Welcome to Tiny:bit Robot Car repository

Learning goal：

This lesson learns how to control car speed by Python programming.

Code_1:

Code_2:

1) Import the library needed for this lesson from microbit: display for dot matrix display, Image calls the built-in image, tinybit controls the car;

2) display.show(Image.HAPPY)：Display A smile on the micro:bit dot matrix.

3) Method1:

tinybit.car_run(a,b)：Set the speed of car. The first parameter a indicates the speed of the left motor (0 ~ 255), and the second parameter b indicates the speed of the right motor (0 ~ 255).

4) Method2:

tinybit.setMotorPWM(a,b,c)：This function adjusts the speed of the motor.

The parameter a controls the left motor, the value range is -255 ~ 255, a positive number indicates the left motor rotates forward, a negative number indicates the left motor reverses,0 indicates stop.

The parameter b controls the right motor, the value range is -255 ~ 255, a positive number is right motor rotates forward, a negative number is right motor reverses, 0 indicates stop. 

The parameter c is delay time, unit is millisecond (ms).

From the hardware interface manual, we can know that the tracking sensor is directly driven by the micro:bit IIC pin.

Position of motor as shown below:

Programming and downloading：

1.You should open the Mu software, and enter the code in the edit window, , as shown below.

Note! All English and symbols should be entered in English, and the last line must be a space.

2.You can click the “Check” button to check if our code has an error. If a line appears with a cursor or an underscore, the program indicating this line is wrong.

3.Click “REPL” button,check whether the tinybit library has been downloaded. If not, please refer to the [preparation before class]---> [Python programming]

4.Click the “Flash” button to download the program to micro:bit board.

If the program is wrong or the experimental phenomenon is wrong after downloading, please confirm whether you have downloaded the Buildingbit libraryhex file we provided to the micro: bit board.

For the specific method of adding library files, please refer to 【1.Preparation before class】---【Python programming】

Experimental phenomena:

After download is complete, open the power switch. The micro:bit dot matrix will display a smile, and the speed of the two motors will gradually increase, increasing the speed every second, running for one second after reaching the highest speed, and stopping for one second. And keep looping like this status.