Raptor PWM pin goes high on reboot (causes L298 motor to spin)

NETMF & Gadgeteer
1

Hi,

Not sure if anyone else has tried using a L298 board on the Raptor (or G400) yet?

When I hook up a L298 driver board and power it up, hit the reset button (even before I give it a program), the IN2 pin goes high and causes M1 motor to spin at full speed.

I can download a program.
Hit reset
Until the G400 is up and running, the motor spins.
The motor stops.
Then the G400 starts to process my code.

I assume it’s something in the firmware?

Any ideas on how to stop this? If not, my robot will try to kill me every time it powers up:)

2

You can tie it low by connecting with a 10k resistor to ground.

3

@ rbrainard - Looks like you hit upon a problem that also concerns me much. Put a capacitor of suitable size between the pwm pin and the pwm input for the motor. This will prevent any DC from getting to the motor controller.

4

The extender module is perfect for these things. Both suggestions are good but with the capacitor you must use pwm. I would use a resistor if not sure.