Fixed DMA time comparison.

Change-Id: I9aa454f3a3c75bd2ad65c0bcb62591e1acbc17f8
diff --git a/frc971/wpilib/dma_edge_counting.cc b/frc971/wpilib/dma_edge_counting.cc
index 102d12b..7f87956 100644
--- a/frc971/wpilib/dma_edge_counting.cc
+++ b/frc971/wpilib/dma_edge_counting.cc
@@ -38,7 +38,7 @@
         }
 
         if (remaining == 0) {
-          if (sample_time_ < current_sample.GetTimestamp()) {
+          if (sample_time_ < current_sample.GetTime()) {
             // If the latest DMA sample happened after we started polling, then
             // just use the values from it because they're more recent.
             for (auto &c : handlers_) {
diff --git a/frc971/wpilib/dma_edge_counting.h b/frc971/wpilib/dma_edge_counting.h
index c145268..9347c83 100644
--- a/frc971/wpilib/dma_edge_counting.h
+++ b/frc971/wpilib/dma_edge_counting.h
@@ -165,7 +165,7 @@
   ::std::vector<DMASampleHandlerInterface *> handlers_;
 
   // The time at which we most recently read the sensor values.
-  double sample_time_ = 0.0;
+  uint32_t sample_time_ = 0.0;
 
   DISALLOW_COPY_AND_ASSIGN(DMASynchronizer);
 };