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

PCD option to assign variables to near/far data space?

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



Joined: 27 Aug 2008
Posts: 2337
Location: Germany

View user's profile Send private message

PCD option to assign variables to near/far data space?
PostPosted: Sun Nov 02, 2008 1:52 pm     Reply with quote

Hello,

dsPIC30/PIC24 processors have its data space divided to a near (up to 0x1FFF) and a far (above 0x2000) data space. Cause the near data space has additional addressing modes, it's particularly effective for direct variable addressing, while buffers and structures, that are mainly accessed through pointers can reside in far data space as well.

PCD apparently assigns the variables sequentially during compilation without considering access requirements.

It's possible now, to use a #locate to absolute addresses to force e. g. the placement of large buffers or structures in far data space, but it would be more convenient, to have a special pre-processor directive (like #near #far) for this purpose. Or did I miss another already existing option?

Best regards,
Frank

P.S.: I learned, that the questioned option is available through addressmode () statement and user defined storage qualifier or #type default= preprocessor directive.
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