Using EMIF and can't find no-stm option

Pablo Cottens

Other Parts Discussed in Thread: RM48L952

Hello, I am using an external memory and, as I'm using a RM48L952 revision C microcontroller, I know that I must use the --no-stm option so that the memory will work accordingly due to a bug in the sillicon (I know this problem is resolved in revision D).

The problem is that I couldn't find the --no-stm option in the project options and after some research I found this link.

This indicates that the --no-stm option must be inserted manually, so I did. I went to project->properties->set additional flags and wrote --no-stm which didn't work (it stated thta it isn't a valid option)

over 10 years ago

0 Enrique Lizarraga over 10 years ago

TI__Expert 4580 points

Hello:

Did you tried it with an underscore? --no_stm

Regards,

Enrique

0 Pablo Cottens over 10 years ago in reply to Enrique Lizarraga

Genius 3020 points

Yes, and I got the exact same problem

0 Christian Herget over 10 years ago

TI__Expert 6985 points

Hi Pablo,

Which version of the compiler are you using?
The switch was introduced in version 5.1.3, I believe.

Best Regards,
Christian

0 Pablo Cottens over 10 years ago in reply to Christian Herget

Genius 3020 points

Yeah ... I'm using 5.1.1 ... so ... is there no way to do this without upgrading the compiler version?

0 Christian Herget over 10 years ago in reply to Pablo Cottens

TI__Expert 6985 points

No, the only other way is to wait for the rev D silicon, where this issue will be fixed.
On the other hand there is often no need of the no_stm option, as there are not so many cases where STM instructions are generated by the compiler. STM is usually used to put CPU registers on the stack, if your stack is in the embedded SRAM than this is no issue.
Functions like, memcpy and memset from the C std lib are using STM and there are rare cases where the compiler generates STM, e.g. 64 bit variables and sometimes for structs.
So you could check your asm files if ASM is used.
You should also ensure to configure the EMIF address region as device or strongly order type of memory to avoid the CPU core itself to generate burst accesses to that region. This was discussed in another thread.

Best Regards,
Christian

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Using EMIF and can't find no-stm option