).

This chapter lists each command as a string of ASCII control characters and printable

characters consisting of a header, the command, and a terminator as follows:

<SOH>Command<CR>

Receiving Responses from the Controller

After executing a command, the controller returns a response to the host system. Each

controller response consists of a header, the command response, and a terminator in the

following format:

<Header>Command Response<Terminator>

Note:

The following descriptions of header, response, and terminator, use 3M Touch

Systems terminal emulator key sequences. The format of controller responses varies

depending on the terminal emulation mode you are using.

The header is the first character in the response string and is the ASCII start-of-header

control character SOH. The hexadecimal code for the ASCII SOH control character is 01.

If you are working with an IBM PC compatible system in terminal mode, the SOH

control character returns a ☺ character to the sensor.

The 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. See 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 sensor as the cursor moving to the next line.