Code Highlight markup and Link colouration fix constants.adoc (#657)

Co-Authored-By: per1234 <[email protected]>

Author: animeshsrivastava24

Language/Variables/Constants/constants.adoc

@@ -38,16 +38,16 @@ When reading or writing to a digital pin there are only two possible values a pi
 
 [float]
 === HIGH
-The meaning of `HIGH` (in reference to a pin) is somewhat different depending on whether a pin is set to an `INPUT` or `OUTPUT`. When a pin is configured as an `INPUT` with link:../../../functions/digital-io/pinmode[pinMode()], and read with link:../../../functions/digital-io/digitalread[digitalRead()], the Arduino (ATmega) will report `HIGH` if:
+The meaning of `HIGH` (in reference to a pin) is somewhat different depending on whether a pin is set to an `INPUT` or `OUTPUT`. When a pin is configured as an `INPUT` with `link:../../../functions/digital-io/pinmode[pinMode()]`, and read with `link:../../../functions/digital-io/digitalread[digitalRead()]`, the Arduino (ATmega) will report `HIGH` if:
 
   - a voltage greater than 3.0V is present at the pin (5V boards)
   - a voltage greater than 2.0V volts is present at the pin (3.3V boards)
 [%hardbreaks]
 
-A pin may also be configured as an INPUT with `pinMode()`, and subsequently made HIGH with link:../../../functions/digital-io/digitalwrite[digitalWrite()]. This will enable the internal 20K pullup resistors, which will _pull up_ the input pin to a `HIGH` reading unless it is pulled `LOW` by external circuitry. This can done alternatively by passing `INPUT_PULLUP` as argument to the `pinMode()` funtion, as explained in more detail in the section "Defining Digital Pins modes: INPUT, INPUT_PULLUP, and OUTPUT" further below.
+A pin may also be configured as an INPUT with link:../../../functions/digital-io/pinmode[`pinMode()`], and subsequently made HIGH with `link:../../../functions/digital-io/digitalwrite[digitalWrite()]`. This will enable the internal 20K pullup resistors, which will _pull up_ the input pin to a `HIGH` reading unless it is pulled `LOW` by external circuitry. This can done alternatively by passing `INPUT_PULLUP` as argument to the link:../../../functions/digital-io/pinmode[`pinMode()`] funtion, as explained in more detail in the section "Defining Digital Pins modes: INPUT, INPUT_PULLUP, and OUTPUT" further below.
 [%hardbreaks]
 
-When a pin is configured to OUTPUT with `pinMode()`, and set to `HIGH` with `digitalWrite()`, the pin is at:
+When a pin is configured to OUTPUT with link:../../../functions/digital-io/pinmode[`pinMode()`], and set to `HIGH` with link:../../../functions/digital-io/digitalwrite[`digitalWrite()`], the pin is at:
 
   - 5 volts (5V boards)
   - 3.3 volts (3.3V boards)
@@ -57,21 +57,21 @@ In this state it can source current, e.g. light an LED that is connected through
 
 [float]
 === LOW
-The meaning of `LOW` also has a different meaning depending on whether a pin is set to `INPUT` or `OUTPUT`. When a pin is configured as an `INPUT` with `pinMode()`, and read with `digitalRead()`, the Arduino (ATmega) will report LOW if:
+The meaning of `LOW` also has a different meaning depending on whether a pin is set to `INPUT` or `OUTPUT`. When a pin is configured as an `INPUT` with link:../../../functions/digital-io/pinmode[`pinMode()`], and read with link:../../../functions/digital-io/digitalread[`digitalRead()`], the Arduino (ATmega) will report LOW if:
 
   - a voltage less than 1.5V is present at the pin (5V boards)
   - a voltage less than 1.0V (Approx) is present at the pin (3.3V boards)
 
-When a pin is configured to `OUTPUT` with `pinMode()`, and set to `LOW` with `digitalWrite()`, the pin is at 0 volts (both 5V and 3.3V boards). In this state it can sink current, e.g. light an LED that is connected through a series resistor to +5 volts (or +3.3 volts).
+When a pin is configured to `OUTPUT` with link:../../../functions/digital-io/pinmode[`pinMode()`], and set to `LOW` with link:../../../functions/digital-io/digitalwrite[`digitalWrite()`], the pin is at 0 volts (both 5V and 3.3V boards). In this state it can sink current, e.g. light an LED that is connected through a series resistor to +5 volts (or +3.3 volts).
 [%hardbreaks]
 
