three projects down

docs/projects/smiley-buttons.md

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+![](/static/mb/projects/a2-buttons.png)
+
+Use buttons to show a smiley or frowny face. 
+
+## Step 1
+
+Use [show leds](/reference/basic/showLeds) to make a smiley face:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+```
+
+## Step 2
+
+Add an input block for when [button A is pressed](/reference/input/button-is-pressed), and put a
+frowny face inside it:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+input.onButtonPressed(Button.A, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    . # # # .
+    # . . . #`);
+});
+```
+
+## Step 3
+
+Now add blocks so that when [button B is pressed](/reference/input/button-is-pressed), a smiley appears:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+input.onButtonPressed(Button.A, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    . # # # .
+    # . . . #`);
+});
+input.onButtonPressed(Button.B, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    # . . . #
+    . # # # .`);
+});
+```