8051 KEYPAD INTERFACE

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When we talk about input to the microcontroller unit, which may or may not be user input, it's not just ON/OFF switches or Push Buttons. In fact there are different methods for collecting data either from a user or the environment. According to the requirements, you can expect a user to press some button, toggle a switch, enter a username/password e.t.c. while various types of sensing devices are used to detect changes in the environment which will be discussed in my future posts. Today I am going to briefly introduce you to Keypad interface with the 8051 microcontroller. I have noticed many students having problem with this so I have tried my best to keep it as simple as possible while you will try your best to concentrate and understand it once and for all.


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