Assign register value to variable

[artvolk]

Posted on June 06, 2011 at 21:05

Good day!

I'm trying to assign register value to a variable in COSMIC C. I've tried the obvious way first, but it doesn't work:

uint8_t test = 0;

...

test = CLK->SWCR; // define from stm8s.h

and

uint8_t test = 0;

...

test = CLK_SWCR; // define from ''C:\Program Files\COSMIC\CXSTM8_32K\Hstm8\iostm8s.h''

When I run my program in Debug mode and create a watch for 'test' variable it is always zero.

What can be wrong?

Thanks in advance!

[luca239955_stm1_st]

Posted on June 07, 2011 at 08:31

Hi,

one possibility is that your variable ''test'' is optimized away: declare it volatile as a minimum.

Also check that the hardware register you are reading does not actually contain zero.

Hope it helps.

Luca

[artvolk]

Posted on June 07, 2011 at 22:54

Thank you a lot, it seems it was really optimized, despite it was builded in Debug mode.

'volatile' does the trick, thanks a lot!