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11. Input devices

This is the documentation of week 10 activity Input devices by Ahmad Tijjani Ishaq and Muhammad Jidda.

As for our individual Assignment it can be found here Jidda and Ahmed

Group tasks

The group task for this weeks activity is to probe an input device’s analog levels and digital signals.

Input Devices

Input devices are often refer to as sensors. Sensors play a critical role in embedded systems by detecting and measuring physical phenomena, converting them into electrical signals that can be processed by the microcontroller.

Examples of input devices are: - joystick/Potentiometer - PIR sensor - keypad/button - Proximity sensor - microphone etc

we tasted the analog/digital levels of the following: - Joystic Module - Mic module

Equipments

We used the following testing equipments: - Oscilloscope - DC Power supply

Oscilloscope

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An oscilloscope is a vital electronic instrument used for visualizing and analyzing the waveform of electronic signals. It displays a graph of voltage signals over time, allowing users to observe the behavior of electrical signals in real-time.

DC Supply

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A DC (Direct Current) power supply is an electrical device that converts alternating current (AC) from a mains power source into a steady, continuous flow of direct current. DC power supplies are used in various applications across industries such as electronics, telecommunications, automotive, and manufacturing.

Joystick Module

A joystick module is a versatile input device commonly used in electronic projects and gaming peripherals. Resembling a miniature control stick, it typically consists of a movable stick mechanism mounted on a base, along with potentiometers that detect its position in multiple axes, such as up/down and left/right movements. These modules often feature tactile feedback, allowing users to feel subtle changes in direction and resistance as they manipulate the joystick. With its intuitive interface, the joystick module offers precise control over various applications, from controlling robotic arms to navigating virtual environments in video games. Its compact size and ease of integration make it a popular choice among hobbyists and professionals alike for adding interactive functionality to their projects.

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connection we measured the signal from one of the potentiometer(y) on the joystick module using the oscilloscope.

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we powered the module using the DC supply at 5v by connecting the +ve probe to the 5v pin and -ve probe to the GND pin of the joystick.

Then we connect the black probe of the oscilloscope to the GND of joystic module and the red probe to the VRy pin of the joystick module.

result

when we move the joystick along the y axis(since we connected to it) we get a corresponding movment on the oscilloscope as shown below.

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Microphone Module

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The microphone module is a breakout board that contains an electret microphone and a pre-amp. The module is used to pick sound waves and give out corresponding analog and digital signals.

For our activity we test both the two outputs from the module. for more on how to use the module here is a great Reference

connection

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we power the module using the DC supply at 5v by connecting the -ve probe of our supply to GND of module and +ve probe to VCC of module.

We then connected the red wire (+ve probe) of our oscilloscope to the analog AO (analog out) pin of our module and connected the Grounds.

when we play music from our phone we get the following output at the oscilloscope.

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We repeated similar steps but changed the connection from Ao to Do pin of the module and we measured the digital output and its shown below.

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with that we come to the end of our documentation.


Last update: April 16, 2024