Output and Pauses
Outputs
On the front of the micro:bit is an 5 by 5 array of LEDs (Light Emitting Diodes). Along with the speaker, the LEDs are the only outputs* on the micro:bit and can be used to display text, numbers and images.
The LEDs can be turned on and off in a number of different ways.
Ordinarily each of the outputs will stay on unless another instruction is given to the LEDs.
To turn them off we use the Clear Screen block. This is a basic command, but found under the 'More' menu.
Examples
Press the A button on the micro:bits below to see an example of each output type.
Show String displays a scrolling message
Show Icon displays a preset image or 400ms
Show leds shows a custom designed image for 400ms
Show Number displays a number for 750ms
Pauses
If we want the output to stay on longer than the built in display time, we will need to add a pause before we turn them off.
Pauses are measured in milliseconds (ms).
Example
To make an image stay on the screen for 2 seconds (2000ms) then we need to add a pause of 1600ms (because 'Show Image' already shows the image for 400ms).
Challenge
Create a program that when you press the A button has a 3 second countdown, then shows a smiley face for 5 seconds.
Key Words
Output
Computer generated information that a computer can display on screen, print on paper or produce through speakers. Other output could be movement (turning motors off and on).