What is the famous and useful book for embedded c ?

Question by Blake: What is the famous and useful book for embedded c ?
Hi every one i am a software engineer currently working on J2ME
i have good grip in c,c++,j2EE and J2ME programming .i am very much interested to learn embedded c programming .Can any one suggest a best book for me on embedded c please if possible please send me the link for e-book even?

Best answer:

Answer by Luciano Clark
I have read Programming Embedded Systems: With C and GNU Development Tools, 2nd Edition, and found it useful. It’s a good place to start. If you already have a pretty good C understanding, and you know hardware rather well you should be able to get going with it pretty easily.

ISBN: 978-0596009830

You can look up the ISBN on Amazon or Half or anywhere, maybe even your local library.

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Question by sum142121: Why do we need oscillators and clocks in a microcontroller?
I am starting to learn embedded programming at work , and I am having trouble understanding a clock and oscillator.

Can you help ? What does an oscillator and a clock do ?

Best answer:

Answer by Grant d
The oscillators cycles on and off millions of times a seconds. This is the speed of the processor. Typically every 4 oscillator cycles is a clock cycle. The processor can do one instruction in a clock cycle, some take more that one clock cycle.

Oscillators and the clock control the speed of the processor.

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