Changeset 369 for OCO/trunk/drv16/waudio.cpp

Timestamp:

Sep 3, 2008, 4:08:49 PM (17 years ago)

Author:

rjerant

Message:

Fixed ticket:18 - streaming problem with video playback

File:

• OCO/trunk/drv16/waudio.cpp (modified) (2 diffs)

OCO/trunk/drv16/waudio.cpp

@@ -1287 +1287 @@
 #pragma on (unreferenced)
 {
+         ULONG  ulBytesPerIRQ; 
+         
 #ifdef DEBUG
     dprintf(("WAVEAUDIO::ConfigDev"));
@@ -1321 +1323 @@
     } /* endswitch */
 
-    // Calculate the PCMConsumeRate
+          // Calculate the BytesPerIRQ
+          // The BytesPerIRQ is the number of bytes consumed by this data format
+          // for every interrupt generated by the codec.
+          // This information is returned to the WAVESTREAM which uses it in
+          // buffer management decisions....
+          // rjj Fix for Bug #18 28082008
+         
+          ulBytesPerIRQ = pConfigInfo->ulSampleRate;
+          ulBytesPerIRQ >>= 5; // 32 interrupts per second
+                               // we can tweak this as needed but generally this should do rjj
+         
+          if (pConfigInfo->ulBitsPerSample == 16) {
+                ulBytesPerIRQ <<= 1;
+          }
+          if (pConfigInfo->ulNumChannels == 2) {
+                ulBytesPerIRQ <<= 1;
+          }
+          // make sure it's an even multiple of 64
+          ulBytesPerIRQ += 0x00000040;
+          ulBytesPerIRQ &= 0xFFFFFFC0;
+                
+          if (ulBytesPerIRQ > 0x800) {
+                ulBytesPerIRQ = 0x800;
+          }
+          pConfigInfo->ulBytesPerIRQ = ulBytesPerIRQ;
+
+          // Calculate the PCMConsumeRate
     // The consume rate is the number of bytes consumed by this data format
     // per second. It calculated by taking the following equation: