After having some trouble with scanf & printf (scanf receives 0x0D and convertes this to 0x0A) (printf attaches CR to \n)
i ask myself: where's the Sourcecode of all this function's? Printf & scanf sin, cos and all this stuff are library-functions. Can they be changed, it is useful to change them? Can i learn something for example how sin is computed?
Of course i've learned from this: now i use my own my_putchar & my_getkey when transmitting/receiving singele binary char's.
"In the keil/lib folder there are some source files."
True - but not printf nor scanf.
The provided files are documented in the Manual:
http://www.keil.com/support/man/docs/ca/ca_lib_source.htm
These are the only ones that should need customisation!
If you really want some source, take a look at an Open-Source compiler like GCC...
"These are not parts of the C language standard, just extensions."
No, that's not quite true. Although not actually part of the language, the requirements of the standard library - including printf and scanf - are part of the standard!