30 3M™ MicroTouch™ Controller EX Serial Reference Guide
3M Touch Systems, Inc. Proprietary Information – TSD-29087 Rev D
The communication parameters of the host system must match the present settings of the
controller when the command is given for it to be accepted and the changes
implemented.
The process of changing the parameters takes three steps:
•
The host system must first communicate with the controller using a matched set of
parameters.
•
The Parameter Set command is issued with the new parameters to the controller. The
new settings take effect immediately.
•
The host system must be changed to the new parameters in order to communicate
with the controller again.
Examples: <SOH>PN813<CR> Sets the serial line to no parity, eight data bits,
one stop bit, and 4800 baud.
<SOH>PN81<CR> Sets the parity, data bits, and stop bits; leaves the baud at its
previous value.
Caution: The settings are immediately written to NOVRAM, and all future
communication must occur at the new values. It is possible to set the parameters to
values that prevent future communication with the controller.
Response:
<SOH>0<CR> Positive response
Reset
Syntax:
<SOH>R<CR>
Description:
Initializes the hardware and the firmware, causes the controller to stop sending data, and
recalculates the environmental conditions (for example, stray and offset values). The
Reset command also cancels the Format Raw, Calibrate Raw, and Calibrate Extended
commands and returns the controller to normal operation.
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.
The amount of time needed to execute a Reset command ranges from 225 milliseconds to
800 milliseconds. Therefore, the application program should wait and be sure it receives
the command response before issuing another command to the controller following the
reset.
Response:
<SOH>0<CR> Positive response.
