need help:newbie

I am new to this microcontroller;actually to microcontrollers in general.I am a student.I need help for my final yr project.How do I interface philips lpc2148 with my battery charger circuit?can anyone help me?

 Wrong time to start something completely new?

"I am new to ... microcontrollers in general"

Hmmm... isn't the point of a final year project supposed to be to demonstrate what you have learned on the course?
You should check with your supervisor that this is an appropriate choice of project.

By your final year, you should surely realise that "How do I interface [anything] with my battery charger circuit?" is unanswerable in the absence of any detail whatsoever about your battery charger circuit!

And, by your final year, you should be able to find and read the lpc2148 Datasheet and at least come up with some suggestion of a possible scheme...

It is, after all, supposed to be Your project!

 RE: Wrong time to start something completely new?

For some thing that simple, you are better of
using 8052 as opposed to ARM based processor.

Like the old saying "you have to learn how to walk
first before you can run"

 Jumping to conclusions?

"For some thing that simple"

How do you know the application is simple?

The only thing that's been mentioned is some unspecified sort of "interfacing" to some unspecified sort of "battery charger"

We have no idea what sort of interface it is (or needs to be), what sort of data is to be transferred via this "interface", what processing may be required, whether this forms a major part of the project or, indeed, anything much at all!

A bit early to declare that it's "simple", methinks?

 RE: Jumping to conclusions?

Well, there are a lot of battery charger chips made
by maxim (maxin-ic.com). Most of their chips have
a basic simple interface to CPU via SPI, I2C and
such. I don't see any compelling reason why you
would need an ARM processor for that. There are also
several apt notes available on the website that you
can download.

Now, If you are saying
that a 8052 CPU can't do it then you must be building
something very special !!

 RE: need help:newbie

the project description says arm controller and the supervisor had suggested the controller lpc2148.the battery charger should draw power from the usb.

i understand its "my" project sir but i am not very familiar with the microcontroller.I am struggling to understand the architechture and have been reading the datasheets for more than 3-4 weeks..with not much results.

we have only studied 8051 micrcontroller in our coursework.

 RE: need help:newbie

"the project description says arm controller"

That is not a project description - that is just the name of a component!

You need to start with a proper definition of your project Requirements - you cannot possibly solve a problem before you know what the problem is!

 Final Year Project

"the supervisor had suggested the controller lpc2148"

If he suggested it, then he must think that, by the final year of this course, you should be able to do it.

"I am struggling to understand the architechture and have been reading the datasheets for more than 3-4 weeks"

A final year project shouldn't be a walk in the park - you should expect a challenge!
If you are really struggling that much, then you need to discuss it urgently with your supervisor!

"we have only studied 8051 micrcontroller in our coursework."

So why not use one?
Part of your project report will need to discuss how you decided on the processor to use - "my supervisor told me" will probably not gain many marks...

 do it step by step

"the supervisor had suggested the controller lpc2148" [but] "we have only studied 8051 micrcontroller in our coursework"

seems like your supervisor is offering you bit of real world taste here. If you really want to get to the market and be a embedded developer, you will face new processors / system platforms quite often.

There is a daunting pile of datasheets to read about the ARM. You are probably not reading the right ones.

The chip datasheet will give you a description of each peripheral and detailed configuration information, but it assumes you are familiar with the ARM7 architecture. You should read the ARM ARM (architectural reference manual). Read at least chapters A1 and A2 (Introduction and Programmers Model) to get the grand picture on the ARM architecture, then proceed to reading the chip datasheet. That will give you the required hardware knowledge to make decisions like interfacing methods with your circuit.

All these manuals treat the processor at the lowest level. Unless your 'project description' requires you to write the firmware in assembly, you will use a C compiler. Both NXP and ARM have examples on how to do a lot of simple things and setup each peripheral in C, and you can program and simulate them in uVision.

Even with the very scant information you gave us, there are several issues on your project that you need to address. For example, the USB port has limits on Vdroop and on max. current that can be drawn. If you are allowed to use a charger IC, there are ready-to-use chargers that can be powered from the USB.

I suggest you to set up very small programs and test them in the simulator to get a feel of programming for the ARM. You can simulate almost all peripherals without any real hardware, so you can use this controlled framework to learn how the peripherals are configured. Restricting the scope of each step makes incremental implementation easier.