This is a simple tethered application where you type in left and right wheel speeds, and run time in milliseconds, into a terminal.  When you press Enter, your text gets parsed and executed by the micro:bit, which then makes the cyber:bot execute the maneuver.

Hardware Setup

• Set the cyber:bot board's power (PWR) switch to Position 0.
• Make sure the battery holder is loaded with 5 AA batteries.
• Make sure the battery holder's barrel plug is firmly plugged into the cyber:bot board's barrel jack. 
• Connect the cyber:bot to your computer with a USB cable.

Software Setup

• In a Google Chrome or Microsoft Edge browser, go to python.microbit.org to open the micro:bit Python Editor.
• Make sure the cyberbot.py module is added to the Project Files.
  (See Add modules to your micro:bit).

Example Script: terminal_controlled_bot_tethered_intro

• Set the project's name to terminal_controlled_bot_tethered_intro, enter the script below, and then click Save.
  (See Save & Edit Scripts and Flash Scripts with Python Editor.)
• Click Send to micro:bit.  
  (See Flash Scripts with Python Editor.)
• Set the cyber:bot board's PWR switch to 2.

Example Script: terminal_controlled_bot_tethered_intro

# terminal_controlled_bot_tethered_intro

from cyberbot import *

sleep(1000)

print("\nSpeeds are -100 to 100\n")

while(True):
    text = input("Enter left speed: ")
    vL = int(text)

    text = input("Enter right speed: ")
    vR = int(text)

    text = input("Enter ms to run: ")
    ms = int(text)

    bot(18).servo_speed(vL)
    bot(19).servo_speed(-vR)
    sleep(ms)
    bot(18).servo_speed(None)
    bot(19).servo_speed(None)

    print()  

Since your cyber:bot is currently tethered, it’s best to use low speeds and short run times.  Otherwise, your cyber:bot might try to roll beyond the tether length.  In other words, it’ll try to unplug itself from the USB cable, or maybe roll off the table.

• Click Show serial to open the serial monitor.
  (See Use the Serial Monitor.)
• Click in the serial monitor and type 25 in response to the Enter right speed: prompt, then press Enter.
• Type 25 in response to the Enter left speed: prompt, then press Enter.
• Type 750 in response to the Enter ms to run: prompt, and press Enter.
• Verify that your cyber:bot rolled forward for about ¾ of a second.
• Next, try -25, -25, and 750.  Did it roll backwards?
• Now, try 25, -25, 750.  Did it pivot to the right?
• Try 25, 10, 750 for a curving motion.
• Can you make it turn in place left and right?
• Try causing an exception by typing non-digits in response to one of the prompts. 

For example, what happens if you type abc and press enter?  For now, you can press/release the reset button to restart the app.  You will add some exception handling in the your turn section to prevent this from happening.

Setting PWR switch to 0 vs. Unplugging Battery Holder   

Taking a break, building a circuit, or writing a script?    

• Just set the cyber:bot board's PWR switch to 0 until it's time to test the next script.

If you are done for the day, always follow these steps.

• Set PWR to 0.
• Unplug the battery holder's barrel plug from the cyber:bot board's barrel jack.