Changes between Version 5 and Version 6 of Old/Documentation/OTG/DebugNote

Timestamp:

Oct 26, 2005, 8:21:58 PM (19 years ago)

Author:

zhibinwu

Comment:

—

Old/Documentation/OTG/DebugNote

@@ -122 +122 @@
 }}}
 And the nodehandler will use the otg definition files (otg.rb) in this tmp/nodehandler/src/repository directory
+
+== Atheros Driver's Rate Control ==
+
+=== AutoRate (SampleRate) ===
+This is the default behavior:
+
+In ''ath_rate_findrate'' function of ath_rate/sample/sample.c
+
+{{{
+
+   if (sn->static_rate_ndx != -1) {
+                ndx = sn->static_rate_ndx;
+                *try0 = ATH_TXMAXTRY;
+        } else {
+                *try0 = mrr ? 2 : ATH_TXMAXTRY;
+   ...
+}}}
+Here , try0 means how many transmission attempts should be used for the first-rate-setting. 
+The above code means, if static rate is used, each packet will be retransmit ATH_TXMAXTRY-1 times.
+But if Mrr/SampleRate is used, the packet  will be tried in r0 rate only 2 times. if unsuccessful, r1, r2, r3,.. will be tried.
+in 3,3,0 times respecitively.
+
+The codes can be found in ''ath_rate_setupxtxdesc'' function of sample.c
+{{{
+... 
+    ath_hal_setupxtxdesc(sc->sc_ah, ds
+                             , rateCode, 3              /* series 1 */
+                             , sn->rates[0].rateCode, 3 /* series 2 */
+                             , 0, 0                     /* series 3 */
+                             );
+...
+}}}
+
+
+=== Static Rate ===
+
+In  ath/if_athvar.h
+{{{
+#define ATH_TXMAXTRY    11   
+}}}
+So, when it is set to fix rate, each packet will be transmit at this rate 11 times.