Hello Community:

I am very new to linux at all levels, I've managed to configure buildroot, cross-compiling linux for ARM sam SoCs even I have mounted and ran both uImage/zImage jffs2/ubifs on my target.

But, I have several problems:

1. TFT LCD Display 4,3" NHD-4.3-480272EF-ATXL#-T: I have to change from the LCD coming in the sam9x35ek to this one. I have the hardware done, because with an already programmed SoC the system works. But now i have to program my linux config for this display and I tried several Combinations nothing works. enabled TFT Smal lcd support on kernel configs, this display has backlight white with pwn intensity control. i see ALL FULL white. and also i dont see the bootstrap image before entering kernel, that has microchip logo (this is seen in the Eval kit lcd)
2. Implementation for My app: I dont know where to start for making my own app, I dont understand how this is done. AS an example: I have received an application that uses Netbeans projects as libraries.so (you compile your code into *.so) and then these are managed by "custom services" that run on /usr and are launched at init with scripts named S85, S86 and so on. How is this way of making an app called? i just need to be pointed in the right direction.
3. Tools for creating App: is there another way of creating apps for embedded linux? easier? I just need and app that runs alone full screen, this app would manage hardware through kernel. May be, could start with something easy.
4. dirctories For my app: where and how to put my app files? how to run it with scripts?

I dont want you to asnwer all the above questions in detail i rather prefer directions on the different topics. Mostly about making an app on linux for an embedded system i just dont get it. Is the same for a desktop app? on Ubuntu for example? can i start from there and then go to embedded?

Thank you very much!

First, you need the tool chain for the target processor: compiler, linker, debugger, assembler. After you get that, come back here and tell me.

I Guess i mentioned that:the SoC is an Atmel sam9x35 compiled with buildroot, and the Cross compile toolchain is Made on buildroot. Compiler gnu GCC, uclib in kernel and i pretende using eclipse.
Besides your answer is very rude and you seem to havent learnt todo read. I AM very new yo Linux embedded

Kind of a lot going on with your question. (don't feel the answer was rude either)

There are so many ways to create a program. What you mentioned was netbeans. It is rather complete build environment. Only a few like that exist free I'd think. Many other limited build environments exist. Then you get to making code one line at a time. It may be possible to take existing code and form it to your own.

Part of your request keeps asking about embedded. Generally you have to create minimal programs using minimal everything.

So, where to start?? I'd say keep looking at online examples and code snippets for examples.

Might be worth it to get involved in C programming in that search. Be sure to build some hello world examples and test it. Then branch out.

Sorry, I guess my speed-reading class didn't really work. So, you've got the tool chain. It sounds like now you want to make hardware drivers. In Linux those programs are called kernel modules. If you look through the kernel sources, you can usually find something close to what you want, and then tweak it a bit.

Or, do you want to write application programs? Whatever you write, if it's for an embedded system, it should be small and light, because you're limited on ram memory and processor power.

I want to write Application, but before that i need to understand how this works in embedded, what i mean is that for example:
BuildRoot puts an overlay in the Root File System with USER apps in /usr folder, then by some script it auto runs on linux init sequence. I get this, but, how do i make these apps?
I believe that my problem is that i havent made an app for ANY linux, should i start making one for Ubuntu in my desktop and then go for embedded?

Embedded means "not a general purpose computer". It means that the system's primary function is not to be a desktop system where you can do all typical desktop functions. A museum learning display could be called an embedded computer. The smart display on an appliance could be called an embedded computer. Other examples might be a home router, a car computer, a cash register, a handheld scanner that a shipping company like FedEx or UPS uses, a pacemaker, a heart monitor. Some of them have displays, some of them do not.

An app or application is just a program written to do a certain thing.

A great starting point is to select a programming language and learn how to create programs using it. C is an excellent example.

There are a great many projects for small modules available to play with as examples, BeagleBoard, Hummingboard, Gumstix, and Raspberry Pi are a few of them, with the Pi being one of the most prolific. Suggest you pick up a version of the Pi as well as some of the example projects and hardware, such as accelerometers and real time clock peripherals. Most of those have example programs where you can learn and then take some next steps.

This topic is not a small project. I know you didn't represent any opinion to this effect. My point here is that the topic of embedded programming is very large and encompassing. While one can experience a great amount of it in a brief time with some sample kits, the very broad scope of the topic area is much larger. Therefore these are some starting suggestions and the best course of action would be to experiment independently with things to try to learn. Every embedded programmer is a "tinkerer" who likes to take things apart, learn how they work, and many times looks to provide solutions for things where you didn't think computation was a solution at all.

Speaking from over 30 years of embedded experience, my desk is a lab.

1 members found this post helpful.

Wow, well this is scary, but I have to learn this because its my work and i was assigned to it. I have at my disposal the sam9x35ek but there is no many examples available of final apps.
So I will start for PI, which i'm considering buying but for my home and do stuff for myself, so i guess it will be two times as worth.
Thank you.