# LED显示屏

BBC micro:bit上的LED显示屏包含了25颗红色的LED灯。这些灯呈5x5的网格状排列（横排5颗LED灯，竖排5颗LED灯）。

# 哪个LED ？

`0, 0` `1, 0` `2, 0` `3, 0` `4, 0`

`0, 1` `1, 1` `2, 1` `3, 1` `4, 1`

`0, 2` `1, 2` `2, 2` `3, 2` `4, 2`

`0, 3` `1, 3` `2, 3` `3, 3` `4, 3`

`0, 4` `1, 4` `2, 4` `3, 4` `4, 4`

The x, y coordinates for the LED in the centre of the grid are `2, 2`. Starting from `0, 0` count over 2 columns and then down 2 rows.

### 行，列 -1

Since the row and column numbers start at 0, an easy way to figure out the x, y coordinates is to subtract 1 from the row and column number (when counting from 1). In other words, to specify the LED in the 4th column 5th row, subtract 1 from each number to get coordinates `3, 4`.

# LED编程

## MakeCode编辑器

### LED 打开/关闭

Use + 绘制 and 不绘制 to turn an LED on or off.

### 一个 LED 是打开还是关闭？

Use the point function to find out if a LED is on or off.

### 显示图像、 字符串和数字

Instead of turning individual LEDs on or off, as above, you can display an image directly to the screen or show text/numbers on screen using the show number/show string function.

## Python

See the images section of the documentation to learn more about programming the LEDs in Python for micro:bit.