Stop immediately at the black line.

[MSN-00100]

Dir sir.

We useing the pybricks ver.4.0 for PrimeHub.
I have a quition.

I making a program to move straight until a black line is detected.
I want it to stop immediately upon detecting the black line.
I programmed it as shown below, but it continues to coast,
so it cannot stop immediately.

This is part of the program.

MOTOR_L = Motor(Port.A, Direction.COUNTERCLOCKWISE)
MOTOR_R = Motor(Port.E, Direction.CLOCKWISE)
COLOR_LINE = ColorSensor(Port.B)
DB = DriveBase(MOTOR_L, MOTOR_R, 62.4, 158)
DB.use_gyro(True)
DB.reset()

DB.settings(straight_speed=(400, straight_acceleration=(350, 700))
DB.drive(400, 0)

while not(await COLOR_LINE.reflection() > 20):
    pass

DB.break()

Please tell me how to solve the problem.
Thank you.

[dlech]

Did you try DB.hold() instead of DB.brake()?

[MSN-00100]

Thanks for the reply.
I tried both DB.hold() and DB.break(), but it doesn't stop immediately.

[laurensvalk]

When the program ends, the motors coast.

So to see the effect of brake or hold at the very end, just put in a wait at the end.

[MSN-00100]

Thanks for the reply.
I was able to make it stop by using await DB.straight(3, Stop.BRAKE) instead of DB.break(). Is this okay?