Hi, i am new to ucontroller programming. I wanted to make some password and 7-segment display projects using 4x4 matrix keyboard as input, in C. I just need some simple example links or sample code or part to understand how to decode the keypad inputs. Thanks in advance.
Ofcourse i tried, and have sample examples also. But feel little difficult to understand the coding. Thats wat asked here, because if any doubt i can clarify with thier codes easily. Tried in this forum also but got ASM code.
For that reason only i asked part of code. Because experts only can point the specific example for a particular thing to a begginner.
This site discusses both C and assembler implementations.
I still feel you have level up your Google skills. Do ask specific questions about things you have a problem understanding, instead of expecting full solutions to be sent to you.
www.8052.com/.../167585
But have you really done any serious googling? I get over 5000 hits for "4x4 Matrix keypad 8051" Are you really saying that none of those gives you any help at all?
Even if a site doesn't answer all your questions, it should help you think of better keywords to improve your search.
And don't forget Google's Advanced Search options to further improve your results: www.google.co.uk/advanced_search
Specifically for source code, try http://codesearch.google.com
Note that the techniques for dealing with keypads and 7-segment displays are pretty much independent of what particular processor you use - so any book or site covering such interfacing should be able to help you.
Have you looked at the book list here: http://www.keil.com/books
Thanks for your guidence. I searched, i too got 5000 hits, but few sites has huge code structure, and few has very small ones. I gone through the codes also, but cant get easily, since compilers also different. So i thought that i may be wasting time. Then only i came here for help directly for keil. Because its easy for someone to direct me to a nice ones. Then i can read it confidentialy.
In other words, what you don't need is any source code at all!
What you do need is a basic understanding of the principles - irrespective of any processor, programming, or compiler.
You may be better to start looking for books or sites on basic (digital) electronics...
I knew basic concepts of Digital as well as C programing. That only made me to complete handson on led blinking, 7-segment driving, LCD display driving etc. that too googling myself and some reference books.
Right now i am experimenting with keypad and RS232 serial communication with 89c51. Even again and again going through the code for keypad to understand, i feel difficult to catch every steps. Anyhow i am going through your code. Will try to catch the concept soon. If i have doubt, the only option is asking others experts. Thats wat created the thread in this topic.
just a bit of help
keys must be debounced
Erik
You can use the Keypad encoder IC such as DFL-KEY55A or DFL-Key55B, which can convert the key pressed to RS232. Click on www.dafulaielectronics.com
You can use the Keypad encoder IC