pxt-calliope/docs/lessons/counter.md

49 lines
1.4 KiB
Markdown
Raw Normal View History

2016-03-26 00:47:20 +01:00
# counter lesson
2016-04-02 01:22:47 +02:00
Learn how to create a counter with with on button pressed.
2016-03-26 00:47:20 +01:00
## Topic
Variables
## Quick Links
2016-04-13 17:27:45 +02:00
* [activity](/lessons/counter/activity)
* [challenges](/lessons/counter/challenges)
* [quiz](/lessons/counter/quiz)
* [quiz answers](/lessons/counter/quiz-answers)
2016-03-26 00:47:20 +01:00
## Prior learning/place of lesson in scheme of work
Learn how to creating a **variable** to keep track of the current count. We will be learning how to create a counter app using a variable as well as simple commands, such as on button pressed, and show number.
## Documentation
2016-04-05 07:33:13 +02:00
```cards
2016-03-30 00:59:00 +02:00
input.compassHeading()
2016-04-05 07:33:13 +02:00
basic.forever(() => {})
2016-03-30 00:59:00 +02:00
let x = 0
2016-04-05 07:33:13 +02:00
if (true) {}
2016-03-30 00:59:00 +02:00
basic.showString("Hello!")
basic.showLeds(`
. . . . .
. . . . .
. . # . .
. . . . .
. . . . .
`)
```
2016-03-26 00:47:20 +01:00
2016-04-13 17:27:45 +02:00
* **variable**: [read more...](/reference/variables/var)
* **arithmetic operators**: [read more...](/reference/types/number)
* **on button pressed** : [read more...](/reference/input/on-button-pressed)
* **show number** : [read more...](/reference/basic/show-number)
2016-03-26 00:47:20 +01:00
2016-03-30 00:59:00 +02:00
## Objectives
2016-03-26 00:47:20 +01:00
2016-03-30 00:59:00 +02:00
* learn how to create a variable as a place where you can store data so that you can use it later in your code, accessible across all functions, and in nested code blocks
* learn how arithmetic operators operate on numbers and return a number
* learn how to run code when an input button is pressed
* learn how to show a number on the LED screen, one digit at a time (scrolling from left to right)
2016-03-26 00:47:20 +01:00