DMA: internal CPU cycles may execute during CPU<->DMA bus transition …

…cycles (see #380)
nba-emu · Jan 21, 2025 · 4945d05 · 4945d05
1 parent 61b0c90
commit 4945d05
Showing 1 changed file with 3 additions and 5 deletions.
diff --git a/src/nba/src/hw/dma/dma.cpp b/src/nba/src/hw/dma/dma.cpp
@@ -155,19 +155,17 @@ bool DMA::HasVideoTransferDMA() {
 }
 
 auto DMA::Run() -> int {
-  bus.Step(1);
-
   const auto timestamp0 = scheduler.GetTimestampNow();
 
+  bus.Step(1);
+
   do {
     RunChannel();
   } while(IsRunning());
 
-  const auto timestamp1 = scheduler.GetTimestampNow();
-
   bus.Step(1);
 
-  return (int)(timestamp1 - timestamp0);
+  return (int)(scheduler.GetTimestampNow() - timestamp0);
 }
 
 void DMA::RunChannel() {