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Rockbox mail archiveSubject: SH7034 and File APISH7034 and File API
From: Alan Korr <post_at_pegasmail.com>
Date: Thu, 28 Mar 2002 09:39:06 (GMT) >> Just a request : >> I prefer to be able to choose a byte or a word access thru >> on-chip addresses depending what I need to do. So avoid to >> defines this address with a fixed size access. > >I am a little curious, since I am new to this processor. When it is >interesting to select between byte and word accesses on a single on-chip >address? When I use 'clear_bit' or 'set-bit', I use a byte access because it is the only way to use atomic READ-MODIFY-WRITE operation on SH1. When I want to setup values for ports A and B, I prefer to use a 32-bit word access to setup both instead of two 16-bit words accesses for each (more compact and clever code). I chose to use gcc convention : - SI : single integer => 32-bit word - HI : half interger => 16-bit word - QI : quarter (?) integer => 8-bit word So when I want access one port as a byte, just do : value = QI(port_address); or QI(port_address) = value; Quite a simple and clear form, isn't it ? To be flexible enough is not a crime :). >>>Yes. Did anyone of you filesystem fiddlers (Linus, Alan, >> anyone?) think in terms of upper level api yet? I mean, not >> the specific details but in concepts? >> >> Too early. I prefer to do things in incremental order : > >I agree. First things first. Daniel, don't wait for us to have a file API if you need one. I first want to explore how to implement a clever way to handle file and folder with a maximal efficiency and a minimal waste space, before proposing a file API. So be free to have yours for the moment. _______________________________________________________________________ This mail was sent using http://www.pegasmail.com - Send Your Mail Now! Received on 2002-03-28 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |