Introduction
7. Wake and Enable the device for operation.
(a) After setting up the controls signals for the DRV8846, enabling the DRV8846 requires selecting
both the WAKE and ENABLE buttons. When the WAKE button or ENABLE button are selected, the
circle to the left of the button will toggle from red to green.
(b) The WAKE button, which controls the nSLEEP pin, is used to wake the DRV8846. The ENABLE
button, which controls the nENBL pin, is used to enable the DRV8846 outputs.
(c) A message which states that
*Both WAKE and ENABLE must be Green to enable the motor control
buttons
will be visible until both the WAKE and ENABLE buttons are activated. Once these two
buttons have been activated, the message disappears and the Start/Stop and Move Steps buttons
will be available.
(d) If the WAKE or ENABLE buttons are selected during motor operation, the motor is immediately
stopped and the STEP control signal from the microcontroller is reset.
8. The DRV8846 EVM is now awake and can be commanded to turn the motor. This can be done by
either selecting the
Start/Stop Steps
,
Move # of Steps
, or
Reciprocate
buttons.
The
Start/Stop Steps
button is used to run the motor indefinitely. The motor will accelerate to the target
speed and run until the
Start/Stop Steps
button is selected. When the
Start/Stop Steps
button is
selected, the red button will change to green, and the
Move Steps
and
Reciprocate
buttons will be
disabled.
The
Move Steps
button is used to allow movement of an exact number of steps. When the
Move Steps
button is selected, the red button to the left of
Move Steps
will turn green, and the
Start/Stop Steps
and
Reciprocate
buttons are disabled until the number of steps have completed.
The
Reciprocate
button is a special case of the
Move Steps
. When selected, the motor will advance
the specified number of steps in the direction initially set by the control inputs. After a short pause, the
motor will then advance the same number of steps in the opposite direction. This sequence is repeated
until the
Reciprocate
button is selected.
When the
Reciprocate
button is selected, the red button to the left of
Reciprocate
will turn green, and
the
Start/Stop Steps
and
Move # of Steps
buttons are disabled until the number of steps have
completed.
5
SLLU203A – June 2014 – Revised March 2015
DRV8846 Evaluation Module
Copyright © 2014–2015, Texas Instruments Incorporated
