Update pinMode.adoc

Fixed code syntax typo

Author: animeshsrivastava24

Language/Functions/Digital IO/pinMode.adoc

@@ -19,7 +19,7 @@ subCategories: [ "Digital I/O" ]
 === Description
 Configures the specified pin to behave either as an input or an output. See the http://arduino.cc/en/Tutorial/DigitalPins[Digital Pins] page for details on the functionality of the pins.
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-As of Arduino 1.0.1, it is possible to enable the internal pullup resistors with the mode INPUT_PULLUP. Additionally, the INPUT mode explicitly disables the internal pullups.
+As of Arduino 1.0.1, it is possible to enable the internal pullup resistors with the mode `INPUT_PULLUP`. Additionally, the `INPUT` mode explicitly disables the internal pullups.
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