6. Show text

6.1. display.show simple version

display.show(value)
Display letters/digits of a string, float or integer, in sequence.
Each letter, character or digit is shown with 400 milliseconds between them.

To show the string, ‘Hi’, one character at a time on the display, use display.show('Hi'):

from microbit import *

while True:
    display.show('Hi')

To show the integer, 16, one digit at a time on the display, use display.show(16):

from microbit import *

while True:
    display.show(16)

To show the float, 3.14, one digit at a time on the display, use display.show(3.14):

from microbit import *

while True:
    display.show(3.14)

Tasks

  1. Write code to show your school house color.

  2. Write code to show your height in cm.

  3. Write code to show the chances of getting a 6 on a die throw.

Write code to show your school house color.

from microbit import *

while True:
    display.show("Hughes")

Write code to show your height in cm.

from microbit import *

while True:
    display.show(182)

Write code to show the chances of getting a 6 on a die throw.

from microbit import *

while True:
    display.show(0.16)

6.2. Display.clear

display.clear()
Clear the display.
After display.show is used, the last digit or character will be left displayed.
Use display.clear() to remove the last digit or character from the display.
Use a sleep after the clear so that the display remains blank for a short time.
from microbit import *

while True:
    display.show(3.14)
    display.clear()
    sleep(2000)

Tasks

  1. Write code to show 123, then clear the screen for 1 sec.

  2. Write code to show “ABC”, then clear the screen for half a sec.

Write code to show 123, then clear the screen for 1 sec.

from microbit import *

while True:
    display.show(123)
    display.clear()
    sleep(1000)

Write code to show “ABC”, then clear the screen for half a sec.

from microbit import *

while True:
    display.show("ABC")
    display.clear()
    sleep(500)

6.3. display.show with clear

display.show(value, clear=False)
Display letters/digits of a string, float, in sequence.
If clear is True, the display will be cleared after it has finished. Its default value is False, in which case, the last character is left displayed.
After display.show is used, the last digit or character will be left displayed.
Use clear=True to remove the last digit or character from the display.
Use a sleep afterwards so that the display remains blank for a short time.
e.g. display.show('Hi', clear=True)
from microbit import *

while True:
    display.show(3.14, clear=True)
    sleep(500)

Tasks

  1. Write code to show 123, with the last character being removed, then sleep for 1 sec.

  2. Write code to show “ABC”, with the last character being removed, then sleep for half a sec.

Write code to show 123, with the last character being removed, then sleep for 1 sec.

from microbit import *

while True:
    display.show(123, clear=True)
    sleep(1000)

Write code to show “ABC”, with the last character being removed, then sleep for half a sec.

from microbit import *

while True:
    display.show("ABC", clear=True)
    sleep(500)

6.4. display.show with delay

display.show(value, delay=400)
Display letters, characters, and digits of a string, float or integer, in sequence.
Each letter, character or digit is shown with delay milliseconds between them.
The default delay is 400ms. When no delay is specified the default of 400ms is used.
The delay can be specified with the parameter name as in display.show('Hi', delay=400), or just as a number as in display.show('Hi', 400).

To show the string, ‘Hi’, with a short delay of 200ms, use display.show('Hi', 200):

from microbit import *

while True:
    display.show('Hi', 200)
    display.clear()
    sleep(2000)

To show the float, 3.14159, across the display slowly use a medium delay of 300ms via display.show(3.14159, delay=300):

from microbit import *

while True:
    display.show(3.14159, delay=300)
    display.clear()
    sleep(2000)

Tasks

  1. Write code, using a short delay of 200ms, to show 99.94, then clear the screen for 1 sec.

  2. Write code, using a short delay of 150ms, to show 5.64, then clear the screen for half a sec.

Write code, using a short delay of 200ms, to show 99.94, then clear the screen for 1 sec.

from microbit import *

while True:
    display.show(99.94, delay=200)
    display.clear()
    sleep(1000)

Write code, using a short delay of 150ms, to show 5.64, then clear the screen for half a sec.

from microbit import *

while True:
    display.show(5.64, delay=150)
    display.clear()
    sleep(500)

6.5. Show at different speeds

The code below uses a shorter delay for the initial text then a longer delay for the main information.
from microbit import *

while True:
    display.show('I like the ', delay=200)
    display.show('NBA', delay=400)
    display.clear()
    sleep(2000)

Tasks

  1. Modify the code below to display your favourite activity.

from microbit import *

while True:
    display.show('I like to', delay=200)
    display.show('ride my bike', delay=400)
    display.clear()
    sleep(2000)

  1. Modify the code below to display your name and age in years.

from microbit import *

while True:
    display.show('My name is', 200)
    display.show('?????', 400)
    display.show('I am', 200)
    display.show('??', 400)
    display.clear()
    sleep(2000)

6.6. display.show using variables

In the code below, 3 variables are used to hold a string, integer and float.
These variables are then showed repeatedly in the while True: loop.
This makes it easy to see and edit the values of the variables being used in the code.
from microbit import *

player = 'Dunstall'
goals = 1254
goals_per_game = 4.66

while True:
    display.show('Player', 200)
    display.show(player, 400)
    display.show('Goals', 200)
    display.show(goals, 500)
    display.show('Goals per game', 200)
    display.show(goals_per_game, 600)
    display.clear()
    sleep(2000)

Tasks

  1. Modify the value of the variables below to display info for another great goal kicker.

    from microbit import *

player = 'Romario'
goals = 780
goals_per_game = 0.78

while True:
    display.show('Player=', 200)
    display.show(player, 300)
    display.show('Goals=', 200)
    display.show(goals, 400)
    display.show('Goals per game=', 200)
    display.show(goals_per_game, 500)
    display.clear()
    sleep(2000)

  2. Modify the code below to display info for another great bowler.

    from microbit import *

bowler = 'Muralitharan'
wickets = 800
ave = 22.7

while True:
    display.show('Bowler=', 200)
    display.show(bowler, 300)
    display.show('Wickets=', 200)
    display.show(wickets, 400)
    display.show('Ave=', 200)
    display.show(ave, 500)
    display.clear()
    sleep(2000)

  3. Modify the code below to display info for another prolific NBA scorer.

    from microbit import *

player = 'Kareem Abdul-Jabbar'
points = 38387
ave = 24.6

while True:
    display.show('player=', 200)
    display.show(player, 300)
    display.show('Points=', 200)
    display.show(points, 400)
    display.show('Ave=', 200)
    display.show(ave, 500)

6.7. Show full syntax

display.show(value, delay=400, \*, wait=True, loop=False, clear=False)
Display letters/digits of a string, float, in sequence.
Each letter, digit or image is shown with delay milliseconds between them.
The default delay is 400ms. When no delay is specified the default of 400ms is used.

The use of \*, in the syntax is to indicate that for those parameters after it, wait, loop and clear, the arguments must be specified using their keyword.

If wait is True, this function will block until the animation is finished, otherwise the animation will happen in the background.

If loop is True, the animation will repeat forever.

If clear is True, the display will be cleared after it has finished.

Tasks

  1. Experiment with the show named parameters by trying them out with True or False to see what effect they have.

Tip

display.show has a wait parameter that can be set to False so that displaying information on the microbit display doesn’t hold up other actions like driving motors on a bot.
e.g. display.show(motor_speed, wait=False)