3M™ MicroTouch™ Controller EX712 Reference Guide
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3M Touch Systems, Inc. Proprietary Information
Commands to the controller are sent on the signal
Receive Data
(RXD) line as a serial
data stream. For each command it receives, the controller sends a response to the host on
the signal
Transmit Data
(TXD) line also as a serial data stream.
Sending Commands to the Controller
When you send a command to the controller, you must use the correct command format.
The general format of a command is as follows:
<Header>Command<Terminator>
Note:
The following descriptions of header, command, and terminator, use 3M Touch
Systems terminal emulator key sequences. You may need to enter the sequence in a
different format, depending on your emulator.
The
header
is the first character in the command string and is the ASCII start-of-header
control character SOH. The hexadecimal code for the ASCII SOH control character is 01.
To start the command sequence, use the key combination Ctrl A (^A). If you are working
with an IBM PC compatible system, the Ctrl A key combination immediately returns an
ASCII
☺
character.
The
command
, which always follows the header, consists of ASCII uppercase letters and
numbers only (printable characters).
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 or acknowledgment 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.
