Watson Industries, Inc.
DMS-EGP02 Rev A 03/28/2008
11
Output Logic Commands
Initialization lasts 5 seconds, during which time the "Ready" signal is set low (0v). Once
Initialization is complete, the "Ready" signal is set high (+5VDC). The ready signal is on pin 9 of
the 25 pin connector.
Input Logic Commands
The DMS also has several digital inputs that are all activated by connecting to signal ground. The
user should only apply a ground because all the inputs have a internal pull-up resistor to +5VDC.
The pins are as follows:
a) Initialization - Resets all angle integrators. The unit should be in a non-accelerated
condition if this command is given. Leave pin open if not in use. Ground to command.
b) Reference - An alternate set of sensor information primarily intended as an
instrumentation mode. Leave pin open if not in use. Ground to command.
c) Free Inertial Mode – In this mode, the attitude is computed from gyro data only. Free
mode is used when extreme accelerations are expected. Leave pin open if not in use.
Ground to command.
NOTE: The digital logic inputs are all disabled if any one equivalent serial command is sent via
RS-232. This is to prevent hardware/software conflicts.
