From: mmaroti <mmaroti>
Date: Mon, 12 Apr 2010 09:21:20 +0000 (+0000)
Subject: change the time stamp calculation to never round up into the future
X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=commitdiff_plain;ds=sidebyside;h=42c536d3376434538d66d1b475b8a216e9abd086;p=tinyos-2.x.git

change the time stamp calculation to never round up into the future
(see the discussin with Steve McKown in tinyos-devel on 02/22/09)
Committed on the Free edition of March Hare Software CVSNT Server.
Upgrade to CVS Suite for more features and support:
http://march-hare.com/cvsnt/
---

diff --git a/tos/chips/cc2420/transmit/CC2420TransmitP.nc b/tos/chips/cc2420/transmit/CC2420TransmitP.nc
index 87898e2c..79250cf3 100644
--- a/tos/chips/cc2420/transmit/CC2420TransmitP.nc
+++ b/tos/chips/cc2420/transmit/CC2420TransmitP.nc
@@ -258,8 +258,10 @@ implementation {
   
   inline uint32_t getTime32(uint16_t time)
   {
-    uint32_t recent_time=call BackoffTimer.getNow();
-    return recent_time + (int16_t)(time - recent_time);
+    uint32_t recent_time = call BackoffTimer.getNow();
+
+    // time is always in the past
+    return recent_time - (uint16_t)(recent_time - time);
   }
 
   /**