Re: Startup code

"Jet Morgan" <jm@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:d9tsta$po7$1@xxxxxxxxxxxxxxxxxxxxxxx
>
> That is still startup code, even if written in C.

In my opinion, startup code is code executed from the reset of the CPU,
until the call to main().
So any function you call from main() to setup up further things, no matter
how low level and essential they are, is not called startup code.

> The compiler vendor will not typically know how the processor
> is connected to the other devices, such as memory bus widths,
> clock timings etc. That's why YOU (the designer) has to write it.

If need be, yes.

> There seems to be this perception that startup code is specifically
> assembler. It *could* be written that way but I've always
> written my startup code in a combination of C and assembler.

Again, all startup codes I have seen so far, were written in assembler.
Probably because at startup time, there is no environment set up yet to run
compiled C code at all. But this only holds true with "my" definition of
startup code, where the call to main() is not executed yet.

Meindert


.

Relevant Pages

  • Re: Startup code
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  • Re: Startup code
    ... >In my opinion, startup code is code executed from the reset of the CPU, ... >> The compiler vendor will not typically know how the processor ... >Again, all startup codes I have seen so far, were written in assembler. ... there is no environment set up yet to run ...
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