Now , I am using P1020RDB-PC.
The SDK provied a u-boot src, but I will use the P1020 with no OS.
So I need a simple boot to warm-up the board. Is there any example code or guide for writting the boot code?
anyone can help me?
You can build bareboard project in CodeWarrior (note that you will need V8.8 with correct updates to do that) as start point.
There are a lot of good reasons to use U-Boot.
Its primary purpose is to act as a boot loader for Linux, but it can be used *AS* your "operating system".
It has a working console port, command interpreter with shell and scripting, networking and file system support. It also sets up all your hardware so it is working. What more could you want 9assuming you don't want Linux or equivalent)?
You can add your "target application" as a U-Boot command. That allows you to boot up into a stable U-Boot and then run and test your Application from the shell. When it crashes you'll still be able to talk to U-Boot and use it to load the next version.
When you want to ship the product, all you have to do change the "Environment' (just like a Linux or DOS environment with saved shell variables and so on) to automatically run your application when it starts. You can even use the "environment" to store all sorts of configuration information for your product. More things you don't have to write yourself.
You might prefer to load your "application" over the network or off removable media and run it from U-Boot.
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