topic Re: how to define function at Absolute Addresses in kL05Z32? in CodeWarrior for MCU

how to define function at Absolute Addresses in kL05Z32?

wangbaode — Fri, 30 Aug 2013 03:14:51 GMT

Hi,

I want to place my function at absolute address in codewarrior10.3.

how to define function at Absolute Addresses in kL05Z32?

Re: how to define function at Absolute Addresses in kL05Z32?

ZhangJennie — Wed, 04 Sep 2013 13:35:38 GMT

we need first specify a memory area to hold your variables/constants in Linker file .ld.

Then, in source code, use __attribute__ to place the variables/constants into this memory area.

I have created an example project for your reference.

Please note that memory section "my_section" is added in section MEMROY (line 26).

And in the follow, add placement .mydata (line53 ~ line58).

In main.c, place a const my_const into this memory area (line 9 of main.c).

Re: how to define function at Absolute Addresses in kL05Z32?

kai_liu — Mon, 28 Oct 2013 08:27:18 GMT

Will compiler play smart and optimize the unused variables and functions in absolute addresses?

For example, I design a ROM API in a memory area. The function seems an orphan in API development, how to prevent the compiler ignore them when building?

IAR? GCC?

Re: how to define function at Absolute Addresses in kL05Z32?

ZhangJennie — Mon, 28 Oct 2013 08:30:59 GMT

I suggest you use KEEP command in ld file. you can search this command in help manual for more information about it.

Re: how to define function at Absolute Addresses in kL05Z32?

kai_liu — Mon, 28 Oct 2013 08:52:56 GMT

Hi, Jennie,

I found KEEP directive in IAR help. Thanks.

Allan

Re: how to define function at Absolute Addresses in kL05Z32?

ZhangJennie — Mon, 28 Oct 2013 09:40:56 GMT

you are welcome