CCS C Software and Maintenance Offers
FAQFAQ   FAQForum Help   FAQOfficial CCS Support   SearchSearch  RegisterRegister 

ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

CCS does not monitor this forum on a regular basis.

Please do not post bug reports on this forum. Send them to CCS Technical Support

Math routines

 
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion
View previous topic :: View next topic  
Author Message
Mortenc



Joined: 22 Feb 2007
Posts: 55

View user's profile Send private message

Math routines
PostPosted: Fri Feb 15, 2008 7:43 am     Reply with quote

Hello CCS forum.

I new with C programming (old assembler programmer)

I'm wondering.
If I make a division like:
(oscillator is 8 MHz)

signed int16 a;
signed int16 b;

a = b/2

this will take very long (about 200 uS) , but if I change the variables to unsigned it will take < 10uS.

All assembler programmer will probably use a RRF (rotate right file)
to make this and thats what CCS compiler do when we use unsigned variables. Why don't they do that with signed variables and just just controlling the sign after this. It must be much faster.
Am I wrong?
Display posts from previous:   
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group