 [float]
 == Defining Digital Pins modes: INPUT, INPUT_PULLUP, and OUTPUT
-Digital pins can be used as `INPUT`, `INPUT_PULLUP`, or `OUTPUT`. Changing a pin with `pinMode()` changes the electrical behavior of the pin.
+Digital pins can be used as `INPUT`, `INPUT_PULLUP`, or `OUTPUT`. Changing a pin with link:../../../functions/digital-io/pinmode[`pinMode()`] changes the electrical behavior of the pin.
 
 [float]
 === Pins Configured as INPUT
-Arduino (ATmega) pins configured as `INPUT` with `pinMode()` are said to be in a _high-impedance_ state. Pins configured as `INPUT` make extremely small demands on the circuit that they are sampling, equivalent to a series resistor of 100 Megohms in front of the pin. This makes them useful for reading a sensor.
+Arduino (ATmega) pins configured as `INPUT` with link:../../../functions/digital-io/pinmode[`pinMode()`] are said to be in a _high-impedance_ state. Pins configured as `INPUT` make extremely small demands on the circuit that they are sampling, equivalent to a series resistor of 100 Megohms in front of the pin. This makes them useful for reading a sensor.
 [%hardbreaks]
 
 If you have your pin configured as an `INPUT`, and are reading a switch, when the switch is in the open state the input pin will be "floating", resulting in unpredictable results. In order to assure a proper reading when the switch is open, a pull-up or pull-down resistor must be used. The purpose of this resistor is to pull the pin to a known state when the switch is open. A 10 K ohm resistor is usually chosen, as it is a low enough value to reliably prevent a floating input, and at the same time a high enough value to not not draw too much current when the switch is closed. See the http://arduino.cc/en/Tutorial/DigitalReadSerial[Digital Read Serial^] tutorial for more information.
@@ -85,7 +85,7 @@ If a pull-up resistor is used, the input pin will be `HIGH` when the switch is o
 
 [float]
 === Pins Configured as INPUT_PULLUP
-The ATmega microcontroller on the Arduino has internal pull-up resistors (resistors that connect to power internally) that you can access. If you prefer to use these instead of external pull-up resistors, you can use the `INPUT_PULLUP` argument in `pinMode()`.
+The ATmega microcontroller on the Arduino has internal pull-up resistors (resistors that connect to power internally) that you can access. If you prefer to use these instead of external pull-up resistors, you can use the `INPUT_PULLUP` argument in link:../../../functions/digital-io/pinmode[`pinMode()`].
 [%hardbreaks]
 
 See the http://arduino.cc/en/Tutorial/InputPullupSerial[Input Pullup Serial^] tutorial for an example of this in use.
@@ -96,7 +96,7 @@ Pins configured as inputs with either `INPUT` or `INPUT_PULLUP` can be damaged o
 
 [float]
 === Pins Configured as OUTPUT
-Pins configured as `OUTPUT` with `pinMode()` are said to be in a _low-impedance_ state. This means that they can provide a substantial amount of current to other circuits. ATmega pins can source (provide current) or sink (absorb current) up to 40 mA (milliamps) of current to other devices/circuits. This makes them useful for powering LEDs because LEDs typically use less than 40 mA. Loads greater than 40 mA (e.g. motors) will require a transistor or other interface circuitry.
+Pins configured as `OUTPUT` with link:../../../functions/digital-io/pinmode[`pinMode()`] are said to be in a _low-impedance_ state. This means that they can provide a substantial amount of current to other circuits. ATmega pins can source (provide current) or sink (absorb current) up to 40 mA (milliamps) of current to other devices/circuits. This makes them useful for powering LEDs because LEDs typically use less than 40 mA. Loads greater than 40 mA (e.g. motors) will require a transistor or other interface circuitry.
 [%hardbreaks]
 
 Pins configured as outputs can be damaged or destroyed if they are connected to either the ground or positive power rails.