The mindsensors.com NxtMMX motor controller uses the tacho-motor class, so most of the information in the tahco-motor tutorial is applicable. However, it does not support all of the possible functions of the tacho-motor class.
The NxtMMX does not have a way to monitor the duty cycle of the motor, so reading
duty_cycle attribute will return
-EOPNOTSUPP. Additionally, you cannot
specify the duty cycle to use (see Speed Regulation below), so writing to
duty_cycle_sp will also return
-EOPNOTSUPP as well.
The NxtMMX creates a lego-sensor class device that can be used to monitor the battery voltage of the NxtMMX.
There are two settings that are not changeable using the tacho-motor class,
namely 0x86-Pass Count and 0x87-Tolerance. If you need to change these, you can
do so by writing to the
direct attribute of the lego-sensor class
Example - set Pass Count to 10:
$ echo -e -n "\x$(printf '%x' 10)" | dd bs=1 of=direct seek=0x86